H7B41X hydraulic control check valve

H7B41X hydraulic control check valve

  • Product Model: H7B41X Series Hydraulic Control Check Valve (H7B41X-16 / H7B41X-16C)
  • Pressure Rating: PN16 (1.6MPa)
  • Connection Type: Flanged connection
  • Structure: Normally closed pressure-controlled lift check valve
  • Body Material: Gray cast iron (H7B41X-16) / WCB cast steel (H7B41X-16C)
  • Sealing Material: 2Cr13 stainless steel valve disc and seat
  • Spring Material: 50CrVA alloy steel
  • Applicable Media: Water, oil products
  • Working Temperature: ≤70℃
  • Core Function: Automatically opens/closes with pipeline pressure changes to prevent boiler overflow and pump backflow
  • Application Scenarios: Normal pressure boiler return water pipelines, water and oil pipeline systems

Gaoshan Valve — H7B41X Liquid Control Check Valve

Model: H7B41X-16Q / H7B41X-16C  |  Pressure: PN16  |  Connection: Flanged  |  Operation: Self-Acting Hydraulic Control  |  Medium: Water, Petroleum

Pressure Class
PN16
DN Range
DN40–DN200
Body Material
Gray Cast Iron / WCB
Max. Temperature
≤70°C
Connection
Flanged
Operation Type
Self-Acting Hydraulic

Water
Petroleum Products
Non-Corrosive Media

Core Strengths

Self-Acting Hydraulic Control
Utilizes changes in pipeline pressure to automatically open and close the valve. No external power source, solenoid coils, or control wiring required—eliminates electrical failure risks in critical boiler return circuits.
Normally-Closed Safety Design
The valve remains closed under static conditions and opens only when pipeline pressure exceeds the spring preload. This fail-safe behavior prevents boiler overflow caused by sudden power loss or pump shutdown.
Cost-Effective Solenoid Alternative
Fully replaces expensive electromagnetic control systems in natural-pressure boiler return lines. Delivers equivalent automatic shutoff functionality with simpler maintenance, lower energy use, and no electrical infrastructure.
Dual Material Configuration
H7B41X-16Q features a gray cast iron body for standard water services, while H7B41X-16C uses WCB cast steel for higher mechanical strength and broader application flexibility.
2Cr13 Stainless Steel Trim
Stem, disc, and seat ring are precision-machined from 2Cr13 stainless steel for excellent corrosion resistance, wear durability, and consistent sealing performance over long service life.
High-Strength Spring Element
Equipped with 50CrVA spring steel (H7B41X-16Q) or alloy spring steel (H7B41X-16C), delivering stable preload force and reliable valve closure even after millions of operating cycles.

Product Overview

The H7B41X liquid control check valve is a self-acting hydraulic valve specifically designed for boiler return-water pipelines in natural-pressure heating systems. It opens automatically when forward pipeline pressure exceeds the spring preload, allowing return water to flow back to the boiler. When pump shutdown or power failure causes flow to stop, the spring-assisted disc closes immediately, preventing boiler overflow and water hammer. This intelligent pressure-responsive design eliminates the need for costly electromagnetic control systems while delivering equivalent automatic shutoff protection. The H7B41X-16Q model uses gray cast iron body construction for general water services, while the H7B41X-16C model features WCB cast steel body for enhanced mechanical properties. Both models incorporate 2Cr13 stainless steel internal trim and high-strength alloy springs to ensure reliable, long-term operation at temperatures up to 70°C.

Performance Specifications

ParameterH7B41X-16QH7B41X-16C
Nominal Pressure PN (MPa)1.6
Shell Test Pressure (MPa)2.4
Seal Test Pressure (MPa)1.8
Max. Working Temperature≤70°C
Applicable MediumWater, Petroleum, etc.
Operation PrincipleSelf-acting hydraulic pressure control
Valve Status at RestNormally closed

Main Component Materials

ModelValve Body / BonnetStem / Disc / Seat RingSpring
H7B41X-16QGray Cast Iron2Cr13 Stainless Steel50CrVA Spring Steel
H7B41X-16CWCB Cast Steel2Cr13 Stainless SteelSpring Steel

Main Dimensions & Weights

DN (mm)40506580100125150200
L (mm)220250280310350400450500
H (mm)175175195215215240240280
H1 (mm)115115135155155170170190
Weight (kg)282834404978111155

* Dimensions apply to PN16 pressure class. All values are for reference only. Contact us for detailed engineering drawings for your specific model.

Structure Drawing

H7B41X-16Q H7B41X-16C liquid control check valve structure drawing showing flanged body, spring-loaded disc assembly, bonnet, and hydraulic control chamber with flow direction

Design & Manufacturing Standards

  • Design Standard: GB/T 12236
  • Face-to-Face Dimensions: GB/T 12221
  • Flange Standards: GB/T 9113, JB/T 79, HG/T 20596
  • Testing & Inspection: GB/T 13927, JB/T 9092
  • Applicable International Standards: EN 13709, EN 558 (optional)

Installation & Maintenance Guidelines

  • Boiler Return Line Position: Install the valve on the return-water pipeline of natural-pressure boilers. The valve must be positioned where pipeline pressure fluctuations during normal pump operation and shutdown are clearly transmitted to the valve chamber.
  • Flow Direction: Ensure medium flows in the direction indicated by the arrow cast on the valve body. Reverse installation will cause the valve to fail to open or close correctly.
  • Horizontal Installation Preferred: Install the valve horizontally with the bonnet facing upward for optimal spring performance and disc movement. Avoid inverted or vertical orientations unless specifically approved.
  • Pipeline Support: The valve body should not bear pipeline weight. Install independent support brackets, especially for DN125 and larger sizes, to prevent flange stress and distortion.
  • Maintenance: Periodically inspect the disc, seat ring, and spring for wear, corrosion, or sediment buildup. Clean the control chamber passages to ensure sensitive pressure response. Replace the spring if preload force decreases.

Application Fields

Boiler Return Water Systems
Natural-Pressure Heating Circuits
Hot Water Distribution Networks
Petroleum Pipeline Protection
Industrial Circulating Water
HVAC & Building Heating

Get a Quote & Technical Support

Contact Gaoshan Valve today for detailed dimension sheets, CAD drawings, and customized liquid control check valve solutions for your boiler return system.

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