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JSS Tubing and Casing Inspection

Tubing & Casing JSS® Thread Inspection System

Thread Check Inc. offers Gagemaker’s JSS® Tubing & Casing Thread Inspection System which takes the guesswork out of inspecting tubing  and casing. The Gagemaker Tubing & Casing Thread Inspection system inspects all required thread elements – Insert Identification, Thread Form, Crest Diameter & Ovality, Thread Lead, Thread Height, and Thread Taper – all with the precise accuracy required in today’s demanding industry.

  • Optimize performance for tubing and casing.
  • Extend longevity of tubing and casing.
  • Scrutinize all thread elements with greater precision and accuracy.
  • Inspect all types of tubing and casing connectors including API round thread, long thread, short thread, line pipe, and buttress.
  • Protect against mechanical forces such as tension and leakage that tend to destroy tubing & casing connection.
  • Inspect both standard and non-standard connections – all using the same gages.
  • Ensure proper thread interference with pipe and coupling make-up.
  • Pinpoint thread errors that cause expansion of the coupling and compression of the pipe end



Insert Identifiers

The first step in the quality process is to ensure the threading insert being used is correct for the job.
Use the JSS™ Thread Insert Identifier Template to quickly verify that the correct threading insert has been selected as well as check the full topping profile of both internal and external inserts.



Inspection Setup

TDWIN Taper™ is the only software program dedicated to the manufacturing and inspection of downhole tubular connections. It has everything you need to machine, inspect, and document tubular connection threads. TDWIN Taper™ relies on API and industry standard tables and tolerances. TDWIN Taper™ displays connection drawings, inspection gage information, and setup and inspection reports. Simply, it is a must have for any machine shop.

Thread Form

Thread form accuracy is important if two connectors are to make-up properly. Using a JSS Thread Profile Gage and a JSS Thread Addendum Gage provide a quick check of the thread to ensure that the form is correct. Thread form verification ensures form accuracy. Also, checking thread form will ensure the first imperfect thread is fully deburred.
Thread form is defined as its profile in an axial plane for a length of one pitch. Most importantly, verifying thread form is a recommended inspection for API connections and ensures form accuracy.


Thread Lead Inspection

API Mandated Requirement

Thread Lead is one of the most important thread elements to monitor. Not only is lead inspection an industry wide practice for rotary shouldered connections, it is an API mandated requirement. Lead error is most commonly generated by manual and CNC lathes not cutting properly.

Verifying thread lead is within tolerance is a required inspection according to API specification. Application of a Gagemaker Lead Gage to a setting standard and then to the product confirms that the lathe is cutting properly. Lead variation has a direct effect on pitch diameter and how two connectors go together when made up.

Thread lead is the distance between threads, measured on a plane parallel to the centerline of the threaded part. Lead error has a direct effect on functional diameter, stand-off, and thread flank engagement.

Gagemaker’s lead gages inspect pin and box connections for multiple pitches and thread forms. The gages provide dimensional verification of product print data on the thread’s true integrity.

  • Interchangeable contact points allow inspection on a variety of thread forms and sizes.
  • Inspect RSC threads as well as Tubing and Casing threads
  • Requires presetting using Gagemaker’s lead gage setting standards.



Crest Diameter & Ovality Inspection

  • Thirty years ago, Gagemaker introduced the MRP® crest diameter and ovality gage which forever changed the industry. Today, the MRP® series of gages is the industry standard worldwide. Whether you call it Crest Diameter, Root Diameter, or Ball PD, Pitch Diameter governs the strength of the actual thread assembly and ensures API dimensional measurement specs are met. (Check out the new carbon fiber MRP AIR.)
  • The Gagemaker MRP® crest diameter gages measure the internal and external pitch diameters of tapered threaded connections. Any slight variations in diameter or ovality are immediately detected with these precision gages allowing the operator total control over the quality in the threads they are producing. MRP® crest diameter gages are extremely versatile with 3 models that can easily adjust to measure thread diameters ranging from 1½” – 20”. The ability to inspect and measure a range of internal and external diameters with one gage, eliminates the need for heavy, cumbersome, and expensive fixed limit ring or plug gages.

Thread Taper Inspection

API Spec. 5B Mandated Inspection

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.



Thread Height Inspection

API Required Inspection

The correct thread height maximizes the performance of any threaded connection and is a required inspection by the API. Thread height affects both the interchangeability and integrity of a thread assembly. Thread height is the distance between the crest and the root, normal to the axis of the thread.

Gagemaker Thread Height Gages provide immediate feedback on how the thread height compares to the specification requirements. A shallow thread height may allow the connection to pull apart under critical loads.

Inspecting thread height can also help to detect a chipped tool. Gagemaker Thread Height Gages inspect both internal and external thread height for a variety of thread forms and provide immediate feedback on the integrity of your threads.