MSS SP 97 Weldolet threadolet Sockolet

MSS SP 97 is a standard for Integrally Reinforced Forged Branch Outlet Fittings – Socket Welding, Threaded, and Butt welding Ends

Weldolet

Weldolet is the most common branch fititngs connections, it is with butt weld end to connect main run pipe (larger size) and  the branch pipe (smaller size)

The weldolet is ideal for replacing a tee on 90-degree branches with a reinforced connection that protects the branch pipe by reducing stress concentration due to its shape and size.
Its beveled ends allow an easy installation by BW welding on the previously cut main and on the branch pipe which will have an internal diameter or Schedule generally smaller or equal to the weldolet.

Weldolets are used to provide an outlet area from a larger to a smaller pipe connection point.

Threadolet dimensions are manufactured according to MSS SP 97

Sockolet

Sockolet is a branch outolet  pipe fittings with a  Socket Welding End for branch  pipe connection.The othe end welded on the run pipe or the header,

The sockolet has full size or reduced size. Full size means to take a branch of same size as the run pipe, for example, 2 inch to 2 inch. sockolet  Reducing size is when the branch size is smaller than the running pipe size, for example, 1 inche to 3 inch.

Sockolet is designed for specific conditions based on Process piping Code ASME B31.3;  MSS-SP-97 provides dimension requirements for standard 90° self-reinforced branch connection with butt, socket, and threaded end types.

Sockolet Dimemsions as below

Pressure Ratings: 3000#, 6000#

Material available:

Carbon steel: ASTM A105 Weldolet, A105N, A350LF2 weldolet,

Stainless steel:ASTM A182 F304, F304L,F316,F316L, F317L, F321, F321H, F347, F347H, F310, F44,F51,S31803, A182, F53,S32750

Line Pipe: ASTM A694 F42,F46,F52,F56,F60,F65,F70,

Alloy steel: A182 F12,F11 weldolet,F22,F5,F9,F91,ECT

Special Material: Monel, Duplex S.S, Alloy, Inconel, 904L etc

Threadolet

Threaded Outlet is a type of branch connection thread fittings used for connecting run pipes.

Threadolet dimensions are manufactured according to MSS SP 97

The thread type could be NPT,BSPT etc

MSS SP-97-2012 

Integrally Reinforced Forged Branch Outlet Fittings – Socket Welding, Threaded and Buttwelding Ends

MSS SP-97-2019 includes essential dimensions, finish, tolerances, testing, marking, material, and minimum strength requirements for 90° and 45° integrally reinforced forged branch outlet fittings of buttwelding, socket welding, and threaded types. 

Unless specified otherwise by the manufacturer, conventional integrally reinforced forged branch outlet fittings are intended for the following header by branch combinations: STD × STD, XS × XS, SCH. 160 × SCH 160, XXS × XXS, XS × 3000, SCH 160 × 6000, and XXS × 9000. When the run and branch pipes are of differing or mixed schedules, then the selection of the branch connection shall be determined by contacting the manufacturer. Such selections shall be agreed upon by purchaser and manufacturer at time of order and may involve supplemental marking requirements determined by other standards (e.g., material grade determination, other factors). See Section 1.3. Mixed schedule branch outlet fittings are unique to the design of each system, and thus outside the scope of this Standard Practice. The adequacy of the design for light, intermediate, and heavy wall branch outlet fittings may be established by mathematical analysis as contained in the applicable pressure vessel or piping codes, or by finite element analysis.