H 74W/H Factory Direct Sale SS304 SS316 Pn16/Pn25 Valve Thin Check Valve for Oil/Water/Gas System

Product Description

Product Description

Our industrial check valve is a critical flow control component designed to prevent reverse flow in pipelines, ensuring the safe and efficient operation of fluid systems across diverse industries.

Featuring a robust design, it operates automatically—opening to allow media flow in one direction and closing tightly to block reverse flow, eliminating the risk of equipment damage, backflow contamination, or operational inefficiencies. 

Available in multiple types, including swing check valves (with a pivoting disc for low-pressure drop and high flow capacity), lift check valves (with a vertical-moving disc for superior sealing in moderate pressure systems), and dual plate check valves (for rapid closing in high-flow applications), our product caters to varied operational needs.

Constructed from premium materials such as stainless steel (SS304/SS316), carbon steel (WCB), ductile iron, or PTFE-lined plastic, it withstands corrosive, high-temperature, or abrasive media (including water, oil, gas, chemicals, and steam). Sealing options range from metal-to-metal hard seals (for extreme temperatures up to 1200℃ and pressures up to PN100) to elastomeric soft seals (for low-pressure, moderate-temperature applications), ensuring leak-tight performance in any scenario.

Available in sizes from DN15 to DN600 (or 1/2" to 24") and pressure ratings from PN10 to PN100 (or ANSI Class 150 to 600), our check valves comply with international standards like  ASME B16.34, and ISO 5208. Connection types include flanged, wafer, threaded, and welded, enabling seamless integration into existing pipelines.

Ideal for applications in oil & gas, chemical processing, power generation, water treatment, and HVAC systems, our check valve delivers reliable performance, minimal maintenance, and extended service life—making it the trusted choice for preventing backflow in critical infrastructure.

Product Advantages

1. Automatic Operation:It operates without external power, opening and closing automatically based on the direction of media flow, reducing the need for manual intervention and control systems.

2. Backflow Prevention:Effectively prevents the reverse flow of media, protecting downstream equipment (such as pumps, compressors, and pipelines) from damage caused by backflow and avoiding operational disruptions.

3. Diverse Types & Wide Adaptability:Available in various types like swing check valves, lift check valves, dual plate check valves, etc., suitable for different media (water, oil, gas, chemicals, steam) and working conditions (high pressure, high temperature, corrosive environments).

4. Simple Structure & Easy Maintenance:With a relatively simple internal structure, it has fewer components, making installation, inspection, and maintenance convenient. Routine maintenance mainly involves checking the sealing performance and cleaning.

5. Energy Saving:By preventing backflow, it reduces energy waste caused by the reverse operation of equipment, improving the overall energy efficiency of the system.

6. Long Service Life:Made of high-quality materials (such as stainless steel, carbon steel, ductile iron) and advanced sealing technologies (metal hard seals, elastomeric soft seals), it can withstand harsh working conditions and has a long service life.

 7. Wide Sizing & Pressure Range:Available in a wide range of sizes (from DN15 to DN600+) and pressure ratings (from PN10 to PN100+ or ANSI Class 150 to 600+), meeting the needs of different pipeline systems.

8. Compliance with International Standards:Manufactured in compliance with international standards (such as ASME B16.34 ISO 5208), ensuring product quality and interchangeability.

How does valve work?

Check valves (also called non-return valves) are automatic flow control components that only allow media to flow in one direction and block reverse flow—no external power is required. Their operation relies on the pressure difference between the valve's inlet (upstream) and outlet (downstream).
When media flows forward, upstream pressure pushes the valve's closing element (e.g., disc, flap, piston) away from the seat, overcoming resistance from weight, spring force (if equipped) or backpressure. This opens the valve for smooth media passage. When upstream pressure drops or downstream pressure exceeds it (causing backflow), backpressure pushes the closing element tightly against the seat, forming a tight seal to stop reverse flow and protect equipment.

Common types have slight structural differences:
* Swing check valve: A hinged flap swings open with forward flow (low resistance, ideal for large diameters) and closes via backpressure/weight.

* Lift check valve: A piston/disc moves vertically—forward pressure lifts it open, reverse pressure pushes it closed (precise sealing for medium pressure).

* Spring-loaded check valve: A spring preloads the closing element, ensuring fast closing even in vertical installations or high-pressure systems.

Widely used in water treatment, oil & gas, and power generation, they offer reliable backflow protection with minimal maintenance.

Product Parameters

 1.Size & Connection:

* Nominal Diameter (DN): Standard size representing the valve's passage diameter (e.g., DN15, DN50, DN200), matching pipeline dimensions for seamless installation.

* Nominal Pipe Size (NPS): Imperial size equivalent to DN (e.g., 1/2", 2", 8"), commonly used in North American markets.

* Connection Type: The way the valve attaches to pipelines, including flanged (ASME B16.5), threaded (NPT/BSP), wafer (for compact spaces), and welded (socket weld/butt weld).

2. Pressure Rating:
* Nominal Pressure (PN): Maximum pressure the valve can withstand at rated temperature (e.g., PN10, PN16, PN40), in bar or MPa.

* Class Rating: Imperial pressure standard (e.g., ANSI Class 150, Class 300, Class 600), corresponding to specific pressure values at different temperatures (e.g., Class 150 ≈ PN20 at 100℃).

* Maximum Working Pressure (MWP): Actual safe pressure limit under the valve's intended operating temperature, not exceeding PN/Class rating.

3. Temperature Range:
* Operating Temperature Range: The minimum and maximum temperature the valve can tolerate (e.g., -40℃~120℃ for EPDM seals, -20℃~538℃ for metal hard seals), determined by material (body, seals) and application media (steam, cryogenic fluids).

4. Material:
* Body Material: Determines corrosion resistance and strength, such as stainless steel (SS304/SS316 for corrosive media), carbon steel (WCB for high pressure), ductile iron (for low-cost industrial use), and PTFE-lined plastic (for acid/alkali fluids).

* Seal Material: Affects sealing performance and temperature resistance, including EPDM (low-temperature water/gas), PTFE (corrosive chemicals), and metal (stainless steel, Stellite alloy for high temperature/pressure).

* Trim Material: Components like valve disc, seat, and spindle, often using stainless steel or hardened alloys to resist wear.

5. Flow & Performance:
* Flow Coefficient (Cv/Kv): Measures the valve's ability to pass media—higher Cv/Kv means lower flow resistance (critical for large-flow pipelines like water supply systems).

* Closing Speed: Time taken to seal against reverse flow, with fast-closing types (e.g., dual-plate, spring-loaded) reducing water hammer (pressure surges) in pipelines.

1. Material	A351 CF8M/CF8/CF3/CF3m, A216 WCB,A352 LCB,A217 WC6/WC9
2. Size	DN15~DN300
3. Working Pressure	150lb~1500lb
4. Connection Ends	Flange
5. Working Temp.	-196~540ºC
6.Delivery Time	10~25 Days
7.Package	Wooden Box
8.Shipping Port	Ningbo/Shanghai, China
9.Shipping Terms	Exw, FOB, CFR, CIF, etc.
10.Payment Terms	T/T, Western Union, PayPal, etc.
	30% prepayment, 70% balance paid before shipping or against copy of BL