Pipe and piping fittings
Concentric reducer
Regulation of upstream or downstream pressure within a required range
Specialist selection guide
What should be reviewed before selecting this product?
A concentric reducer changes line size about a common centreline. Length, reduction ratio, end walls and orientation affect velocity, pressure loss, stress and the potential for gas or liquid pockets.
Technical selection path
- 1
Define large end, small end and both end schedules
- 2
Calculate downstream velocity and pressure loss
- 3
Match concentric or eccentric form to line arrangement
- 4
Check end bevels and wall against both pipes
- 5
Review flow direction and cavitation limits
Key strengths
- Symmetrical transition and simple installation
- Suitable for vertical and many horizontal lines
- Available in many size and schedule combinations
Selection limitations
- Can create a vapour pocket in horizontal pump suction
- A large reduction increases velocity and pressure loss
- The two ends may require different wall thicknesses
Typical applications
Where can this option be considered?
- Vertical line size changes
- Nozzle and equipment transitions
- Header and branch size transitions
Reference standards
A standard does not replace the project specification
Common technical questions
Concise answers before enquiry
Concentric or eccentric: which is appropriate?
Selection depends on line orientation, fluid phase, pump suction or discharge and the need to avoid vapour or liquid pockets.
Does reducer orientation matter?
Yes. Orientation directly affects phase trapping, venting, draining and pump performance.
Steam, gas, water and process networks with varying demand
Pressure ratio, cavitation, noise and minimum-to-maximum flow
Initial review sheet
Technical attributes to review
Final values must come from project specifications, calculations and manufacturer data. This table defines the information scope.
FamilyButt-weld fittings
Main groupPipe and piping fittings
Materials to evaluateCarbon steel, Stainless steel, Alloy steel, Nickel alloy
Connections to evaluateButt-weld
Typical mediaProcess, Steam, Gas, Liquid
Relevant industriesOil and gas, Refining, Petrochemical, Power generation, Water and utilities
Reference standardsASME B16.9 · ASME B16.28 · MSS SP-75
Enquiry checklist
Include this information with your request
Size and schedule
Radius and angle
Reduction type
Material grade
Dimensional tolerance
Testing and certification
Before substitution
A matching name does not guarantee interchangeability
Installation dimensions, pressure rating, wetted materials, sealing design, construction standard, testing and documentation must be checked independently.
Adjacent types
Other options in this family
Final technical approval is required
This page is educational and intended for initial screening. Final selection must be approved against project requirements, actual service conditions and manufacturer documentation.
Send request for review