Pressure reducing valve - Direct Acting for liquids & gases - REAH20 | Miyawaki

Miyawaki REAH20 Direct-Acting Pressure Reducer for Liquids and Gases

The Miyawaki REAH20 is a self-acting pressure reducer designed for both compressible and incompressible media, including air, technical gases, water, oil, and neutral process fluids. The downstream pressure is internally sensed within the control chamber, directly adjusting the valve opening without external energy or impulse lines.

Technical Specifications

• DN15–DN200.
• Flanged connection DIN standard.
• Body: cast steel GP240GH / GS-C25 / 1.0619.
• Body class: PN40 as per Miyawaki official page; distributor page also lists PN63 / PN100 options.
• PMO up to 4.0 MPa and TMO up to 400°C for PN40.
• Downstream pressure setting ranges: 0.05–1.6 MPa.
• Settings below 0.05 MPa or above 1.6 MPa require technical evaluation.
• Maximum pressure reduction ratio: 25:1.

Construction and Operation

The valve operates with a piston-driven mechanism and O-ring, without a diaphragm. The conical disc rotates freely 360° to distribute seat wear more evenly. Additional gauges, special connections, and soft sealing for leakage class VI are available.

Applications

Used in compressed air lines, natural gas, LNG, fuel tanks, lube-oil lines, pre-heater units, process water, and technical gases like acetylene, ammonia, and CO₂, with material and sealing compatibility confirmation.

Selection Criteria

For sizing, p1, p2, flow rate, medium, temperature, DN, Kvs, required leakage class, and reduction ratio are needed. For ratios above 25:1, consider two-stage pressure reduction.