Eccentric Reducer Carbon Steel — Factory Direct Supplier | Huaxia-Steel

The eccentric reducer is a butt-weld pipe fitting that connects two pipes of different diameters while keeping one side flat. Unlike a concentric reducer, which is symmetrical, the eccentric reducer maintains a flat side (either top or bottom) so that the pipe run can drain completely or be aligned flat against a support rack. This is essential in pump suction lines, process piping and drainage systems where air pockets or liquid pooling must be avoided. Huaxia-Steel manufactures eccentric reducers in carbon steel to ASME B16.9, MSS SP-75 and DIN 2616 standards.

Product Specifications

Parameter	Specification
Standard	ASME B16.9, MSS SP-75, DIN 2616
Material	ASTM A234 WPB (carbon steel)
Size range	1/2″ to 48″ (DN15 to DN1200)
Wall thickness schedule	SCH 10, SCH 20, SCH 40, SCH 80, SCH 160, XXS
End type	Butt-weld (bevelled ends)
Reducer type	Eccentric (flat on one side)
Orientation	Flat on top (FOC) or flat on bottom (FBC)
Surface finish	Painted, black, galvanised or pickled
Manufacturing method	Hydraulic pressing or forging

Available Grades

Grade	Standard	Typical Application
ASTM A234 WPB	ASME	General-purpose carbon steel piping
ASTM A234 WPB (LTCS)	ASME	Low-temperature service to -46°C
ASTM A420 WPL6	ASME	Cryogenic service to -101°C
Q235 / Q345	GB	Chinese standard piping systems
ST37 / ST52	DIN	European standard piping

Dimensional Tolerances (ASME B16.9)

Dimension	Tolerance
Outside diameter (large end)	+/- 1.5 mm (up to 10″) / +/- 2.4 mm (over 10″)
Outside diameter (small end)	+/- 1.5 mm (up to 10″) / +/- 2.4 mm (over 10″)
Overall length (L)	+/- 3 mm (up to 10″) / +/- 5 mm (over 10″)
Wall thickness	Not less than 87.5% of nominal
Bevel angle	30° +/- 2.5°
Flat side deviation	≤ 1.5 mm per metre of length

Manufacturing Standards

• ASME B16.9 — Factory-made wrought butt-welding fittings; covers dimensions, tolerances and ratings.
• MSS SP-75 — Specification for high-test wrought butt-welding fittings; includes higher-strength grades.
• DIN 2616 — German standard for butt-welding reducers (eccentric and concentric).
• ASTM A234 — Standard specification for butt-welding fittings of carbon and alloy steel.

Applications

• Pump suction lines — eccentric reducers with flat side up prevent air pockets that can cause cavitation.
• Drainage and blow-down lines — eccentric reducers with flat side down ensure complete drainage.
• Process piping — transitions between pipe sizes in chemical, petrochemical and refinery systems.
• Compressor and turbine piping — size transitions with flat alignment for support rack mounting.
• Water treatment plants — flow transitions in piping manifolds.

Quality Assurance

• 100% visual inspection of bevel, surface and dimensions before shipment.
• Hardness test (HBW) on every batch; results recorded on the MTC.
• Dimensional verification with calibrated callipers and bevel protractors.
• Material grade confirmed by PMI (Positive Material Identification) on request.
• EN 10204 3.1 / 3.2 mill test certificates provided with every delivery.

Packaging and Shipping

• Reducers packed in wooden crates or steel pallets with rust-preventive oil.
• Each reducer marked with: size, schedule, material grade, heat number and standard.
• Fumigated wooden packaging for export (ISPM-15 compliant).
• Container loading: 15 – 25 MT per 20′ container depending on size mix.

Get a Quote on Eccentric Reducers

Huaxia-Steel manufactures eccentric reducers in carbon steel (A234 WPB), low-temperature carbon steel (A420 WPL6) and alloy steel grades. We supply sizes from 1/2″ to 48″ in all schedules with full EN 10204 3.1 / 3.2 MTC. Custom dimensions, non-standard schedules and special bevel preparations are available on request. Contact us for a competitive factory-direct quote.

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