Coliter ® Silent Check Valve – PN1.0~2.5, ≤80°C, Slow-Closing Design to Eliminate Water Hammer in Pump Systems
HC42X/DRVZ Silent Check Valve – Ductile Iron or Stainless Steel Check Valve with Spring-Assisted Slow Closure for Quiet, Water Hammer-Free Operation
The Coliter® HC42X/DRVZ Silent Check Valve is an advanced axial-flow check valve engineered to prevent backflow while eliminating water hammer and noise in pumping stations, HVAC systems, fire protection networks, and municipal water pipelines. Unlike conventional swing or lift check valves that slam shut during flow reversal, the HC42X/DRVZ features a patented slow-closing, spring-assisted mechanism that ensures smooth, controlled closure—dramatically reducing pressure surges and system stress. The internal flow passage is fully streamlined with a fluid guide structure, minimizing turbulence and pressure drop. A multi-element sealing system combines metal and elastomer (NBR or EPDM) components, enabling bubble-tight shut-off even at low pressures without leakage—overcoming the poor low-pressure sealing of traditional check valves. Constructed with a ductile iron, cast steel, or stainless steel body, a WCB or CF8 disc with rubber coating, and a corrosion-resistant 06Cr19Ni10 (304) spring, it ensures long-term durability. Rated for PN1.0, PN1.6, or PN2.5 (1.0–2.5 MPa), it operates reliably at temperatures up to 80°C and is suitable for water, oil, and similar media. Compliant with GB/T 21387 (design & face-to-face length) and GB/T 13927 (testing), available in sizes from DN50 to DN800 with flanged ends. Ideal for protecting pumps and pipelines, the HC42X/DRVZ delivers silent, maintenance-free, and impact-free reverse-flow protection.
Installation diagram
Product Description
| DN | 50 | 65 | 80 | 100 | 125 | 150 | 200 | 250 | 300 | 350 | 400 | 450 | 500 | 600 | 700 | 800 | 900 |
| L | 120 | 150 | 180 | 240 | 300 | 350 | 450 | 500 | 550 | 575 | 600 | 650 | 700 | 800 | 980 | 1120 | 1300 |
This product is designed by our engineers and technicians with reference to advanced products of the same type at home and abroad. The internal flow passage is streamlined and equipped with fluid guide, which greatly reduces the fluid resistance. The valve is mainly used at the outlet of the water pump or other places to prevent the backflow of the medium, which can effectively prevent the water hammer impact and noise generated when the medium of the ordinary check valve backflows, thus extending the service life. Multi-element sealing structure is adopted, metal and rubber are combined, and the seating surface of the valve seat is sealed with a core, which can be closed tightly under medium and low pressure conditions without leakage, overcoming the shortcomings of poor sealing performance of general check valves. Welcome to purchase!
Performance Standard
- Design Standards: GB/T21387
- Structure Length Standard: GB/T21387
- Flange Standard: GB/T9124.1, GB/T1241.6
- Test Standard: GB/T13927
Main Performance Specification
| Nominal Pressure PN | 1.0MPa | 1.6MPa | 2.5MPa |
| Shell Test Pressure | 1.5MPa | 2.4MPa | 3.75MPa |
| Seal Test Pressure | 1.1MPa | 1.76MPa | 2.75MPa |
| Operating Temperature | <80°C | ||
| Applicable Media | Water, oil, etc. | ||
Material of Main Parts
| Part | Material |
|---|---|
| Valve Body | Ductile iron, cast steel, stainless steel |
| Disc | WCB, CF8+NBR, EPDM |
| Stem | 2Cr13, F304 |
| Spring | 06Cr19Ni10 |
| Conductor | Ductile iron, cast steel, stainless steel |
Product Inquiry
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Faq - Frequent questions
Introduction to Check valve
Coliter®’s check valves prevent backflow and water hammer in pumping stations, HVAC systems, fire protection, and municipal water networks. The series includes the H44H cast steel swing check valve for high-pressure service, H41H cast steel lift check valve for vertical flow, H44W stainless steel swing type (304/316) for corrosive media, H44X (SFCV) rubber disc silent check valve for quiet operation, HC41X energy-saving silent check valve with spring-assisted closure, and HC42X/DRVZ slow-closing silent check valve to eliminate water hammer. Available in flanged or threaded connections (DN15–DN600), rated at PN10–PN40, and compliant with GB/T 12235 and API 598 standards—ensuring reliable, maintenance-free reverse-flow protection across diverse applications.
