Thread Plug Gages

Any time that you are interested in getting the most out of your industrial equipment and supplies, you'll need to shop around and find the best maintenance tools. In this regard, a thread plug gage is one of the most important tools that you can invest in. When looking to get the most out of your industrial work, this tool will come in handy. In this regard, take advantage of the following tips so that you can learn about buying and using a thread plug gage for sale. #1: Look into the different types of thread plug gages for sale When you are setting out to buy this type of tool, it is critical to know what the market has in store. First of all, consider the equipment that you will be working on to see if there are any specific recommendations on the type of tool you should use. There are a number of different thread plug gages for sale, to include thread snap gages and ring gages. The more you understand about these different types of tools, the easier it will be for you to start shopping around with the best manufacturers. #2: Learn to use the tool to the best of your ability As you get more familiar with using thread plug gages, it becomes important that you continuously improve your skill and comfort level. Always take advantage of any training and continued education, so that you get the best performance possible. There are a lot of things you should know about getting the best thread plug gage performance, to include remaining aware of circumstances like pitch diameter, chip groove size, thread fit and sensitivity. You should also make sure that your workplace is as safe as it can be whenever using these tools. #3: Purchase the best possible models  Chances are high that you will find a brand that you feel most comfortable with. Shop around between the different models, until you choose the best tool for the job. Make sure that any tool you select has high wear resistance, ability to maneuver along different surfaces and that they are manufactured to current standards and certifications. By making sure you find the right thread plug gage for sale, you'll have a great chance to repair and maintain your equipment accordingly. Factor in these tips so that you can get what you need out of your industrial equipment tools and maintenance. For more information, contact companies like WESTport. 

A thread plug gauge is a very specific tool that allows you to make sure that various components fit together properly. In order for your thread plug gauge to provide you with accurate results, you need to make sure that you are using the thread plug gauge properly. Improper use could result in your thread plug gauge becoming damaged, and thus not providing you with the information you need. #1 Be Careful with Pressure The first thing you need to do is make sure that you are careful when applying pressure. There is no exact system for applying pressure to your thread plug gauge. However, when you apply a thread plug gauge, you should not have to apply force. It should easily fit into the threaded hole without you have to apply a lot of extra pressure. If you have to apply a lot of extra pressure, there is more than likely an issue with the threaded hole that you are trying to use the thread plug gauge on. If you can't get the thread plug gauge in without the use of excessive pressure, don't try to force it into place. #2 Only Have the Right Sized Gauge On Hand Second, make sure when testing threaded holes that you only have the exact sized thread plug gauge that you need on hand. Look up the size of the threaded hole that you are working with, and get out the thread plug gauge that is that exact size. Do not have other thread plug gauge outs. That way, you don't try to accidentally force the wrong sized thread plug gauge into a threaded hole, doing damage to the gauge and to the threaded hole at the same time. This is a simple trick to ensure that you don't make a mistake. #3 Work Slowly When testing multiple threaded holes, remember to work at a slow and steady pace. Do not rush when trying to get thread measurements. You are most likely to damage the thread plug gauge during the insertion and removal of the gauge into a threaded hole, especially if you are rushing and being rough. Instead, take your time with each measurement, carefully putting the thread plug gauge into each threaded hole and gathering the accurate measurements and data before taking the thread plug gauge out. Taking your time will ensure that you get accurate measurements without damaging your tools. The key to taking care of your thread plug gauge is to use it with care. Be careful and precise with how you use the tool in order to ensure that it lasts.

A BNC connector is an important addition to a coax cable because they let you hook up to the internet properly. However, an improper installation can be a major problem. As a result, it is important to take steps to fix this concern as soon as possible. Common BNC Connector Installation Mistakes Adding a BNC connector to a coax cable is a tricky situation that many amateurs don't do properly. As a result, they may suffer from a variety of problems that make it difficult to use them. Some of the most common mistakes including choosing the wrong connector size or choosing the incorrect bandwidth. These situations usually occur when somebody tries to install a BNC connector based on sight alone. When this happens, their connection is going to be very weak and may suffer from outages. These failures can be troubling to someone who needs high-quality internet connections at all times. As a result, it is important to take steps to address this problem. How A Thread Plug Gauge Can Help Thread plug gauges are designed to fit on the end of a threaded plug and to measure its size. They are very simple tools that anyone who works with these plugs should use on a regular basis. Using them with a BNC connector is a particularly wise decision. That's because they can allow you to hook up your connector to a coax cable without any mistakes. As a result, you can have high-quality internet that doesn't go out while you are using it. Fully understanding how to use one is a relatively-easy process that most people should be able to handle on their own.   Using A Thread Plug Gauge Using this tool is a very simple process. Start by looking at your BNC connector and taking an educated guess at its width. Then, carefully fit a gauge that looks close to that threaded plug over the BNC connector end. If you find that it fits snugly on the plug, you can use that diameter connector to install it to your system. However, if you find that the thread is too wide or tight, you can try another gauge to find the right diameter. Typically, this process should take no more than a few minutes to finish. However, it will give you an accurate fit that will ensure your BNC connector is tight and that your internet works smoothly and efficiently.   So if you plan on using BNC connectors any time in the future, it is wise to invest in a threaded plug gauge. These tools can also be used in other ways, which makes them a great item to have around the house for various installation needs.  Contact a company, like WESTport, for more help.

If your industry relies on incredibly precise measurements and components that are assembled with mathematical certainty, it's important that you invest in tools that will allow you to achieve those goals. Purchasing a reliable set of thread plug gages is a great way to constantly verify that your components will fit together as designed, but the tools themselves could be at risk if you're not careful to use them properly. Below, you'll find a few suggestions that should help you maintain your thread plug gages for reliable and consistent usage. Following these tips is a great way to make sure that you receive accurate measurements every time and can put you in a position to generate reliable results that you know your customers will always be able to count on. Proper Force Application Finding the right balance of force when you use your thread plug gages may feel like a trial and error system, but it's an incredibly important task that you should be sure not to pass up. If you apply too much pressure, your gages could damage the threaded connection they're attempting to measure. On occasion, damage to the gages themselves may occur, leaving you struggling to determine if your readings are as accurate as you want them to be. Professionally constructed thread plug gages will be sure to fit snugly into a threaded hole without any force or cajoling necessary. One good way to make sure you don't accidentally end up misapplying force is to only have the gage available that is specifically designed to fit into a specific slot. This way, there's no risk of picking up and improperly sized tool and forcing it where it doesn't go, and you can be sure that your tools and your inventory will both remain strong and reliable. Full Length Measurements Some of the biggest stresses on the tips of your thread plug gages come in the insertion and removal process. If your attempts to expedite your checking process involve you using one gage many times in rapid succession, you may be more likely to cause structural damage to the gage and, simultaneously, receive inaccurate measurements. This method can also leave you vulnerable to manufacturing deficiencies which may appear further down a threaded shaft. Be sure to use your thread plug gages to measure the full length of a threaded surface if at all possible. Some connection points are designed to be shallow and thus won't be able to accept the full gage, and in those cases, it's important to follow the suggestions above about proper force. When available, however, using the full surface of your gage may be the best way to receive accurate readings. Utilizing Both Ends Both the "go" and "no go" ends of your thread plug gage fulfill a vital role in verifying the strength and usability of a given component. Putting too much repetitive stress on one end of the gage, as mentioned above, can put you in a position where it quickly wears down. Even with proper storage, you may find yourself with a damaged gage that suddenly risks the integrity of your operation. Rather than settling for substandard results, checking both threads and rings with both ends of your thread plug gage will help guarantee repeated results that allow for customer satisfaction in every component. Rather than processing returns and new runs, you can be confident that your manufacturing process will be successful the first time. The experts at WESTport Corporation will help guarantee you have access to the precise gage that will meet your manufacturing needs. Relying on our expertise is the first step in securing your manufacturing process for many years to come.

If you are interested in engineering and manufacturing, you may have heard of thread and plug gages, but weren't really sure what they were used for. While you may have been eager to create products using CAD/CAM devices, these gages are used to make physical inspections for fasteners (e.g. screws, nuts, bolts). You can use gages to make sure that these fasteners fit nicely together. Take a look at how these tools are used and how tolerant they are to wear and tear. Thread Gages Thread gages—also known as pitch gages—are used to check the pitch of a thread (the helical structure) on a screw or a working piece's hole. However, the word "pitch" can be a little misleading. Instead of referring to the height of these threads, the pitch is referring to the the number of threads per inch or centimeter and how close they are to one another. There are different thread gages on the market: some look like rods while others look almost like pocket knives. The ones that look like rods are sometimes called go-no-go instruments. That's because one end of the gauge will have a GO end and a NO-GO end. The GO end should fit cleanly into a nut, while the NO GO end should be stopped by the nut. The ones that look like pocket knives have various blades. Each blade has a triangular serration that will correspond with differences in pitch. Although both tools don't give you exact measurements, they will allow you to roughly figure out the right pitch and see if a screw will fit fairly cleanly with another threaded material. Plug Gages While thread gages check the helical structures of a working part, plug gages check whether or not a given dimension (like a hole) is too large or small. These tools look like rods and also have a GO end and a NO-GO end. Again, if the hole has correct dimensions, then the GO end should enter easily while the NO-GO end should be stopped. Tolerances of Both While Gages are often made of steel, that doesn't mean they are impenetrable. You may want to look for products that have tungsten-carbide coats or extra plating to make sure they are more durable. Even with increased durability, threaded gages should never be forced into a part with too much rotational force—a couple of turns should be sufficient. If the GO end isn't fitting into the hole, clearly the pitch isn't correct. If you use too much rotational force, you could damage the gage. Also, both threaded gages and plug gages are subject to a phenomenon called galling, or col-welding, where surfaces are placed under pressure and began to expand, causing a nut and bolt to permanently weld together! You can prevent galling from occurring by making sure that your gages are well lubricated with oil. You should also look for triple-cold stabilization, which means that the gages have been frozen and thawed and can withstand galling. Lastly, look for any debris that has stuck to your gages. Tiny chips from burred materials can actually adhere to the surface of gages and cause warping and galling. For more information, contact companies like WESTport.   18 April 2017  

ACME Thread Ring Gages Taperpipe Thread Ring Gages Straight Pipe Thread Ring Thread Ring Gages ANPT Thread Ring Gages Pg Conduit Thread Ring Gages Unified Miniature Screw Thread Ring Gages WESTport Gage provides a comprehensive line of Thread Ring Gages to meet all of your gaging needs. Click on any of the links below for a detailed product description along with pricing. For your convenience you can order online, email us at info@westportcorp.com with any technical questions, visit our website www.westportcorp.com or call us at 800-876-8587 and one of our friendly team members will gladly assist you. ACME Thread Ring Gages ACME Threads are used for translation motion in machine tools like lead screws where rapid movement is required or in screw jacks, where load to be shared is more. WESTport Gage provides a complete line of standard and special General Purpose ACME GO/NO GO Thread Ring Gages in compliance with ASME B1.5 - 1997. Acme Thread Ring Gages are used to gage an external threaded product. There are three classes of fit for ACME General Purpose thread gages; 2G, 3G and 4G. Taperpipe Thread Ring Gages NPT THREADS are used in general purpose application of pipe assembly, where a pressure tight joint of pipes is made, by making the pipes wrench tight using a sealing compound. NPT L1 taper pipe ring gages are used to check external threaded parts. NPT L1 rings inspect the functional size or hand tight engagement of the pipe, nipple or male threads. NPTF L1 ring gages are used to check external threaded parts. NPTF L1 ring gages inspect the functional size or hand tight engagement of the pipe, nipple or male threads. NPTF gages are used to inspect pipe threads that are used in Dryseal applications NPTF (Dryseal) NPTF 6 step ring gages check the crest truncation or profile of the external threads and are used in conjunction or relationship with the L1 ring. Straight Pipe Thread Ring Gages Straight pipe thread ring gages are manufactured per ANSI/ASME B1.20.1. The threads are designed for free fitting mechanical joints. Straight pipe thread gages include NPSM, NPSF, NPSC, NPSL, NPSI, NPSH, and NH sizes. Thread Ring Gages Thread ring gages are adjustable and used to measure threads on an outside diameter (OD) to ensure the threads are within its designed tolerance limits. They are manufactured to an X tolerance and American Gage Design standards (AGD). Available in GO or NOGO, Class 2A or 3A for inch and to X Tolerance, Class 6g for metric. ANPT Thread Ring Gages WESTport provides a complete range of Aeronautical National Form Taper Pipe Thread Ring Gages per SAE AS71051. ANPT thread ring gages are intended for use on pipe, rings, fittings, and similar devices in aeronautical components and equipment requiring a sealed thread joint and where straight threads and gaskets or O‐rings are inadequate. Pg Conduit Thread Ring Gages Checks threads of pipe fittings used for electrical wiring. Pg Steel Conduit Thread Ring Gages are manufactured per DIN 40431 and inspect conduit threads. Miniature Thread Ring Gages Unified Miniature Screw thread ring gages are intended for use in watches, instruments, and miniature mechanisms. They provide a full range of Unified Miniature Screw Thread Ring Gages per the American Standard B1.10M 2004 and the equivalent ISO Recommendation.

Thread plug gage – GO and NOGO A person new to the inspection and metrology of threaded parts finds a wide range of gage types existing in the inspection of screws and nuts. The terminology and significance can be confusing. This article will help explain this in a simple way. In a production shop, the inspection of cylindrical parts (shafts or holes) for passing inspection is done quickly using a GO and NO-GO snap gauge ring gages (for checking shafts) or plug gages (for checking holes). They are simple and easy to understand the usage of them. In the case of (screw/bolt) threaded parts, thread plug gages are used in production shops where the “screws” (externally threaded parts) or the “nuts” (internally threaded parts) are to be quickly checked for inspection and approval. When you consider the metrology (the science of measurement) of threaded parts as a whole, more than a couple of thread gage types are involved; a novice in metrology can become somewhat confused with the terminology of the threaded gages in addition to how they are used. In a threaded part, several features are involved – the thread’s major diameter, minor diameter, pitch diameter, pitch (in case of metric threads) or threads per Inch (TPI in case of Standard American Equivalent (SAE) threads), flank angle, etc. Normally, a GO / NO-GO type of threaded gage will inspect a threaded part based mainly on the pitch diameter. As long as a GO gage is answered (threads properly without being forced) and a NO-GO gauge is not answered, the threaded part is deemed to be accepted and pass inspection. In some specific cases where the thread major diameter (for screws) or minor diameter (for nuts) is critical, separate, plain GO/ NOGO gages (like those used for measuring cylindrical parts) are also used in addition to a threaded gages to determine the acceptance of a threaded part. A thread plug gage is used to check acceptance of a “nut” , (an internally threaded part). For small threaded parts, the gage will be double ended, with one end carrying the GO gage and the other end, the NOGO. For larger parts, the two may be separate pieces. A thread plug gage is designed to check the pitch diameter (to the given pitch / Threads per inch). In order for the part to pass inspection and be accepted, the GO gage should pass through the entire length of the nut, without requiring the use of too much rotational force. The NOGO gage can at the best enter into the nut, checked at both ends, over not more than 2 turns. It should not go beyond this. If you should need additional information or have any technical questions, please feel free to call us at 888-400-4243, visit us at www.westportcorp.com or email us at info@westportcorp.com

Thread plug gages are used to check tolerances of threaded parts according to a certain specification. These highly specific calibration tools are used to assure the assembly of mating parts and provide quality control and conformity to standards. Most gages have two ends: a GO and a NO GO. The GO end must screw all the way on, while the NO GO end must not. The class of fit for each gage measures the amount of tolerance allowed for that class. For example, class 1A has the greatest range of tolerance for unified external screw threads. It is used mainly for parts that need to be assembled quickly and easily, while classes 2A and 2B are the most common and provide a more specific calibration. Class 3A has the closest tolerance and is used for very specific calibrations where safety or strength are concerned. Classes of fit and tolerance vary, so carefully select the class needed for your specific use. Many types of thread gages exist for many different purposes; see below for descriptions. ACME Thread Plug Gages: This gage is used to check an internally threaded product. Compliant to ASME B47.1 and B1.5-1997, this gage also comes in three classes of fit: 2G, 3G, and 4G. It also is available with three centralizing ACME threads classes of fit: 2C, 3C, and 4C. Flexible Hole Location Plug Gages: Use this gage to inspect the location of a threaded hole in a part and determine the true centerline-to-centerline distances of threaded holes. It is also slotted at 90⁰ increments to ensure a positive location on the thread flanks, regardless of hole size. The center is concentric to the threaded section within .0002’ TIR for probe location of CMM’s. This product is available in unified and metric sizes. Every gage is inspected in an environmentally controlled ISO 17025 laboratory. ACME Thread Set Plug Gages: This gage is used to calibrate adjustable style matching ACME thread ring gages. Available in three classes of fit, choose from 2G, 3G, and 4G. Its Centralizing ACME threads classes of fit: 2C, 3C, 4C. Compliant with ASME B1.5-1997 and B47.1. Helical Coil Thread Plug Gages: STI Thread plug gages are used to gage threaded holes prior to the insertion of screw thread inserts. This gages is very commonly used in the automotive industry. All WESTport Gage Corporation helical coil thread plug gages are class X tolerance and class 2B or 3B. They are GO or NO GO plug members and ASME/ANSI B1.2 compliant. All gages are inspected in an environmentally controlled ISO 17025 laboratory. Straight Pipe Thread Plug Gages: Straight pipe working plug gages are used to check the size of the internal threads of a part. Use this gage to calibrate and set a straight pipe thread ring. It can also be used to inspect the ring gage for wear. Features GO or NO GO members. All straight pipe thread plug gages are inspected in an environmentally controlled ISO 17025 laboratory. Taperpipe Plug Gages: The NPT L1 and the NPTF L1 plugs inspect the functional size or hand tight engagement of couplings or an internal thread. Or the NPTF L3 plug inspects the wrench engagement and taper of couplings or internal threads and is used in conjunction with the L1 plug. Additionally, the NPTF 6 step plug inspects the crest truncation or profile of the internal threads and is used in conjunction with L1 plug. All NPT pipe thread plug and ring gages are manufactured per ANSI/ASME B1.20.1, and all NPTF pipe thread plug gages are manufactured per ANSI/ASME B1.20.5. Taperlock Thread Plug Gages: This gage checks the size of internal threads to ensure the threads are within its designed tolerance limits. It features GO and/or NO GO thread plug members. All taperlock thread plug gages are class X tolerance. Choose from class 2B or 3B for inch, or class 6H of fit for metric thread plugs. Truncated Setting Plug Gages: Use this gage to calibrate and set an adjustable thread ring gage and inspect it for wear. The crest of the thread is truncated in diameter for the first half of the set plug and “full form” on the remaining length. The truncated section is used to set the pitch diameter, and the full form section detects flank angle problems or undersize major diameters in the thread rings. Reversible Trilock Thread Plug Gages: This gage checks the size of the internal threads to make sure that are within designed tolerance limits. It’s best for larger thread plug gages—1 ½ inches or larger. The reversible gage members provide two gages for the price of one. It features GO and/or NO GO members, class X tolerance, and a chip groove on the GO member to make identification easy. Reversible Thread Plug Gages: Use this gage to ensure that internal thread are within the designed tolerance limits. This gage features GO and NO GO plug members, class X tolerance, and ASME/ANSI B1.2 and B1.16M compliance. Reversible gages provide two gages for the price of one. Variable Thread Gages: This class “W” gage is full form for use with TRI-ROLL and STC Comparators. Variable thread gages are an economical choice compared to GO/No GO gages because of the reduced gaging time. Variable thread gages are for use with ASME B1.3M Systems 21 and 22. Written by Kate Hansen, Edited by Robert Forbes – WESTport Corporation – January 22, 2015

This is the second part of an article on thread gauges. In Part:1 of the article, we covered thread plugs, thread ring and caliper gauges, which are mostly used in shops for the checking of threaded parts. In this part, we shall see the other thread gauges, which are mostly used in Standards Room. Thread Gauges Used for Checking Basic Thread Gauges What will happen if the thread gauges used on the shop floor get worn out due to constant usage? Thread gauges need to be periodically calibrated in the Standards Room to check whether the gauges are still in usable size range. Inspecting and physically measuring the dimensions of a “male gauge" i.e. a thread plug gauge, is rather easy, because the pitch diameter is easily amenable for metrological measurements in the Standards Room. But physically measuring a “female gauge," namely, a thread ring gauge is not at all easy. When a new ring gauge is made, how then is it checked for correctness? After some usage, how is the ring gauge checked to see whether it is worn beyond limits? What is the practical way out? That’s where “Check plug gauges" come into picture. A new thread ring gauge is basically just a “nut" with much closer tolerances. So, this “nut" can be easily inspected by another thread plug gauge, with still stricter tolerances and that’s precisely what the “Check plug gauges" are designed for. i) Check plugs for new thread ring gauges GO and NO-GO: We have already seen that we have thread rings gauges to check GO and NO-GO. So, naturally, we require Check plug gauges to check the newly made GO ring gauge and also the NO- GO ring gauge. These check plugs will each have a GO and NO-GO member. But there is a small concession. ii) Wear Check plugs for used thread ring gauges GO and NO-GO: We require one wear check plug for the GO thread ring and another for the NO-GO thread ring gauge. A wear check plug is only a NO-GO device. What this means is that a wear check plug should not enter into the thread ring more than one turn on either end of the ring. Now we shall see what the “concession" that we mentioned earlier is. When a Wear check plug for the NO-GO thread ring is available, a separate NO-GO check plug for the ring is not necessary. i.e., just a GO check plug alone is good enough for the new NO-GO ring. The wear check plug itself can be used as though it is a NO-GO check plug. Though it may be a bit confusing when you read all these for the first time, it is really not too difficult grasp these finer aspects if you read the above paragraphs a second time. iii) Setting plugs for adjustable thread ring gauges: We have seen under (c) that there are adjustable ring gauges in use and they are required to be set to the correct size. For that purpose, there will be a GO sized setting gauge and a NO-GO sized setting gauge for the ring gauges. After setting, they have to be checked with respective NO-GO Check Plugs for non-entry. iv) Setting plugs for thread caliper gauges: We have seen under (d) that there are thread caliper gauges in use and they are required to be set to the correct size. For that purpose, there will be a GO sized setting gauge and a NO-GO sized setting gauge for the caliper gauges. The correct setting is when the setting gauges smoothly pass through the gauges using gravity alone. All the above gauges cover most of the gauging requirements for threaded parts and for gauge manufacture and calibration. Before we wind up, let us also look into another gauge popularly in use. v) A thread pitch gauge: A thread pitch gauge is a visual checking device to identify the pitch of a threaded part and it is NOT a typical metrology/inspection device. When you come across a new screw or a nut and you are not sure whether it is a metric thread, British thread, or any other thread and you need to quickly check the pitch and, to an extent, the profile, you can make use of a thread pitch gauge. A pitch gauge usually comes as a set of thin plates or leafs, with hacksaw-like teeth precisely machined to a given thread pitch (or TPI – threads per inch) and thread profile (specific flank angle and tooth depth). You have to pick out one plate (leaf) from the gauge, try to match it with the threaded part, and if it does not sit snugly, try another plate in the gauge. When all the teeth in a specific gauge leaf sit properly on the part being measured (ie without a gap), you can read the pitch size engraved in the leaf of the gauge in use. By looking at the light-passing between the gauge and the part, you can, to some extent, decide about the matching of the flank angle of the thread as well. But a pitch gauge is not a one hundred percent foolproof device to check and determine a thread pitch and type. Unless the inspector is experienced, there is the possibility of making a mistake in determining the correct pitch/ thread type, particularly if the thread is too fine and the pitch happens to be close to a nearby metric /SAE size thread. Again: a pitch gauge is only a visual comparator. It does not decide acceptance or non-acceptance of a threaded part like a GO/NO-GO gauge. It is not a metrology device in the strictest sense. Fig.a Thread Pitch Gauge Written by: Mike Aguilar • edited by: Lamar Stonecypher • updated: 10/8/2011

A person new to the inspection and metrology of threaded parts finds a plethora of gauge types existing in the inspection of screws and nuts. Their terminology and significance can be confusing, but this article is meant to explain them in a simple way. In production shops, the inspection of cylindrical parts (shafts or holes) for acceptance is quickly done using simple GO and NO-GO snap/ring gauges (for checking shafts) and plug gauges (for checking holes). They are mostly simple and easy to comprehend. In the case of (screw/bolt) threaded parts, thread gauges are used in production shops where the “screws" (externally threaded parts) or the “nuts" (internally threaded parts) are to be quickly checked for acceptance. But when you consider the metrology (the science of measurement) of threaded parts as a whole, more than a couple of thread gauge types are involved; a novice in metrology may become somewhat confused with the terminology of the threaded gauges, their application, and their usage. In this article, we shall try to understand the various types of thread gauges and their applications. This article deals with thread gauges used primarily in the shop for acceptance gauging of threaded parts. Before that, a word about thread gauging practice: In a threaded part, several features are involved – the thread’s major diameter, minor diameter, pitch diameter, pitch (in case of metric threads) or threads per Inch (TPI in case of Standard American Equivalent (SAE) threads), flank angle, etc. Normally, a GO / NO-GO type of threaded gauge will inspect a threaded part based mainly on the pitch diameter. As long as a GO gauge is answered (threads properly without being forced) and a NO-GO gauge is not answered, the threaded part is deemed to be accepted in totality. But in some specific cases where the thread major diameter (for screws) or minor diameter (for nuts) is critical, separate, plain GO/ NO-GO gauges (as those used for measuring cylindrical parts) are also used in addition to a threaded gauges to determine the acceptance of a threaded part. A) Thread plug gauge (GO and NO-GO) A thread plug gauge is used to check acceptance of a “nut" – i.e. an internally threaded part. For small threaded parts, the gauge will be double ended, with one end carrying the GO gauge and the other end, the NO-GO. For large parts, the two may be separate pieces. A thread plug gauge is designed to check the correctness of the pitch diameter (to the given pitch / TPI). For acceptance of the part, the GO gauge should pass through the entire length of the nut, without requiring the use of too much rotational force. The NO-GO gauge can at the best enter into the nut, checked at both ends, over not more than 2 turns and NOT beyond. (Fig:1 A thread Plug gauge) B) Solid Thread Ring Gauge (GO and NO-GO): A solid thread ring gauge is used to check acceptance of a “screw" – i.e. externally threaded part. The GO and NO-GO rings are normally separate pieces. A thread ring gauge is designed to check the correctness of the thread, to include thread depth and pitch diameter (to the given pitch / TPI). For acceptance of the part, the GO ring gauge should pass through the entire length of the screw, without too much use of force. Ideally, the screw or bolt will thread completely through the gauge relatively easily. The NO-GO ring gauge can at the best enter into the screw over not more than 2 rotations and NOT beyond. C) Adjustable Thread Ring Gauge (GO and NO-GO): These gauges, too, are ring shaped, but they have a split and an adjusting and locking screw facility to finely adjust their right gauging size. For setting these gauges, “Setting plugs" are needed, which are discussed later. Fig:2 Thread ring gauge Fig:3 Adj. Ring Gauge Fig:4 construction of Ad. Ring gauge D) Thread caliper gauges (GO/ NO-GO) Though an external threaded part is best checked with a thread ring gauge, the use of thread caliper gauges (which are also called thread snap gauges) is also in practice. Some caliper gauges may be designed with roller type GO elements, which facilitate quick inspection by simple sliding of the threaded part, using gravity, through the GO rollers. Though not as accurate as ring gauges in inspection, thread caliper gauges are preferred in mass production areas where screws need to be inspected considerably faster. A caliper gauge is much quicker for inspection as the parts are slid through the gauge rather than screwing-in as in ring gauges. The wear and tear thread caliper gauges is also less. However, in places where caliper gauges are used, it is normally recommended to also have an additional thread ring gauge set, to perform inspection on random samples and ensure an additional layer of quality assurance. Caliper gauges require “setting plugs" to set them to correct inspecting size which are discussed later in this article. Fig: 5 Thread Caliper Gauge The above four types of gauges are used on the shop floor for acceptance of threaded parts. In the next part of this article, we shall cover other thread gauges which are used mostly in the Standards Room, for checking and calibration of the aforesaid thread gauges. Reference http://www.brighthubengineering.com/manufacturing-technology/45357-understanding-thread-gauges-part-one/ Written by: Mike Aguilar • edited by: Lamar Stonecypher • updated: 10/8/2011

Keeping up with all of the different types of hydraulic systems, fittings, adapters, and sealing methods is no easy feat. Throw thread forms into the mix, and you can find yourself in several situations where it would be easy to make a mistake. And we all know what can happen if you make a mistake and select the wrong part – safety hazards, lost time, and lost money among other things. There are six types of threads that are commonly found on hydraulic tube fittings which industry professionals should know how to identify quickly and accurately. UN/UNF NPT/NPTF BSPP (BSP, Parallel) BSPT (BSP, Tapered) Metric Parallel Metric Tapered There are five strategies to identifying thread forms to ensure you are picking the right replacement part when making repairs and performing regular maintenance. Step 1 Determine if the fitting is male or female. This is the easiest identification step; all you have to do is locate the threads. A male fitting will have the threads on the outside, while a female fitting will have the threads on the inside of the hex nut. Step 2 Eliminate 3 out of the 6 different types of threads by determining whether it is tapered or parallel. This is another step that can easily be accomplished with a quick visual inspection. Parallel threads are the same diameter from end to end, while the diameter of tapered threads gets smaller towards the end of the fitting. UN/UNF and BSPP fittings have parallel threads, and NPT/NPTF and BSPT fittings have tapered threads. If it’s too hard to tell by looking, use a caliper. Step 3 Decipher the pitch by measuring from one crest of the thread to the next crest or measuring how many crests are in an inch of thread. You can do this by using a pitch gage against a lighted background. Make sure to measure multiple pitches to be sure. Step 4 Find out the thread size. You can determine the size of pipe threads (NPT/NPTF, BSPT, BSPP) by measuring the outer diameter and comparing it with the profile, or in other words, by subtracting ¼ inch. For non-pipe threads (UN/UNF, Metric Parallel, Metric Tapered), determine the size by measuring the outer diameter using a caliper. Step 5 Define the thread by the information you now know. For example, list a thread by the thread type, a parallel or tapered thread, the pitch (distance between each thread), and the size of the thread. May 1, 2013 Marissa

When you make the decision to operate an industrial assembly line, you're taking on broader responsibility than simply maximizing your own profits. The items you produce will likely be counted on by numerous industries for highly specific applications, so it's absolutely essential that your production line operates at the highest possible level of accuracy. In order to achieve that goal, you need to make sure that your equipment is properly calibrated and able to produce accurate products to exact design specifications. While there are a number of technologies on the market which purport to be of assistance in this area, thread plug gauges truly stand as the gold standard. Below, you'll find a guide to some of the advantages of using thread plug gauges in your manufacturing operation. Keeping these advantages in mind can help you modernize your setup and can guarantee that you'll be prepared to build a strong reputation that grows your client base for years to come. Ease of Usage Efficiency should be one of the primary goals for any person involved in overseeing an industrial firm. If you purchase unreliable tools that leave your employees struggling to verify their work, you could actually be creating unnecessary and unwelcome delays in your attempt to provide assistance. Even the most skilled laborers will be unable to keep up with the pace of production if they're at the mercy of inefficient tools. Thread plug gauges can provide easy and accurate measurements with no need for skepticism about the results. Whatever your choice of materials, your plug gauges will remain highly adaptable and accurate in the hands of your labor force. Efficient tools can lead to enhanced productivity and faster turn-around times. This in turn can help you achieve consistent results that will keep your employees and clients equally satisfied about the speed and quality of the work that's performed. Relative Affordability Another difficult challenge for a business operator is determining the proper amount to invest in a business while being sure that that investment is generating a return. If you find yourself purchasing expensive calibration equipment that eats into your profit margins, the accuracy of your products becomes far less reliable. If you have to drive your prices through the roof in order to cover your operating costs, your customers will be forced to look elsewhere. Your thread plug gauges are designed to operate in a rough and tumble environment, and for that reason, they may be substantially less expensive than other kinds of highly technical equipment. This doesn't suggest that the plug gauges are intended to be disposable or that they don't require special care; indeed, one of the reasons that thread plug gauges remain a cost effective solution is because they have a long life with a built-in wear tolerance that's designed to withstand difficult challenges. Coating Options In order to generate the best possible performance, you might have special materials requirements. If you need to operate your gauges at high temperatures or within certain electrical tolerances, it's important to know there are products available that can provide you with that level of service. You'll be able to work with your supplier to order thread plug gauges that offer the proper coating. Those coating options can allow you to always have the right tool for the job, and can guarantee that you avoid any risk of damage that might come with a more blunt instrument. WESTport can provide you with custom gauge solutions to fulfill your every need. Leaning on the skills and experience of an industry leader can help your operation run smoothly and can secure the future of your company for many years to come.  

Standard Pitch Diameters - Metric Thread Gages

  Thread Plug Gages   BASIC THREAD DESIGNATION DIMENSIONS IN MILLIMETERS DIMENSIONS IN INCHES NOMINAL O.D. PITCH MAJOR DIA. PITCH DIA. MINOR DIA. NOMINAL O.D. THREADS PER INCH MAJOR DIA. PITCH DIA. MINOR DIA. MIN. (MUST CLEAR) MIN. GO MAX. HI MIN. MAX. MIN. (MUST CLEAR) MIN. GO MAX. HI MIN. MAX. M1.6x0.35 1.6 0.35 1.600 1.373 1.458 1.221 1.321 .06299 72.57 .06299 .05406 .05740 .04807 .05201 M2x0.4 2.0 0.40 2.000 1.740 1.830 1.567 1.679 .07874 63.50 .07874 .06850 .07205 .06169 .06610 M2.5x0.45 2.5 0.45 2.500 2.208 2.303 2.013 2.138 .09843 56.44 .09843 .08693 .09067 .07925 .08417 M3x0.5 3.0 0.50 3.000 2.675 2.775 2.459 2.599 .11811 50.80 .11811 .10531 .10925 .09681 .10232 M3.5x0.6 3.5 0.60 3.500 3.110 3.222 2.850 3.010 .13780 42.33 .13780 .12244 .12685 .11220 .11850 M4x0.7 4.0 0.70 4.000 3.545 3.663 3.242 3.422 .15748 36.29 .15748 .13957 .14421 .12764 .13472 M5x0.8 5.0 0.80 5.000 4.480 4.605 4.134 4.334 .19685 31.75 .19685 .17638 .18130 .16276 .17063 M6x1 6.0 1.00 6.000 5.350 5.500 4.917 5.153 .23622 25.40 .23622 .21063 .21654 .19358 .20287 M8x1.25 8.0 1.25 8.000 7.188 7.348 6.647 6.912 .31496 20.32 .31496 .28299 .28929 .26169 .27213 M8x1 8.0 1.00 8.000 7.350 7.500 6.917 7.153 .31496 25.40 .31496 .28937 .29528 .27232 .28161 M10x1.5 10.0 1.50 10.000 9.026 9.206 8.376 8.676 .39370 16.93 .39370 .35535 .36244 .32976 .34157 M10x1.25 10.0 1.25 10.000 9.188 9.348 8.647 8.912 .39370 20.32 .39370 .36173 .36803 .34043 .35087 M10x0.75 10.0 0.75 10.000 9.513 9.645 9.188 9.378 .39370 33.87 .39370 .37453 .37972 .36173 .36921 M12x1.75 12.0 1.75 12.000 10.863 11.063 10.106 10.441 .47244 14.51 .47244 .42768 .43555 .39787 .41106 M12x1.5 12.0 1.50 12.000 11.026 11.216 10.376 10.676 .47244 16.93 .47244 .43409 .44157 .40850 .42031 M12x1.25 12.0 1.25 12.000 11.188 11.368 10.647 10.912 .47244 20.32 .47244 .44047 .44756 .41917 .42961 M12x1 12.0 1.00 12.000 11.350 11.510 10.917 11.153 .47244 25.40 .47244 .44685 .45315 .42980 .43909 M14x2 14.0 2.00 14.000 12.701 12.913 11.835 12.210 .55118 12.70 .55118 .50004 .50839 .46594 .48071 M14x1.5 14.0 1.50 14.000 13.026 13.216 12.376 12.676 .55118 16.93 .55118 .51283 .52031 .48724 .49906 M15x1 15.0 1.00 15.000 14.350 14.510 13.917 14.153 .59055 25.40 .59055 .56496 .57126 .54791 .55720 M16x2 16.0 2.00 16.000 14.701 14.913 13.835 14.210 .62992 12.70 .62992 .57878 .58713 .54469 .55945 M16x1.5 16.0 1.50 16.000 15.026 15.216 14.376 14.676 .62992 16.93 .62992 .59157 .59906 .56598 .57780 M17x1 17.0 1.00 17.000 16.350 16.510 15.917 16.153 .66929 25.40 .66929 .64370 .65000 .61886 .63594 M18x1.5 18.0 1.50 18.000 17.026 17.216 16.376 16.676 .70866 16.93 .70866 .67031 .67780 .64472 .65654 M20x2.5 20.0 2.50 20.000 18.376 18.600 17.294 17.744 .78740 10.16 .78740 .72346 .73228 .68087 .69858 M20x1.5 20.0 1.50 20.000 19.026 19.216 18.376 18.676 .78740 16.93 .78740 .74906 .75654 .72346 .73528 M20x1 20.0 1.00 20.000 19.350 19.510 18.917 19.153 .78740 25.40 .78740 .76181 .76811 .74476 .75406 M22x2.5 22.0 2.50 22.000 20.376 20.600 19.294 19.744 .86614 10.16 .86614 .80220 .81102 .75961 .77732 M22x1.5 22.0 1.50 22.000 21.026 21.216 20.376 20.676 .86614 16.93 .86614 .82780 .83528 .80220 .81402 M24x3 24.0 3.00 24.000 22.051 22.316 20.752 21.252 .94488 8.47 .94488 .86815 .87858 .81701 .83669 M24x2 24.0 2.00 24.000 22.701 22.925 21.835 22.210 .94488 12.70 .94488 .89374 .90256 .85965 .87441 M25x1.5 25.0 1.50 25.000 24.026 24.226 23.376 23.676 .98425 16.93 .98425 .94591 .95378 .92031 .93213 M27x3 27.0 3.00 27.000 25.051 25.316 23.752 24.252 1.06299 8.47 1.06299 .98626 .99669 .93512 .95480 M27x2 27.0 2.00 27.000 25.701 25.925 24.835 25.210 1.06299 12.70 1.06299 1.01185 1.02067 .97776 .99252 M30x3.5 30.0 3.50 30.000 27.727 28.007 26.211 26.771 1.18110 7.26 1.18110 1.09161 1.10264 1.03193 1.05398 M30x2 30.0 2.00 30.000 28.701 28.925 27.835 28.210 1.18110 12.70 1.18110 1.12996 1.13878 1.09587 1.11063 M30x1.5 30.0 1.50 30.000 29.026 29.226 28.376 28.676 1.18110 16.93 1.18110 1.14276 1.15063 1.11717 1.12898 M33x2 33.0 2.00 33.000 31.701 31.925 30.835 31.210 1.29921 12.70 1.29921 1.24807 1.25689 1.21398 1.22874 M35x1.5 35.0 1.50 35.000 34.026 34.226 33.376 33.676 1.37795 16.93 1.37795 1.33961 1.34748 1.31402 1.32559 M36x4 36.0 4.00 36.000 33.402 33.702 31.670 32.270 1.41732 6.35 1.41732 1.31504 1.32685 1.24685 1.27047 M36x2 36.0 2.00 36.000 34.701 34.925 33.835 34.210 1.41732 12.70 1.41732 1.36618 1.37500 1.33209 1.34685 M39x2 39.0 2.00 39.000 37.701 37.925 36.835 37.210 1.53543 12.70 1.53543 1.48429 1.49311 1.45020 1.46496 Frequently Asked Questions About This Pitch Diameter Chart What is the significance of pitch diameter in thread measurement? Pitch diameter is crucial as it determines the actual diameter at which the threads of the bolt and nut intersect, providing a baseline for whether a thread will fit correctly and perform its intended function. How does the pitch diameter affect thread quality and performance? A correct pitch diameter ensures that the threads engage properly, allowing for optimal strength, security, and durability of the threaded connection. It impacts load distribution and stress concentration on the threads. Why are there different pitch diameters for the same nominal size? Different thread profiles and standards (such as ISO, UN, etc.) have varying designations for pitch diameter to accommodate specific applications, tolerances, and materials, ensuring the best fit and performance across diverse engineering needs. Can the pitch diameter chart be used for both inspection and manufacturing? Yes, the thread plug gage pitch diameter chart is valuable for both inspection and manufacturing processes. It guides the manufacturing of thread plug gages and helps in inspecting the threaded parts to ensure they meet the specified tolerances. How do I select the correct thread plug gage based on the chart? Identify the nominal size and thread type of your component. Then, use the chart to find the corresponding pitch diameter for the specific tolerance class to select the correct thread plug gage.

Thread Plug Gages NOMINAL SIZE GO BASIC ALL CLASSES ALL SERIES UNIFIED PITCH DIAMETERS NOT GO X TOL.GO =+NO GO=– XLEADTOL. X ±HALFANGLETOL. CL. 2B CL. 3B #0 - 80 UNF .0519 .0542 .0536 .0002 .0002 0°30' #1 - 64 UNC .0629 .0655 .0648 .0002 .0002 0°30' #1 - 72 UNF .0640 .0665 .0659 .0002 .0002 0°30' #2 - 56 UNC .0744 .0772 .0765 .0002 .0002 0°30' #2 - 64 UNF .0759 .0786 .0779 .0002 .0002 0°30' #3 - 48 UNC .0855 .0885 .0877 .0002 .0002 0°30' #3 - 56 UNF .0874 .0902 .0895 .0002 .0002 0°30' #4 - 40 UNC .0958 .0991 .0982 .0002 .0002 0°20' #4 - 48 UNF .0985 .1016 .1008 .0002 .0002 0°30' #5 - 40 UNC .1088 .1121 .1113 .0002 .0002 0°20' #5 - 44 UNF .1102 .1134 .1126 .0002 .0002 0°20' #6 - 32 UNC .1177 .1214 .1204 .0003 .0003 0°15' #6 - 40 UNF .1218 .1252 .1243 .0002 .0002 0°20' #8 - 32 UNC .1437 .1475 .1465 .0003 .0003 0°15' #8 - 36 UNF .1460 .1496 .1487 .0002 .0002 0°20' #10 - 24 UNC .1629 .1672 .1661 .0003 .0003 0°15' #10 - 32 UNF .1697 .1736 .1726 .0003 .0003 0°15' #12 - 24 UNC .1889 .1933 .1922 .0003 .0003 0°15' #12 - 28 UNF .1928 .1970 .1959 .0003 .0003 0°15' #12 - 32 UNEF .1957 .1998 .1988 .0003 .0003 0°15' 1/4 - 20 UNC .2175 .2224 .2211 .0003 .0003 0°15' 1/4 - 28 UNF .2268 .2311 .2300 .0003 .0003 0°15' 1/4 - 32 UNEF .2297 .2339 .2328 .0003 .0003 0°15' 5/16 -18 UNC .2764 .2817 .2803 .0003 .0003 0°10' 5/16 - 24 UNF .2854 .2902 .2890 .0003 .0003 0°15' 5/16 - 32 UNEF .2922 .2964 .2953 .0003 .0003 0°15' 3/8 - 16 UNC .3344 .3401 .3387 .0003 .0003 0°10' 3/8 - 24 UNF .3479 .3528 .3516 .0003 .0003 0°15' 3/8 - 32 UNEF .3547 .3591 .3580 .0003 .0003 0°15' 7/16 - 14 UNC .3911 .3972 .3957 .0003 .0003 0°10' 7/16 - 20 UNF .4050 .4104 .4091 .0003 .0003 0°15' 7/16 - 28 UNEF .4143 .4189 .4178 .0003 .0003 0°15' 1/2 - 13 UNC .4500 .4565 .4548 .0003 .0003 0°10' 1/2 - 20 UNF .4675 .4731 .4717 .0003 .0003 0°15' 1/2 - 28 UNEF .4768 .4816 .4804 .0003 .0003 0°15' 9/16 - 12 UNC .5084 .5152 .5135 .0003 .0003 0°10' 9/16 - 18 UNF .5264 .5323 .5308 .0003 .0003 0°10' 9/16 - 24 UNEF .5354 .5405 .5392 .0003 .0003 0°15' 5/8 - 11 UNC .5660 .5732 .5714 .0003 .0003 0°10' 5/8 - 18 UNF .5889 .5949 .5934 .0003 .0003 0°10' 5/8 - 24 UNEF .5979 .6031 .6018 .0003 .0003 0°15' 11/16 - 24 UNEF .6604 .6656 .6643 .0003 .0003 0°15' 3/4 - 10 UNC .6850 .6927 .6907 .0003 .0003 0°10' 3/4 - 16 UNF .7094 .7159 .7143 .0003 .0003 0°10' 3/4 - 20 UNEF .7175 .7232 .7218 .0003 .0003 0°15' 13/16 - 20 UNEF .7800 .7857 .7843 .0003 .0003 0°15' 7/8 - 9 UNC .8028 .8110 .8089 .0003 .0003 0°10' 7/8 - 14 UNF .8286 .8356 .8339 .0003 .0003 0°10' 7/8 - 20 UNEF .8425 .8482 .8468 .0003 .0003 0°15' 15/16 - 20 UNEF .9050 .9109 .9094 .0003 .0003 0°15' 1”- 8 UNC .9188 .9276 .9254 .0004 .0004 0°05' 1”- 12 UNF .9459 .9535 .9516 .0003 .0003 0°10' 1”- 14 UNS .9536 .9609 .9590 .0003 .0003 0°10' 1”- 20 UNEF .9675 .9734 .9719 .0003 .0003 0°15' 1 1/16 - 12 UN 1.0084 1.0158 1.0139 .0003 .0003 0°10' 1 1/16 - 18 UNEF 1.0264 1.0326 1.0310 .0003 .0003 0°10' 1 1/8 - 7 UNC 1.0322 1.0416 1.0393 .0004 .0004 0°05' 1 1/8 - 12 UNF 1.0709 1.0787 1.0768 .0003 .0003 0°10' 1 1/8 - 18 UNEF 1.0889 1.0951 1.0935 .0003 .0003 0°10' 1 3/16 - 12 UN 1.1334 1.1409 1.1390 .0003 .0003 0°10' 1 3/16 - 18 UNEF 1.1514 1.1577 1.1561 .0003 .0003 0°10' 1 1/4 - 7 UNC 1.1572 1.1668 1.1644 .0004 .0004 0°05' 1 1/4 - 12 UNF 1.1959 1.2039 1.2019 .0003 .0003 0°10' 1 1/4 - 18 UNEF 1.2139 1.2202 1.2186 .0003 .0003 0°10' 1 5/16 - 12 UN 1.2584 1.2659 1.2640 .0003 .0003 0°10' 1 5/16 - 18 UNEF 1.2764 1.2827 1.2811 .0003 .0003 0°10' 1 3/8 - 6 UNC 1.2667 1.2771 1.2745 .0004 .0004 0°05' 1 3/8 - 12 UNF 1.3209 1.3291 1.3270 .0003 .0003 0°10' 1 3/8 - 18 UNEF 1.3389 1.3452 1.3436 .0003 .0003 0°10' 1 7/16 - 12 UN 1.3834 1.3910 1.3891 .0003 .0003 0°10' 1 7/16 - 18 UNEF 1.4014 1.4079 1.4062 .0003 .0003 0°10' 1 1/2 - 6 UNC 1.3917 1.4022 1.3996 .0004 .0004 0°05' 1 1/2 - 12 UNF 1.4459 1.4542 1.4522 .0003 .0003 0°10' 1 1/2 - 18 UNEF 1.4639 1.4704 1.4687 .0003 .0003 0°10' How to Read the Standard Pitch Diameter Chart for Thread Plug Gages To use the standard pitch diameter chart for thread plug gages, match the thread size you are working with to the chart's listed sizes. This will provide you with the go/no-go measurements necessary for ensuring your threads meet the specified tolerances for functionality and compatibility. It's a crucial step for quality control in manufacturing and engineering, helping prevent errors in thread sizing that could lead to part failure or incompatibility.

Pg Conduit Thread Plug Gages

The following table defines recommended industry standard sizes for Internal ACME General Purpose Threads per American National Standard ASME/ANSI B1.5. All dimensional data is given in inches. Designation Size Decimal TPI Tol. Class Minor Dia. Pitch Dia. Major Dia. Tap Drill Min. Max. Min. Max. Min. Max. 1/4-16 ACME 0.25 16 2G 0.1875 0.1925 0.2188 0.2293 0.2600 0.2700 0.1875 1/4-16 ACME 0.25 16 3G 0.1875 0.1925 0.2188 0.2237 0.2600 0.2700 0.1875 1/4-16 ACME 0.25 16 4G 0.1875 0.1925 0.2188 0.2223 0.2600 0.2700 0.1875 1/4-16 ACME 0.25 16 5G 0.1875 0.1925 0.2188 0.2216 0.2600 0.2700 0.1875 5/16-14 ACME 0.3125 14 2G 0.2411 0.2461 0.2768 0.2882 0.3225 0.3325 0.2411 5/16-14 ACME 0.3125 14 3G 0.2411 0.2461 0.2768 0.2821 0.3225 0.3325 0.2411 5/16-14 ACME 0.3125 14 4G 0.2411 0.2461 0.2768 0.2806 0.3225 0.3325 0.2411 5/16-14 ACME 0.3125 14 5G 0.2411 0.2461 0.2768 0.2798 0.3225 0.3325 0.2411 3/8-12 ACME 0.375 12 2G 0.2917 0.2967 0.3333 0.3456 0.3850 0.3950 0.2917 3/8-12 ACME 0.375 12 3G 0.2917 0.2967 0.3333 0.3391 0.3850 0.3950 0.2917 3/8-12 ACME 0.375 12 4G 0.2917 0.2967 0.3333 0.3374 0.3850 0.3950 0.2917 3/8-12 ACME 0.375 12 5G 0.2917 0.2967 0.3333 0.3366 0.3850 0.3950 0.2917 7/16-12 ACME 0.4375 12 2G 0.3542 0.3592 0.3958 0.4084 0.4475 0.4575 0.3542 7/16-12 ACME 0.4375 12 3G 0.3542 0.3592 0.3958 0.4017 0.4475 0.4575 0.3542 7/16-12 ACME 0.4375 12 4G 0.3542 0.3592 0.3958 0.4000 0.4475 0.4575 0.3542 7/16-12 ACME 0.4375 12 5G 0.3542 0.3592 0.3958 0.3992 0.4475 0.4575 0.3542 1/2-10 ACME 0.5 10 2G 0.4000 0.4050 0.4500 0.4637 0.52 0.5400 0.4000 1/2-10 ACME 0.5 10 3G 0.4000 0.4050 0.4500 0.4564 0.52 0.5400 0.4000 1/2-10 ACME 0.5 10 4G 0.4000 0.4050 0.4500 0.4546 0.52 0.5400 0.4000 1/2-10 ACME 0.5 10 5G 0.4000 0.4050 0.4500 0.4537 0.52 0.5400 0.4000 5/8-8 ACME 0.625 8 2G 0.5000 0.5062 0.5625 0.5779 0.645 0.6650 0.5000 5/8-8 ACME 0.625 8 3G 0.5000 0.5062 0.5625 0.5697 0.645 0.6650 0.5000 5/8-8 ACME 0.625 8 4G 0.5000 0.5062 0.5625 0.5676 0.645 0.6650 0.5000 5/8-8 ACME 0.625 8 5G 0.5000 0.5062 0.5625 0.5666 0.645 0.6650 0.5000 3/4-6 ACME 0.75 6 2G 0.5833 0.5916 0.6667 0.6841 0.77 0.7900 0.5833 3/4-6 ACME 0.75 6 3G 0.5833 0.5916 0.6667 0.6748 0.77 0.7900 0.5833 3/4-6 ACME 0.75 6 4G 0.5833 0.5916 0.6667 0.6725 0.77 0.7900 0.5833 3/4-6 ACME 0.75 6 5G 0.5833 0.5916 0.6667 0.6714 0.77 0.7900 0.5833 7/8-6 ACME 0.875 6 2G 0.7083 0.7166 0.7917 0.8096 0.895 0.9150 0.7083 7/8-6 ACME 0.875 6 3G 0.7083 0.7166 0.7917 0.8000 0.895 0.9150 0.7083 7/8-6 ACME 0.875 6 4G 0.7083 0.7166 0.7917 0.7977 0.895 0.9150 0.7083 7/8-6 ACME 0.875 6 5G 0.7083 0.7166 0.7917 0.7965 0.895 0.9150 0.7083 1-5 ACME 1 5 2G 0.8000 0.8100 0.9000 0.9194 1.02 1.0400 0.8000 1-5 ACME 1 5 3G 0.8000 0.8100 0.9000 0.9091 1.02 1.0400 0.8000 1-5 ACME 1 5 4G 0.8000 0.8100 0.9000 0.9065 1.02 1.0400 0.8000 1-5 ACME 1 5 5G 0.8000 0.8100 0.9000 0.9052 1.02 1.0400 0.8000 1 1/8-5 ACME 1.125 5 2G 0.9250 0.9350 1.0250 1.0448 1.145 1.165 0.9250 1 1/8-5 ACME 1.125 5 3G 0.9250 0.9350 1.0250 1.0342 1.145 1.165 0.9250 1 1/8-5 ACME 1.125 5 4G 0.9250 0.9350 1.0250 1.0316 1.145 1.165 0.9250 1 1/8-5 ACME 1.125 5 5G 0.9250 0.9350 1.0250 1.0303 1.145 1.165 0.9250 1 1/4-5 ACME 1.25 5 2G 1.0500 1.0600 1.1500 1.1701 1.27 1.29 1.0500 1 1/4-5 ACME 1.25 5 3G 1.0500 1.0600 1.1500 1.1594 1.27 1.29 1.0500 1 1/4-5 ACME 1.25 5 4G 1.0500 1.0600 1.1500 1.1567 1.27 1.29 1.0500 1 1/4-5 ACME 1.25 4 5G 1.0500 1.0600 1.1500 1.1554 1.27 1.29 1.0500 1 3/8-4 ACME 1.375 4 2G 1.1250 1.1375 1.2500 1.2720 1.395 1.415 1.1250 1 3/8-4 ACME 1.375 4 3G 1.1250 1.1375 1.2500 1.2603 1.395 1.415 1.1250 1 3/8-4 ACME 1.375 4 4G 1.1250 1.1375 1.2500 1.2573 1.395 1.415 1.1250 1 3/8-4 ACME 1.375 4 5G 1.1250 1.1375 1.2500 1.2559 1.395 1.415 1.1250 1 1/2-4 ACME 1.5 4 2G 1.2500 1.2625 1.3750 1.3973 1.52 1.54 1.2500 1 1/2-4 ACME 1.5 4 3G 1.2500 1.2625 1.3750 1.3854 1.52 1.54 1.2500 1 1/2-4 ACME 1.5 4 4G 1.2500 1.2625 1.3750 1.3824 1.52 1.54 1.2500 1 1/2-4 ACME 1.5 4 5G 1.2500 1.2625 1.3750 1.3810 1.52 1.54 1.2500 1 3/4-4 ACME 1.75 4 2G 1.5000 1.5125 1.6250 1.6479 1.77 1.79 1.5000 1 3/4-4 ACME 1.75 4 3G 1.5000 1.5125 1.6250 1.6357 1.77 1.79 1.5000 1 3/4-4 ACME 1.75 4 4G 1.5000 1.5125 1.6250 1.6326 1.77 1.79 1.5000 1 3/4-4 ACME 1.75 4 5G 1.5000 1.5125 1.6250 1.6311 1.77 1.79 1.5000 2-4 ACME 2 4 2G 1.7500 1.7625 1.8750 1.8985 2.02 2.04 1.7500 2-4 ACME 2 4 3G 1.7500 1.7625 1.8750 1.8860 2.02 2.04 1.7500 2-4 ACME 2 4 4G 1.7500 1.7625 1.8750 1.8828 2.02 2.04 1.7500 2-4 ACME 2 4 5G 1.7500 1.7625 1.8750 1.8813 2.02 2.04 1.7500 2 1/4-3 ACME 2.25 3 2G 1.9167 1.9334 2.0833 2.1096 2.27 2.29 1.9167 2 1/4-3 ACME 2.25 3 3G 1.9167 1.9334 2.0833 2.0956 2.27 2.29 1.9167 2 1/4-3 ACME 2.25 3 4G 1.9167 1.9334 2.0833 2.0921 2.27 2.29 1.9167 2 1/4-3 ACME 2.25 3 5G 1.9167 1.9334 2.0833 2.0903 2.27 2.29 1.9167 2 1/2-3 ACME 2.5 3 2G 2.1667 2.1834 2.3333 2.3601 2.52 2.54 2.1667 2 1/2-3 ACME 2.5 3 3G 2.1667 2.1834 2.3333 2.3458 2.52 2.54 2.1667 2 1/2-3 ACME 2.5 3 4G 2.1667 2.1834 2.3333 2.3422 2.52 2.54 2.1667 2 1/2-3 ACME 2.5 3 5G 2.1667 2.1834 2.3333 2.3404 2.52 2.54 2.1667 2 3/4-3 ACME 2.75 3 2G 2.4169 2.4334 2.5833 2.6106 2.77 2.79 2.4169 2 3/4-3 ACME 2.75 3 3G 2.4169 2.4334 2.5833 2.5960 2.77 2.79 2.4169 2 3/4-3 ACME 2.75 3 4G 2.4169 2.4334 2.5833 2.5924 2.77 2.79 2.4169 2 3/4-3 ACME 2.75 3 5G 2.4169 2.4334 2.5833 2.5906 2.77 2.79 2.4169 3-2 ACME 3 2 2G 2.5000 2.5250 2.7500 2.7816 3.02 3.04 2.5000 3-2 ACME 3 2 3G 2.5000 2.5250 2.7500 2.7647 3.02 3.04 2.5000 3-2 ACME 3 2 4G 2.5000 2.5250 2.7500 2.7605 3.02 3.04 2.5000 3-2 ACME 3 2 5G 2.5000 2.5250 2.7500 2.7584 3.02 3.04 2.5000 3 1/2-2 ACME 3.5 2 2G 3.0000 3.0250 3.2500 3.2824 3.52 3.54 3.0000 3 1/2-2 ACME 3.5 2 3G 3.0000 3.0250 3.2500 3.2651 3.52 3.54 3.0000 3 1/2-2 ACME 3.5 2 4G 3.0000 3.0250 3.2500 3.2608 3.52 3.54 3.0000 3 1/2-2 ACME 3.5 2 5G 3.0000 3.0250 3.2500 3.2587 3.52 3.54 3.0000 4-2 ACME 4 2 2G 3.5000 3.5250 3.7500 3.7832 4.02 4.04 3.5000 4-2 ACME 4 2 3G 3.5000 3.5250 3.7500 3.7655 4.02 4.04 3.5000 4-2 ACME 4 2 4G 3.5000 3.5250 3.7500 3.7611 4.02 4.04 3.5000 4-2 ACME 4 2 5G 3.5000 3.5250 3.7500 3.7589 4.02 4.04 3.5000 4 1/2-2 ACME 4.5 2 2G 4.0000 4.0250 4.2500 4.2839 4.52 4.54 4.0000 4 1/2-2 ACME 4.5 2 3G 4.0000 4.0250 4.2500 4.2658 4.52 4.54 4.0000 4 1/2-2 ACME 4.5 2 4G 4.0000 4.0250 4.2500 4.2613 4.52 4.54 4.0000 4 1/2-2 ACME 4.5 2 5G 4.0000 4.0250 4.2500 4.2591 4.52 4.54 4.0000 5-2 ACME 5 2 2G 4.5000 4.5250 4.7500 4.7846 5.02 5.04 4.5000 5-2 ACME 5 2 3G 4.5000 4.5250 4.7500 4.7662 5.02 5.04 4.5000 5-2 ACME 5 2 4G 4.5000 4.5250 4.7500 4.7615 5.02 5.04 4.5000 5-2 ACME 5 2 5G 4.5000 4.5250 4.7500 4.7592 5.02 5.04 4.5000

The following table defines recommended industry standard sizes for External ACME General Purpose Threads per American National Standard ASME/ANSI B1.5. There are three classes of General Purpose ACME threads, 2G, 3G, and 4G each class provides some clearance on all standard size diameters for free movement, and are used in assemblies with the internal thread rigidly fixed and movement of the external thread in a direction perpendicular to its axis limited by its bearing or bearings. Designs should only utilize external and internal ACME threads of the same class and type, with Class 2G being the preferred choice. If less backlash or end play is desired, Classes 3G and 4G are provided. Class 5G is not recommended for new designs. Designation Size Decimal TPI Tol. Class Major Dia. Pitch Dia. Minor Dia. Max. Min. Max. Min. Max Min. 1/4-16 Acme 0.25 16 2G 0.2500 0.2450 0.2148 0.2043 0.1775 0.1618 1/4-16 Acme 0.25 16 3G 0.2500 0.2450 0.2158 0.2109 0.1775 0.1702 1/4-16 Acme 0.25 16 4G 0.2500 0.2450 0.2168 0.2133 0.1775 0.1722 1/4-16 Acme 0.25 16 5G 0.2500 0.2450 0.2188 0.2160 0.1775 0.1733 5/16-14 Acme 0.3125 14 2G 0.3125 0.3075 0.2728 0.2614 0.2311 0.2140 5/16-14 Acme 0.3125 14 3G 0.3125 0.3075 0.2738 0.2685 0.2311 0.2231 5/16-14 Acme 0.3125 14 4G 0.3125 0.3075 0.2748 0.271 0.2311 0.2254 5/16-14 Acme 0.3125 14 5G 0.3125 0.3075 0.2768 0.2738 0.2311 0.2266 3/8-12 Acme 0.375 12 2G 0.3750 0.3700 0.3284 0.3161 0.2817 0.2632 3/8-12 Acme 0.375 12 3G 0.3750 0.3700 0.3296 0.3238 0.2817 0.2730 3/8-12 Acme 0.375 12 4G 0.3750 0.3700 0.3309 0.3268 0.2817 0.2755 3/8-12 Acme 0.375 12 5G 0.3750 0.3700 0.3333 0.33 0.2817 0.2767 7/16-12 Acme 0.4375 12 2G 0.4375 0.4325 0.3909 0.3783 0.3442 0.3253 7/16-12 Acme 0.4375 12 3G 0.4375 0.4325 0.3921 0.3862 0.3442 0.3354 7/16-12 Acme 0.4375 12 4G 0.4375 0.4325 0.3934 0.3892 0.3442 0.3379 7/16-12 Acme 0.4375 12 5G 0.4375 0.4325 0.3958 0.3924 0.3442 0.3391 1/2-10 Acme 0.5 10 2G 0.5000 0.4950 0.4443 0.4306 0.3800 0.3594 1/2-10 Acme 0.5 10 3G 0.5000 0.4950 0.4458 0.4394 0.3800 0.3704 1/2-10 Acme 0.5 10 4G 0.5000 0.4950 0.4472 0.4426 0.3800 0.3731 1/2-10 Acme 0.5 10 5G 0.5000 0.4950 0.45 0.4463 0.3800 0.3745 5/8-8 Acme 0.625 8 2G 0.6250 0.6188 0.5562 0.5408 0.4800 0.4569 5/8-8 Acme 0.625 8 3G 0.6250 0.6188 0.5578 0.5506 0.4800 0.4692 5/8-8 Acme 0.625 8 4G 0.6250 0.6188 0.5593 0.5542 0.4800 0.4723 5/8-8 Acme 0.625 8 5G 0.6250 0.6188 0.5625 0.5584 0.4800 0.4738 3/4-6 Acme 0.75 6 2G 0.7500 0.7417 0.6598 0.6424 0.5633 0.5372 3/4-6 Acme 0.75 6 3G 0.7500 0.7417 0.6615 0.6534 0.5633 0.5511 3/4-6 Acme 0.75 6 4G 0.7500 0.7417 0.6632 0.6574 0.5633 0.5546 3/4-6 Acme 0.75 6 5G 0.7500 0.7417 0.6667 0.662 0.5633 0.5563 7/8-6 Acme 0.875 6 2G 0.8750 0.8667 0.7842 0.7663 0.6883 0.6615 7/8-6 Acme 0.875 6 3G 0.8750 0.8667 0.7861 0.7778 0.6883 0.6758 7/8-6 Acme 0.875 6 4G 0.8750 0.8667 0.788 0.782 0.6883 0.6794 7/8-6 Acme 0.875 6 5G 0.8750 0.8667 0.7917 0.7869 0.6883 0.6811 1-5 Acme 1 5 2G 1.0000 0.9900 0.892 0.8726 0.7800 0.7509 1-5 Acme 1 5 3G 1.0000 0.9900 0.894 0.8849 0.7800 0.7664 1-5 Acme 1 5 4G 1.0000 0.9900 0.896 0.8895 0.7800 0.7703 1-5 Acme 1 5 5G 1.0000 0.9900 0.9 0.8948 0.7800 0.7722 1 1/8-5 Acme 1.125 5 2G 1.1250 1.1150 1.0165 0.9967 0.9050 0.8753 1 1/8-5 Acme 1.125 5 3G 1.1250 1.1150 1.0186 1.0094 0.9050 0.8912 1 1/8-5 Acme 1.125 5 4G 1.1250 1.1150 1.0208 1.0142 0.9050 0.8951 1 1/8-5 Acme 1.125 5 5G 1.1250 1.1150 1.025 1.0197 0.9050 0.8971 1 1/4-5 Acme 1.25 5 2G 1.2500 1.2400 1.1411 1.121 1.0300 0.9998 1 1/4-5 Acme 1.25 5 3G 1.2500 1.2400 1.1433 1.1339 1.0300 1.0159 1 1/4-5 Acme 1.25 5 4G 1.2500 1.2400 1.1455 1.1388 1.0300 1.0199 1 1/4-5 Acme 1.25 4 5G 1.2500 1.2400 1.15 1.1446 1.0300 1.0219 1 3/8-4 Acme 1.375 4 2G 1.3750 1.3625 1.2406 1.2188 1.1050 1.0720 1 3/8-4 Acme 1.375 4 3G 1.3750 1.3625 1.243 1.2327 1.1050 1.0896 1 3/8-4 Acme 1.375 4 4G 1.3750 1.3625 1.2453 1.238 1.1050 1.0940 1 3/8-4 Acme 1.375 4 5G 1.3750 1.3625 1.25 1.2441 1.1050 1.0962 1 1/2-4 Acme 1.5 4 2G 1.5000 1.4875 1.3652 1.3429 1.2300 1.1965 1 1/2-4 Acme 1.5 4 3G 1.5000 1.4875 1.3677 1.3573 1.2300 1.2144 1 1/2-4 Acme 1.5 4 4G 1.5000 1.4875 1.3701 1.3627 1.2300 1.2189 1 1/2-4 Acme 1.5 4 5G 1.5000 1.4875 1.375 1.369 1.2300 1.2210 1 3/4-4 Acme 1.75 4 2G 1.7500 1.7375 1.6145 1.5916 1.4800 1.4456 1 3/4-4 Acme 1.75 4 3G 1.7500 1.7375 1.6171 1.6064 1.4800 1.4640 1 3/4-4 Acme 1.75 4 4G 1.7500 1.7375 1.6198 1.6122 1.4800 1.4686 1 3/4-4 Acme 1.75 4 5G 1.7500 1.7375 1.625 1.6189 1.4800 1.4708 2-4 Acme 2 4 2G 2.0000 1.9875 1.8637 1.8402 1.7300 1.6948 2-4 Acme 2 4 3G 2.0000 1.9875 1.8665 1.8555 1.7300 1.7135 2-4 Acme 2 4 4G 2.0000 1.9875 1.8693 1.8615 1.7300 1.7183 2-4 Acme 2 4 5G 2.0000 1.9875 1.875 1.8687 1.7300 1.7206 2 1/4-3 Acme 2.25 3 2G 2.2500 2.2333 2.0713 2.045 1.8967 1.8572 2 1/4-3 Acme 2.25 3 3G 2.2500 2.2333 2.0743 2.062 1.8967 1.8783 2 1/4-3 Acme 2.25 3 4G 2.2500 2.2333 2.0773 2.0685 1.8967 1.8835 2 1/4-3 Acme 2.25 3 5G 2.2500 2.2333 2.0833 2.0763 1.8967 1.8862 2 1/2-3 Acme 2.5 3 2G 2.5000 2.4833 2.3207 2.2939 2.1467 2.1065 2 1/2-3 Acme 2.5 3 3G 2.5000 2.4833 2.3238 2.3113 2.1467 2.1279 2 1/2-3 Acme 2.5 3 4G 2.5000 2.4833 2.327 2.3181 2.1467 2.1333 2 1/2-3 Acme 2.5 3 5G 2.5000 2.4833 2.333 2.3262 2.1467 2.1360 2 3/4-3 Acme 2.75 3 2G 2.7500 2.7333 2.57 2.5427 2.3967 2.3558 2 3/4-3 Acme 2.75 3 3G 2.7500 2.7333 2.5734 2.567 2.3967 2.3776 2 3/4-3 Acme 2.75 3 4G 2.7500 2.7333 2.5767 2.5676 2.3967 2.3831 2 3/4-3 Acme 2.75 3 5G 2.7500 2.7333 2.5833 2.576 2.3967 2.3858 3-2 Acme 3 2 2G 3.0000 2.9750 2.736 2.7044 2.4800 2.4326 3-2 Acme 3 2 3G 3.0000 2.9750 2.7395 2.7248 2.4800 2.4579 3-2 Acme 3 2 4G 3.0000 2.9750 2.743 2.7325 2.4800 2.4642 3-2 Acme 3 2 5G 3.0000 2.9750 2.75 2.7416 2.4800 2.4674 3 1/2-2 Acme 3.5 2 2G 3.5000 3.4750 3.235 3.2026 2.9800 2.9314 3 1/2-2 Acme 3.5 2 3G 3.5000 3.4750 3.2388 3.2237 2.9800 2.9574 3 1/2-2 Acme 3.5 2 4G 3.5000 3.4750 3.2425 3.2317 2.9800 2.9638 3 1/2-2 Acme 3.5 2 5G 3.5000 3.4750 3.25 3.2413 2.9800 2.9669 4-2 Acme 4 2 2G 4.0000 3.9750 3.734 3.7008 3.4800 3.4302 4-2 Acme 4 2 3G 4.0000 3.9750 3.738 3.7225 3.4800 3.4568 4-2 Acme 4 2 4G 4.0000 3.9750 3.742 3.7309 3.4800 3.4634 4-2 Acme 4 2 5G 4.0000 3.9750 3.75 3.7411 3.4800 3.4666 4 1/2-2 Acme 4.5 2 2G 4.5000 4.4750 4.233 4.1991 3.9800 3.9291 4 1/2-2 Acme 4.5 2 3G 4.5000 4.4750 4.2373 4.2215 3.9800 3.9563 4 1/2-2 Acme 4.5 2 4G 4.5000 4.4750 4.2415 4.2302 3.9800 3.9631 4 1/2-2 Acme 4.5 2 5G 4.5000 4.4750 4.25 4.2409 3.9800 3.9663 5-2 Acme 5 2 2G 5.0000 4.9750 4.7319 4.6973 4.4800 4.4281 5-2 Acme 5 2 3G 5.0000 4.9750 4.7364 4.7202 4.4800 4.4557 5-2 Acme 5 2 4G 5.0000 4.9750 4.7409 4.7294 4.4800 4.4627 5-2 Acme 5 2 5G 5.0000 4.9750 4.75 4.7408 4.4800 4.4662

National Standard Taper Pipe Threads Size NPT Chart - Includes both External and internal Pipe Thread Data. The taper rate for all NPT threads is 1⁄16 (3⁄4 inch per foot) measured by the change of diameter (of the pipe thread) over distance. The angle between the taper and the center axis of the pipe is 1° 47'′ 24"″ (1.7899°). Commonly-used sizes are 1/⁄8, 1/⁄4, 3/⁄8, 1⁄/2, 3⁄/4, 1, 1 1⁄/4, 1 1⁄/2, and 2 inch, appearing on pipes and fittings by most U.S. suppliers. Sizes smaller than 1/⁄8 inch are occasionally used for compressed air, while sizes larger than 2 inches are uncommon, due to the use of alternative methods of joining that are used with these larger sizes. NPT is defined by ANSI/ASME standard B1.20.1. Nominal Pipe Size is loosely related to the inside diameter of Schedule 40 pipe. Because of the pipe wall thickness, the actual diameter of the threads is larger than the NPS, considerably so for small NPS. Other schedules of pipe have different wall thickness but the OD (outer diameter) and thread profile remain the same, so the inside diameter of the pipe is therefore different from the nominal diameter. Notes:   Reference ANSI/ASME B1.20.1-1983 (R1992) Angle between sides of thread is 60 degrees. Thread taper, is 3⁄4 inch per foot. All units are in inches. Outside Diameter Nominal Pipe Size Thread per Inch (Pitch) Thread Pitch Length, P Pitch Diameter at External Thread Start E0 Hand Tight Thread Engagement Length, L1 Diameter E1 Maximum Thread Engagement L2 Diameter E2 0.3125 1/16 27 0.03704 0.27118 0.160 0.28118 0.2611 0.28750 0.405 1/8 27 0.03704 0.36351 0.1615 0.37360 0.2639 0.38000 0.540 ¼ 18 0.05556 0.47739 0.2278 0.49163 0.4018 0.50250 0.675 3/5 18 0.05556 0.61201 0.240 0.62701 0.4078 0.63750 0.840 ½ 14 0.07143 0.75843 0.320 0.77843 0.5337 0.79179 1.050 ¾ 14 0.07143 0.96768 0.339 0.98887 0.5457 1.00179 1.315 1 11 ½ 0.08696 1.21363 0.400 1.23863 0.6828 1.25630 1.660 1 ¼ 11 ½ 0.08696 1.55713 0.420 1.58338 0.7068 1.60130 1.900 1 ½ 11 ½ 0.08696 1.79609 0.420 1.82234 0.7235 1.84130 2.375 20 11 ½ 0.08696 2.26902 0.436 2.29627 0.7565 2.31630 2.875 2 ½ 8 0.08696 2.71953 0.682 2.76216 1.1375 2.79062 3.500 3/5 8 0.12500 3.34062 0.766 3.38850 1.2000 3.41562 4.000 3 ½ 8 0.12500 3.83750 0.821 3.8881 1.2500 3.91562 4.500 4 8 0.12500 4.33438 0.844 4.38712 1.3000 4.41562 5.563 5 8 0.12500 5.39073 0.937 5.44929 1.4063 5.47862 6.625 6 8 0.12500 6.44609 0.958 6.50597 1.5125 6.54062 8.625 8 8 0.12500 8.43359 1.063 8.50003 1.7125 8.54062 10.750 10 8 0.12500 10.54531 1.210 10.62094 1.9250 10.66562 12.750 12 8 0.12500 12.53281 1.360 12.61781 2.1250 12.66562 14.000 14 8 0.12500 13.77500 1.562 13.87262 2.2500 13.91562 16.000 16 8 0.12500 15.76250 1.812 15.87575 2.4500 15.91562 18.000 18 8 0.12500 17.75000 2.000 17.87500 2.6500 17.91562 20.000 20 8 0.12500 19.73750 2.125 19.87031 2.8500 19.91562 24.000 24 8 0.12500 23.71250 2.375 23.86094 3.2500 32.91562 National Standard Taper Pipe Threads Size NPT Chart

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MACHINERY'S HANDBOOK, Toolbox Edition  MACHINERY'S HANDBOOK, Larger Print   INTRODUCTION TO MEASURATION AND CALIBRATION  BLUEPRINT READING BASICS  GUIDE TO WORLD SCREW THREADS  INTERPRETATION OF GEOMETRIC DIMENSIONING AND TOLERANCING  HANDBOOK OF DIMENSIONAL MEASUREMENT INSPECTION AND GAGING View WESTports large selection of Gages at the guaranteed lowest price MACHINERY'S HANDBOOK, 26th Edition, Toolbox Edition Oberg, Jones, Horton, Ryffel, McCauley, Heald and Hussain 2000 2640 pp Illustrated 0-8311-2625-6 After more than 85 years of continuous publication, Machinery’s Handbook remains unchallenged as "The Bible" in its field, and the new 26th edition remains true to the Handbook’s original design as an extraordinarily comprehensive yet practical and easy. Nearly 100 pages longer overall than prior editions. An expanded table of contents and index to make finding Mathematics. Mechanics. Strength of Materials. Properties, Treatment, and Testing of Materials.Plastics. Dimensioning, Gaging, & Measuring. Tooling and Toolmaking. Machining Operations. Manufacturing Processes. Fasteners. Thread Gages & Threading. Gears,Industrial Press, Inc. MACHINERY'S HANDBOOK, 26th Edition, Larger Print  Edition Oberg, Jones, Horton, Ryffel, McCauley, Heald and Hussain. 2000 2640 pp Illustrated 0-8311-2635-3 After more than 85 years of continuous publication, the Machinery's Handbook remains unchallenged as "The Bible" in its field, and the new 26th edition remains true to the Handbook's original design as a comprehensive yet practical and easy to read. Nearly 100 pages longer than prior editions. An expanded table of contents and index to make finding Mathematics. Mechanics. Strength of Materials. Properties, Treatment, and Testing of Materials. Plastics. Dimensioning, Gaging, and Measuring. Tooling and Toolmaking. Machining Operations. Manufacturing Processes. Fasteners. Thread Gages & Threading Gears, Industrial Press, Inc. INTRODUCTION TO MEASURATION AND CALIBRATION Paul Campbell 1995 208 pp Illustrated 0-8311-3060- 1 Provides illustrations of the devices throughout with descriptions of how they are used in industry. Offers a vast amount of new material that can be applied to virtually any imaginable measurement or calibration task. Measuration Systems. Mechanical Measuring Devices. Squares and Surface Plate Instruments. Gages. Angular Measuring Devices. Electronic Measuring Devices. Optical Measuring Devices. Miscellaneous Measuring Devices. Appendices. Metric/English Conversions, Industrial Press, Inc. BLUEPRINT READING BASICS   Warren Hammer 1996 320 pp Illustrated 0-8311-3062-8 The new second edition of this widely used text and self-training manual has been expanded to include many new worksheets designed to facilitate the reader's ability to form a mental picture from a drawing. Written in a non-technical and easy to understand manner that is appropriate for machinists, mechanics, technicians, and inspectors, as well as students taking blueprint reading, engineering. The Basics of Blueprints. The Reading of Blueprints. The Lines and Views of Blueprints. The Total Blueprint. Dimensions. Tolerances. Surface Texture. Threads. Fasteners. Gears. Machine Terms and Holes. Machining Requirements. Geometric Dimensioning & Tolerances. Industrial Press, Inc.  GUIDE TO WORLD SCREW THREADS P. A. Sidders 1969 318 Illustrated 0-8311-1092-9 Provides encyclopedic coverage of the different types of threads standardized throughout the world. Includes Unified & American thread series; American translational and American thread pipe gages; British thread gages of Whitworth and non-Whitworth forms; ISO. British thread gages of Whitworth Form. British thread gages of Non-Whitworth Form. Unified and American Series. American Translational Threads. American Pipe Thread gages. A.P.I. Casing & Standard Tubing. Continental Forms and Series. Hotological Screws. Industrial Press, Inc. INTERPRETATION OF GEOMETRIC DIMENSIONING AND TOLERANCING, Second Edition Daniel E. Puncochar 1997 160 Illustrated 0-8311-3072-5 Geometric dimensioning and tolerancing (GD&T) is accepted around the world as the international symbolic language that allows engineers & machinists to use engineering drawings to communicate from the design stage through manufacturing and inspection. Uses "building-block" approach with examples (dimensioned and toleranced in inches and millimeters) to illustrate each concept. Reinforces the explanations with end-of-chapter self evaluation exercises (answers to all questions and problems) Symbols & Abbreviations. Datums. Feature Control Frames. General Rules. Form and Orientation Tolerances. Virtual Condition. Tolerances of Location. Practical Applications. Appendices: Past Practices, Plus/Minus Positional Tolerancing, Symb. Industrial Press, Inc. HANDBOOK OF DIMENSIONAL MEASUREMENT Nineteen Fact-Filled Charters that contain authoritative treatment of all aspects of dimensional measurement technology make Handbook of Dimensional Measurement the most readable and comprehensive guide available for engineers and technicians engages in the various stages of industrial production. Design engineers, manufacturing engineers, tool and gage makers, quality control specialists, and reliability experts will find a wealth of practical data as well as complete coverage - both basic and advanced - of dimensional measurement techniques and equipment. The Third Edition of this classic book has been completely revised to include the computer and electronics revolution in metrology. Virtually every type of measurement instrument and machine, even the newest devices, can be found in these pages. Hundreds of changes, and additions and scores of new illustrations have been incorporated to assure that Handbook of Dimensional Measurement retains its status as the standard reference for the practitioner of dimensional measurement. INSPECTION AND GAGING, Sixth Edition Clifford W. Kennedy, Edward G. Hoffman, and Steven D. Bond. 1987 654 pp. Illustrated. 0-8311-1149-6. Highly acclaimed training manual and reference discusses a range of manual and automatic measuring devices along with their specific functions and the specialized functions involved in their use. Analyzes the methods and duties of inspectors. Ideal for use by inspection supervisors, and plant managers. The Need and Function of Inspection in Industry. How Specifications Aid the Inspector. Tolerances and Allowances. How Standards Aid the Inspection. Basic Principles and Techniques of Measurement. Comparison & Fixed Limit Gages. Surface Plate Methods & Equip. Industrial Press, Inc.