ASME B16.11 Socket Weld Pipe Fittings

ASME B16.11 socket weld pipe fittings are pipe fittings with a socket and a spigot structure, used to connect two pipes. The socket is one end of the pipe fitting, whose inner diameter is slightly larger than the outer diameter of the pipe, and is used to accommodate the inserted pipe; the spigot is the other end of the pipe fitting, whose outer diameter matches the inner diameter of the pipe, and can be inserted into the socket of another pipe or pipe fitting.

Socket weld pipe fittings are widely used in various industries, such as petroleum, chemical, pharmaceutical, water treatment and other industrial fields, as well as pipe connections in buildings and other structures.

ASME B16.11 Socket Weld Pipe Fittings Specification

Type	Elbow, Tee, Cross, Coupling, Cap, Lateral
Size Range	1/8"- 4" / DN6 - DN100
Pressure Rating	Class 3000LBS, 6000Lbs, 9000lbs.
Carbon Steel	ASTM A105 / A105N, ASTM A350 LF2, A694 F42 / 46 / 56 / 60 / 65
Alloy Steel	ASTM A182 F11 / 12 / 22 / 5 / 9 / 91 / 92 / 22
Stainless Steel	ASTM A182 F304 / 304L / 304H, 316 / 316L, 321, 310S, 317, 347, 904L
Duplex Stainless Steel	ASTM A182 F51, F53, F44

Standard Scope

ASME B16.11 socket weld pipe fittings covers ratings, dimensions, tolerances marking, and material requirements for forged fittings,both socket-welding and threaded, as illustrated in Tables 1 through 5 and Tables I-1 through I-5, inclusive.

Fitting Types/Configuration.

Types of fittings covered by this Standard are shown in Table 6, by class and size range. Fittings shown in Tables 1 through 5 and Tables I-1 through I-5 may also be made with combi-nations of socket-welding and threaded ends.

Special Fittings.

Fittings with special dimensions,threads,or counter bores may be made by agreement between the manufacturer and purchaser.When such fittings meet all other stipulations of this Standard, they shall be considered in compliance therewith, provided they are appropriately marked (see section 4).

Pressure Rating for ASME B16.11 Forged Pipe Fittings

These fittings are designated as Class 2000, 3000, and 6000 for threaded end fittings and Class 3000, 6000, and 9000 for socket-weld end fittings.

Basis of Rating

The schedule of pipe corresponding to each Class designation of fittings for rating purposes is shown in below table. Design temperature and other service condition shall be limited as provided by the applicable piping code or regulation for the material of construction of the fitting. With these limits, it defines the minimum pipe wall thickness.

Correlation of Fittings Class with Schedule Number or Wall Designation of Pipe for Calculationof Rating

Table 1

Class Designation of Fitting	Type of Fitting	Pipe Used for Rating Basis [Note(1)]
		Schedule No.	Wall Designation
2000	Threaded	80	XS
3000	Threaded	160
6000	Threaded	…	XXS
3000	Socket-welding	80	XS
6000	Socket-welding	160
9000	Socket-welding	…	XXS

Note: (1) This Table is not intended to restruct the use of pipe of thinner or thicker wall with fittings.Pipeactually used may be thinner or thicker in nominal wall than that shown in this Table. When thinner pipe isused,its strength may govern the rating. When thicker pipe isused(e.g.formechanical strength), the strengthof the the fitting governs the rating.

Pressure Test Capability

This standard does not require a pressure test, but the fittings shall be able to withstand the hydrostatic test pressure required by the applicable pipe code to accommodate seamless pipe of material equivalent to the fittings forging and of the schedule or wall thickness associated with the fittings grade and end connection of table 1.

Nominal  Pipe  Size	Socket Weld Fittings Weight in KG
	45-Deg Elbow			90-Deg Elbow			Tee			Cross			Coupling			Half Coupling			Cap
	3000	6000	9000	3000	6000	9000	3000	6000	9000	3000	6000	9000	3000	6000	9000	3000	6000	9000	3000	6000	9000
3/8	0.08	0.12	0.19	0.09	0.14		0.12	0.20		0.16	0.24		0.05	0.08		0.05	0.08		0.05	0.08
1/2	0.13	0.20	0.29	0.15	0.22	0.33	0.20	0.31	0.46	0.26	0.39	0.58	0.09	0.13	0.19	0.09	0.13	0.19	0.09	0.13	0.19
3/4	0.21	0.32	0.48	0.24	0.36	0.53	0.33	0.50	0.75	0.41	0.63	0.94	0.14	0.21	0.31	0.14	0.21	0.31	0.14	0.21	0.31
1	0.34	0.51	0.76	0.38	0.57	0.86	0.53	0.80	1.20	0.67	1.00	1.51	0.22	0.34	0.51	0.22	0.34	0.51	0.22	0.34	0.51
11/4	0.54	0.81	1.22	0.60	0.91	1.36	0.84	1.27	1.90	1.06	1.60	2.40	0.36	0.54	0.81	0.36	0.54	0.81	0.36	0.54	0.81
11/2	0.86	1.29	1.94	0.96	1.44	2.16	1.35	2.02	3.03	1.69	2.54	3.81	0.57	0.86	1.29	0.57	0.86	1.29	0.57	0.86	1.29
2	1.38	2.08	3.12	1.54	2.31	3.46	2.16	3.23	4.84	2.71	4.06	6.09	0.92	1.38	2.07	0.92	1.38	2.07	0.92	1.38	2.07
21/2	2.21			2.46			3.44			4.33
3	3.53			3.93			5.50			6.92
4	5.66			6.29			8.80			11.08

Tolerance for Socket Weld Pipe Fittings

TOLERANCES FOR SW FITTINGS
Nominal Size		All Fittings		Elbows, Tees & Crosses	Couplings	Half- Couplings	Reducer Inserts			Unions
		Socket Bore Dia.	Bore Dia. of Fittings	Center to Bottom of Socket	Laying Lengths	Laying Lengths	Laying Length	Shank Dia.	Length	Laying Length
DN	NPS	B	D	A H	E	F	A	SD	SL	E
6~8	1/8~1/4	+0.4 0	+1.5 0	± 1.0	± 1.5	± 1.0	+1.5 0	± 0.25	0 -1.5	± 1.5
10~20	3/8~3/4	+0.4 0	+1.5 0	± 1.5	± 3.0	± 1.5	+1.5 0	± 0.25	0 -1.5	± 3.0
25~40	1~11/2	+0.4 0	+1.5 0	± 2.0	± 4.0	± 2.0	+2.0 0	± 0.25	0 -2.0	± 4.0
50	2	+0.5 0	+1.5 0	± 2.0	± 4.0	± 2.0	+2.0 0	± 0.5	0 -2.0	± 4.0
65~80	21/2~3	+0.5 0	+3.0 0	± 2.5	± 5.0	± 2.5	+2.5 0	± 0.5	0 -2.5	± 5.0
100	4	+0.5 0	+3.0 0	± 2.5	± 5.0	± 2.5	+2.5 0	± 0.7	0 -2.5	-

Types of Socket Weld Pipe Fittings

Socket Weld Fittings types include Elbow , Tee, Cross, Coupling, Union, Cap .

●90 Degree Socket Weld Elbow: It is the most common type of socket elbow in ASME B16.11 socket weld pipe fittings, used to achieve right-angle turns in pipes.

●45 Degree Socket Weld Elbow: The bending angle is 45 degrees, and it is often used in places where a smaller angle turn is required in the pipe system. It can make the direction of the pipe smoother and reduce the resistance of the fluid in the pipe.

●Socket Weld Tee: There are straight tees and reducing tees. The three interfaces of the straight tee are perpendicular to each other, and are used to divide a main pipe into two branches or merge two branches into one main pipe; the interface of the reducing tee has a certain angle, which is suitable for branch connections at some special angles.

●Socket Weld Cross : Used to connect four pipes to realize multi-directional branching or confluence of pipes. In some complex industrial pipe networks, cross fittings can be used to connect pipes in different directions so that the fluid can flow along a predetermined path.

●Socket Weld Coupling : The coupling is a pipe fitting used to connect two pipes, usually made of metal or plastic. Its structural characteristics are that one end is a socket and the other end is a spigot.

●Socket Weld Cap : A pipe cap is a ASME B16.11 socket weld pipe fitting used to close the end of a pipe. It has a simple structure, one end is open and is used to be put on the end of the pipe, and the other end is a closed end.

●Socket Weld Union : A union is a pipe connector that can be easily disassembled and assembled, consisting of a male connector, a female connector and a sealing gasket.

ASME B16.11 SW Pipe Fittings Structural Features

Good sealing performance: Sealing materials such as rubber sealing rings, sealants, etc. are usually used to seal the socket weld pipe fittings. This sealing structure can effectively prevent the leakage of the medium in the pipeline and ensure the sealing of the pipeline system.

Easy installation: The connection method of the socket weld pipe fittings is relatively simple and does not require complex welding or thread processing equipment. During the installation process, you only need to insert the pipe into the socket and then fix it in a certain way, which greatly saves installation time and cost.

Strong removability: Compared with welded pipe fittings, ASME B16.11 socket weld pipe fittings have better removability. When the pipeline system needs to be repaired, replaced or modified, the spigot fittings can be easily disassembled without causing significant damage to the pipeline.

Specific Marking

Specific Marking. The marking shall include (but is not limited to) the following:

a. Manufacturer’s Name or Trademark

b. Material Identification. 

Material shall be identified in accordance with the marking requirements of either the appropriate ASTM Fitting or ASTM Forging Specifications (see para. 5.1).

c. Product Conformance. 

Fittings covered under para.

1.1.1 shall be marked with either the ASTM Fittings Specification material identification (e.g., “WP______”) or the symbol “B16” to denote conformance to this

Standard. Fittings covered under para. 1.1.2 shall be marked with a supplementary suffix as follows:

(1) For ASTM A234, A403, A420, and A815, suffix the material grade with “S58” (see ASTM A960 Supplementary Requirement S58).

(2) For ASTM Fitting Specifications B366, suffix the material grade with “SPLD.”

(3) For all ASTM Forging Specifications, suffix “B16” with “SPLD.”

d. Class Designation.

2000, 3000, 6000, or 9000, as applicable. Alternatively, the designation 2M, 3M, 6M, or 9M, as applicable, may be used where M stands

for 1000.

e. Size. 

The nominal pipe size related to the end connections.