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Threaded Cap — OEM manufacturer, Teshi Group

OEM manufacturer ASME B16.11 · ASME B1.20.1

Threaded Caps — ASME B16.11

A threaded cap screws onto the male-threaded end of a pipe or nipple to close it. Teshi Group manufactures threaded caps to ASME B16.11 in Class 3000 and 6000, with NPT threads to ASME B1.20.1.

Also called: screwed cap, NPT cap, forged threaded end cap, female threaded cap, pipe cap threaded

StandardASME B16.11
Pressure classClass 3000 and 6000
Size rangeNPS ⅛"–4" (DN 6–100) per ASME B16.11

What is a Threaded Cap?

A threaded cap is a forged fitting with a female thread and a closed end. It screws over a male pipe or nipple end and can be removed for draining, venting or extending the line. A plug does the same job for a female-threaded opening. Caps are used on drains, vents, test points and spare connections in small-bore piping. Caps are ordered by size, class and material to match the pipe.

Key features

  • Forged body per ASME B16.11
  • Class 3000 and 6000
  • NPT female thread per ASME B1.20.1
  • Removable closure for male pipe ends

Specification

SupplyOEM manufacturer — Teshi Group, India, India
StandardASME B16.11
Pressure classClass 3000 and 6000
Pipe compatibilityClass 3000 → Sch 160, Class 6000 → XXS pipe
Size rangeNPS ⅛"–4" (DN 6–100) per ASME B16.11
ThreadsNPT per ASME B1.20.1; BSPT (ISO 7-1) on request
Materials — carbon & low-temp steelASTM A105; ASTM A350 LF2 Cl.1
Materials — alloy steelASTM A182 F11 Cl.2, F22 Cl.3, F5, F9, F91
Materials — stainless & duplexASTM A182 F304, F304L, F316, F316L, F321; F51, F53 duplex
TestingVisual, dimensional and thread/socket gauge inspection; PMI on alloy and stainless grades; hardness check; MPI/DPT when specified
DocumentsEN 10204 3.1 mill test certificate; 3.2 / third-party inspection when the order specifies; dimensional inspection report; IBR certification for boiler/steam service when specified

Applications

  • Drain and vent ends
  • Test and spare connections
  • Instrument line ends
  • Utility piping

Threaded cap vs threaded plug

A threaded cap has a female thread and closes a male-threaded pipe or nipple end. A threaded plug has a male thread and closes a female-threaded opening such as a tee outlet, coupling, threadolet or valve drain. Choose by the gender of the end that needs closing, and match the material and class to the piping specification. Both can be removed later for draining, venting or extending the line.

FAQ

Threaded Cap: common questions

What is the difference between a cap and a plug?

A cap has a female thread and screws onto a male pipe or nipple end. A plug has a male thread and screws into a female opening. Both are covered by ASME B16.11.

Which class should I order?

Match your piping specification. Class 3000 threaded caps are rated for use with Sch 160 pipe and Class 6000 caps with XXS pipe of equivalent material.

Can threaded caps be seal welded?

Yes, where the piping specification requires it. Seal welding should follow the piping code and a qualified welding procedure for that material, with thread compound kept off the weld area.

What documents are supplied?

An EN 10204 3.1 mill test certificate is supplied as standard. EN 10204 3.2 or third-party inspection, and IBR certification for boiler or steam service, are provided when the order specifies them.

Need a size or grade not listed here?

Our engineering team manufactures against your drawing or datasheet, with dimensional sign-off before dispatch.

Send us your specification

Traceability

From mill heat to your site

  1. 01

    Approved mill material

    Received against the mill certificate; heat number registered.

  2. 02

    Forging & machining

    Heat number carried through every stage in our Indian works.

  3. 03

    PMI, dimensional & NDT

    Every lot inspected to the governing standard; TPI witness on request.

  4. 04

    Stamped & certified dispatch

    Hard-stamped pieces with EN 10204 3.1 / 3.2 certificates.

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