Reducing Flange | ASME B16.5 Reducing Pipe Flanges
What Is a Reducing Flange?
A Reducing Flange is a special type of pipe flange used to connect pipes with different diameters in a piping system. It combines the function of a standard flange and a reducer, allowing the transition between a larger pipe and a smaller pipe.
Reducing flanges are commonly manufactured according to ASME B16.5 standards and are widely used in oil and gas pipelines, petrochemical plants, power generation systems, and industrial piping networks.
Because of their integrated design, reducing flanges help reduce the number of fittings and welding joints, improving pipeline efficiency and reducing installation costs.
Our Reducing flange are designed in compliance with international quality standards. Available in all types and pressure, these flanges are widely used for pipe-to-pipe connections. The reducing flange includes a flange with one specified diameter having a bore of a different and smaller diameter. Except for the bore and hub dimensions the reducing flange will have dimensions of the larger pipe size. To increase the size of the flange, these are used at the outlet side of the expansion joint. Also provides steel reducing flanges and stainless steel reducing flanges. It is the most economical method to make a transition in size.
ASME B16.5 Reducing Flange Standard
Reducing flanges are typically manufactured according to:
-
ASME B16.5 – Pipe Flanges and Flanged Fittings
-
ASME B16.47 – Large Diameter Flanges
-
ANSI B16.5 – Flange dimensional standards
These standards define the dimensions, pressure ratings, bolt patterns, and tolerances for reducing pipe flanges.
Reducing Flange Specifications
| Item | Specification |
|---|---|
| Standard | ASME B16.5 |
| Product Type | Reducing Flange |
| Size Range | 1/2″ – 24″ |
| Large Diameter | Up to 60″ (ASME B16.47) |
| Pressure Class | Class 150 – Class 2500 |
| Facing Type | RF / RTJ / FF |
Uses of reducing flanges:
- Reducing flanges are a little easier to bolt up than non-reducing flanges.
- They provide the most perfect solution when you need to connect different size flanges.
- These flanges are available in all types and pressures.
- Reducing flanges are fixed by welding, gluing or clamping flanges of equal dimensions, provided with different connecting pieces.
- They offer the simplest and least expensive method of mating two different sized flanges.
Type of reducing flanges: welding neck, slip-on, threaded.
Weld neck reducing flange
slip on reducing flange
Reducing flanges are designed for when there is a change in the pipe size. The predominate flange (dimensions) matching the larger pipe size (NPT) but having a smaller bore matching the smaller pipe size (NPT). These flanges normally come in blind, slip-on, threaded and weld neck flanges.
Materials of Reducing Flanges
Reducing flanges can be manufactured from various materials depending on the service conditions.
Carbon Steel
-
ASTM A105
-
ASTM A350 LF2
Stainless Steel
-
ASTM A182 F304 / F304L
-
ASTM A182 F316 / F316L
Alloy Steel
-
ASTM A182 F11
-
ASTM A182 F22
-
ASTM A182 F91
Advantages of Reducing Flanges
Reducing flanges provide several advantages in piping systems:
-
Allow connection between different pipe sizes
-
Reduce the need for additional pipe reducers
-
Simplify pipeline design
-
Reduce welding and installation work
-
Improve flow transition in piping systems
Applications of ASME Reducing Flanges
ASME reducing flanges are widely used in industrial piping systems where pipelines change diameter.
Typical applications include:
Oil and Gas Industry
-
Pipeline transportation systems
-
Offshore platforms
Petrochemical Plants
-
Process piping systems
-
Chemical transport pipelines
Power Generation
-
Boiler piping
-
Heat exchanger systems
Water Treatment Systems
-
Industrial water pipelines
-
Pump connection systems
Reducing Flange vs Standard Flange
| Feature | Reducing Flange | Standard Flange |
|---|---|---|
| Pipe Size | Different sizes | Same size |
| Function | Flange + reducer | Flange only |
| Installation | Fewer fittings required | Requires reducer fitting |
Reducing flanges provide a compact solution for connecting pipes of different diameters.
We supply high-quality ASME B16.5 reducing flanges manufactured according to international standards.
Our products provide:
-
Wide size range
-
Multiple material options
-
Strict quality inspection
-
Competitive factory pricing
All products can be supplied with EN 10204 3.1 Mill Test Certificates.
Related Products：
-
Lap Joint Flange
