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Socket Weld Reducer Insert — OEM manufacturer, Teshi Group

OEM manufacturer MSS SP-79 · ASME B16.11

Socket Weld Reducer Inserts — MSS SP-79

A socket weld reducer insert fits into the socket of a standard socket weld fitting so that a smaller pipe can be connected. Teshi Group manufactures reducer inserts to MSS SP-79 in Class 3000 and 6000, in carbon, low-temperature, alloy and stainless steels.

Also called: reducing insert, SW reducer insert, socket weld reducing insert, MSS SP-79 insert

StandardMSS SP-79
Pressure classClass 3000 and 6000
Materials — carbon & low-temp steelASTM A105; ASTM A350 LF2 Cl.1

What is a Socket Weld Reducer Insert?

A reducer insert is a forged piece with a male spigot that goes into the socket of a tee, elbow or coupling, and a smaller socket that receives the reduced pipe. It turns a standard equal fitting into a reducing one, so a plant can stock fewer reducing fittings. MSS SP-79 covers socket welding reducer inserts, with socket dimensions consistent with ASME B16.11 fittings. Both the spigot and the smaller pipe are fillet welded.

Key features

  • Dimensions per MSS SP-79
  • Class 3000 and 6000
  • Converts equal SW tees, elbows and couplings into reducing fittings
  • Cuts inventory of reducing socket weld fittings

Specification

SupplyOEM manufacturer — Teshi Group, India, India
StandardMSS SP-79
Pressure classClass 3000 and 6000
Size rangeLarge-end and small-end combinations as tabulated in MSS SP-79
Pipe compatibilityClass 3000 → Sch 80, Class 6000 → Sch 160 pipe
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

  • Reduced branches from standard SW tees
  • Instrument and sampling connections
  • Drain and vent takeoffs
  • Small-bore utility piping

FAQ

Socket Weld Reducer Insert: common questions

Which MSS standard covers reducer inserts?

MSS SP-79, Socket Welding Reducer Inserts. The inserts fit into the sockets of standard ASME B16.11 socket weld fittings such as tees, elbows and couplings of the same class.

How is a reducer insert installed?

The spigot end is inserted into the socket of the fitting and fillet welded, then the smaller pipe is inserted into the insert's socket and fillet welded. Leave the usual expansion gap at each socket bottom.

Why use an insert instead of a reducing tee?

Inserts let you use standard equal tees and elbows with a smaller pipe, so you stock fewer special reducing fittings and can make up reductions on site.

Is the class of the insert tied to the fitting?

Yes. Use an insert of the same class as the fitting it goes into — Class 3000 with Class 3000 fittings, Class 6000 with Class 6000.

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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