GOST-17378-Concentric-Eccentric-Reducer

GOST 17378 Concentric Eccentric Reducer

GOST 17378 Reducer Manufacturer

GOST 17378 is a Russian standard that defines the specifications for concentric and eccentric reducers used in piping systems. These are typically butt-welded fittings used to connect pipes of different diameters, similar to reducers found in ASME/ANSI or DIN standards.

Reducer also called Transitions,A pipe reducer is a type of pipe fitting used in piping systems to connect two pipes of different diameters.

Product Types:

  • Concentric reducer: Centerline remains consistent
  • Eccentric reducer: One side is flat (used to maintain bottom/top alignment in horizontal piping)
GOST 17378 reducer Specifications:
ParameterDescription
StandardGOST 17378-2001 (latest revision)
TypeButt-welded reducer (eccentric or concentric)
MaterialsCarbon steel, alloy steel, stainless steel (based on GOST, TU, or customer spec)
CT20,09G2S 
 304, 304L, 316, 316L, 321, 347, 08Х18Н10, 10Х18Н10Т, 12Х18Н10Т, 20Х23Н13, 10Х17Н13М2Т, etc.
SizesDN 15 to DN 1000 (commonly)
GOST 17378-01

Dowload the gost 17378 standard pdf

This standard applies to seamless welded concentric and eccentric transitions from carbon and low – alloy steel.
The scope of application of the transitions is in accordance with Section 1 of GOST 17380.

GOST 17378 Dimension
GOST 17378 Reducer Dimension
GOST 17378 Reducer
GOST 17378 Reducer Dimensions

• Concentric transition of execution 1 D = 508 mm, T = 11 mm and D1 = 406.4 mm, T1 = 8.8 mm from steel grade 20:
Transition K 1-508×11-406.4×8.8 GOST 17378-01,

• the same, from steel 09G2S, for pipelines controlled by supervisory authorities:
Transition PC 1-508×11-406,4×8, 8-09G2S GOST 17378-01,

• eccentric transition of execution 2 D = 530 mm, T = 26 mm and D1 = 377 mm, T1 = 22 mm from steel grade 20:
Transition E 530×26-377×22 GOST 17378-01.

Related Standards:
  • GOST 17379 – Wall thicknesses for pipe fittings