Mining Casing

Before cutting a connection, making sure the threading insert in the machine is correct for the thread being produces is essential. Gagemaker’s JSS Thread Insert Identifier Template provides a quick and easy method for machinists to verify that the correct threading insert has been selected. JSS insert identifier templates have multiple notches that can be used to verify several different thread forms.

The JSS thread insert identifier allows quick and accurate identification of the threading insert before cutting connections.

• USS Improved Buttress Tubing
• Line Pipe
• Special Clearance Couplings
• SR13 Seal Ring Groove Couplings

TDWIN Taper is available in single and multi-user models. Multi-user models may be adjusted to a customer specific number. Contact customer service for more information.

System Requirements

• Microsoft Windows XP or newer
• USB 2.0 port
• Internet Connection for first use
• 1 MB RAM or more (recommended)
• Screen resolution of 1024 X 768 minimum
• .Net Framework 2.0 or later installed

Correct thread form is important for a pipe end and coupling to make up properly. Doing a quick check using a Gagemaker thread profile verifies the thread form is correct.

Profile gages can also be used to perform a visual inspection of a thread form for detecting chipped inserts, steps, flat crested threads, stretched threads, wide first threads, or rolled over threads.

Thread Form Profiles

Gagemaker manufactures precision tapered thread profile gages for the quick identification of product thread forms. Specify the connection which is to be inspected when ordering. Special profiles will be quoted upon request.

Overlay Charts are also available. For information, contact Gagemaker directly. Specials are also available. For Special Overlays, please specify the following:

1. Screen Size
2. Magnification 20X/50X
3. Product Form or Profile Template

Gagemaker lead gages use interchangeable contact points to inspect both pin and box threads for a wide variety of API tubing & casing connections. Lead inspection is both an API mandated requirement and an industry wide practice. Defined as the distance between threads as measured on a plane parallel to the centerline of the threaded part, lead variation has a direct effect on stand-off, thread flank engagement, and make-up. Lead error is most commonly generated by manual and CNC lathes not cutting properly. Gagemaker lead gages provide dimensional verification of product print data.

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Lead Gages

The lead gage inspects both internal and external thread leads using contact points that seat in the threads of a part. The pitch of the thread determines the diameter of the contact points required for taking measurements.

The LG-6001 and the LG-6002 use a two-point system to inspect thread lead for straight and tapered threads. The LG-6002 inspects both external and internal threads, while the LG-6001 inspects external threads. The two point system allows for a sweeping action to obtain the measurement. Both gages are available with higher resolution indicators.

The LG-5003 is a three-point gage for inspecting thread lead on API threads. Two fixed contact points at the rear of the gage and one moveable contact point at the front of the gage provide complete stability when taking thread lead measurements. This unique design does not require sweeping to obtain measurements.

Contact points can be easily changed to allow the gages to be used on a variety of thread forms. See the contact tab to find your points.

Before inspecting parts, the lead gage must be preset to a nominal predetermined dimension using a lead gage setting standard. Find your lead standard on the setting tab.

Higher resolution and metric indicators are available. More gage models and accessories can be found on our lead gage product page.

	Model	Thread Length Range	Description	External/Internal	Number of Contact Points	Minimum Bore	Indicator Travel	Indicator Resolution	Contact Point Spacing
	LG-6001	½” – 2” (12.7 mm – 50.8 mm)	2-point external lead gage	External	2	2.750”	.100"	.0005”	.200”
	LG-6002	½” – 4” (0 mm – 101.6 mm)	2-point internal lead gage	Internal	2	1.450”	.100"	.0005”	.200”
	LG-5003	½” – 4” (0 mm – 101.6 mm)	3-point external/internal lead gage	External/Internal	3	1.340”	.100"	.0005”	.500”

Lead Gage Setting Standard

Gagemaker’s precision lead gage setting standards are manufactured in accordance with API Specification 5B. Lead gage standards are used to set the gage prior to the inspection.

*Line Pipe and NPT contact points and standards are available.
For more lead gage options, contact points, and standards, see our lead gage product page.

API Contact Points for Lead Gages

Gagemaker’s standard ball contact points are manufactured with carbide balls. Both threaded and straight (non-threaded) shanks are available. All of Gagemaker’s inspection gages use threaded shank contact points and are #4-48 UNF. Metric threads are available upon request. Lead gages require two or three contact points. Contact points are sold individually.

*Line Pipe and NPT contact points and standards are available.
For more lead gage options, contact points, and standards, see our lead gage product page.

Crest diameter and ovality are one of the most critical measurements of thread inspection governing the strength of the actual thread assembly.  The Gagemaker MRP® crest diameter ages measure the external and internal pitch diameters of tapered threaded connectors, primarily tubing and casing connections.  Any slight variations in diameter are immediately detected with these precision gages granting you total control over your quality.

These versatile gages easily adjust to measure thread diameters ranging from 1½” – 24”. The ability to inspect a range of diameters with one gage, eliminates the need for a room full of ring or plug gages.

MRP® Crest Diameter and Ovality Inspection

The MRP® crest diameter and ovality gages detect variations in crest diameter by the use of a gage shoe that rests on the crest of the threads. Variation in diameter is detected by the indicator readout. These gages must be set to a nominal size with a setting standard or a MIC TRAC™. Refer to the standard chart that follows. All of these gages are API approved for use on tubing and casing. Parts and accessories can be found on our crest diameter product page.

Casing Connections Rod & Frame Standards

Step style standards are also available. Please see our MRP product page for more information.

Tapered threads are a signature feature of API Tubing & Casing connections. Measuring thread taper is not only an industry wide practice, it is an API Specification 5B mandated inspection. During the manufacturing process, taper must be accurately measured and quantified to stay within the required specification limits. When subjected to a service load, taper error on threaded tubing and casing connections can lead to galling, improper fit, and reduced performance.

For the most accurate taper inspection, use Gagemaker taper gages to verify both the threaded pin and coupling meet all customer and industry requirements. Gagemaker’s taper gages are the best choice for measuring and controlling both pin and box taper values.

External Taper

Gagemaker’s external taper gages inspect variation in external thread taper. Unless specified otherwise, external taper gages are shipped with .072” diameter contact points (T072) as standard. Refer to the chart on the following page for the proper contact point for your particular connection. Each gage requires two contact points. Higher resolution indicators are available.

Internal Taper

Gagemaker’s internal taper gages measure variation in thread taper. Taper gages are shipped with our standard set of .072” diameter contact points (T072), unless specified otherwise or requested. Refer to the chart on the following page for the proper contact point for your particular connection. Each internal gage requires two contact points. Higher resolution indicators are available.

API Contact Points for Taper Gages

Gagemaker’s standard ball contact points are manufactured with carbide balls. All of Gagemaker’s inspection gages use threaded shank contact points. Threaded shanks are #4-48 UNF. Metric threads are available upon request. Taper gages require two contact points. Additional contact points can be found on pages 124-125.

Proper Thread Height maximizes the performance of the connection.  Thread height inspection is an API requirement.  Gagemaker thread height gages inspect external or internal thread height for a variety of thread forms.  A shallow thread height may allow the connection to pull apart under stress.

External Thread Height

Gagemaker manufactures many models of external thread height gages. Specify the type of thread when ordering. One contact point based on thread type is included, please refer to the chart on page 35. Standards may be required, please see the Setting tab for options. Metric and higher resolution indicators are also available, see our thread height gage product page for more options.

Internal Thread Height

Gagemaker also manufactures several models of internal thread height gages. Please specify the type of thread when ordering. One contact point based on thread type is included. Standards may be required, please see the Setting tab for options. Metric and higher resolution indicators are also available, see our thread height gage product page for more options.

External Thread Shave/Addendum

Thread Addendum (or previously known as Thread Shave) is simply the distance from the thread crest to the pitch line. The addendum is a shorter distance than the thread height. Addendum is typically only measured and controlled on tubing and casing 60° V threads (8 Round, 10 Round, and Line Pipe). For more info, read our May 2013 newsletter article on thread addendum.
Gagemaker manufactures many models of external thread height gages

Thread Height Gage Standards

Gagemaker manufactures API mandated precision setting standards for presetting thread height gages. Please specify the type of thread when ordering.

Thread Height Gage Contact Points

The contact points are interchangeable between gages. Contact point diameters are manufactured to tolerances of +.0002”. Thread height gages require one contact point. Additional contact points for threads not listed may be viewed on our contact points page.