Gate valves and blind valves are both used for pipeline isolation, but they operate on fundamentally different principles.In industrial piping systems, if the objective is true physical isolation (positive isolation), then a blind valve (Blind Valve / Line Blind Valve) is generally more reliable than conventional valves. Instead of relying on seat sealing, it isolates the medium through a solid blind plate, which defines both its application scope and engineering value. The key features of a blind valve can be understood from an engineering perspective as follows: 1. Absolute Physical Isolation If zero leakage is required, then conventional valves (such as gate valves or ball valves) introduce risk, as their performance depends on sealing integrity. Blind valves follow a different logic: ▶ If a solid plate is inserted, then the flow is completely blocked▶ If the blind plate is correctly positioned, then sealing failure is no longer a concern This makes blind valves more suitable for: ● Oil & gas pipeline isolation ● Flammable media (petroleum, LNG, chemicals) ● High temperature steam systems Engineering conclusion:If the project requires verifiable isolation, then a blind valve should be prioritized over sealing-dependent industrial valves. 2. Inline Operation Capability Traditional spade and spacer blinds typically require flange disassembly, which increases operational complexity and introduces safety risks. Blind valves (such as sliding blind valves and swing blind valves) are designed with a different approach: ▶ If frequent switching between operation and maintenance is required, then manual intervention must be minimized▶ If shutdown is not permitted, then switching must be performed under pressurized pipeline conditions (subject to specific design) Therefore: ● Sliding Blind Valve: suitable for limited space and higher automation requirements ● Swing Blind Valve: simple structure, suitable for medium to low switching frequency ● Spectacle Blind Valve: suitable for low-frequency operation and cost-sensitive projects Engineering conclusion:If maintenance is frequent or shutdown is not feasible, then a blind valve with inline operation capability should be prioritized. 3. Mechanical Reliability The reliability of a blind valve does not depend on complex sealing systems, but on: ● Mechanical structural stability ● Material strength (such as A105, WCB, F22, LF2) ● Actuation method (manual, gear-operated, or hydraulic) ▶ If the service conditions involve high temperature, high pressure, or corrosive media, then sealing-based valves are more prone to failure▶ If...
Choosing the right industrial valve type is one of the most critical decisions in system design. A poor selection—even when using high-quality valves—can lead to leakage, pressure loss, vibration, frequent maintenance, and long-term operational inefficiency. This guide covers the main industrial valve types, their applications, advantages, and limitations, along with practical insights to help you make the right valve selection for your project in 2026. What Are Industrial Valve Types? Industrial valve types refer to different valve designs used to control, regulate, or isolate fluid flow in piping systems. Each type is engineered for a specific function—such as shut-off, throttling, or backflow prevention—and selecting the correct type is essential for system safety and efficiency. 5 Main Industrial Valve Types and Their Applications 1. Ball Valve Best for: Quick shut-off and low pressure drop Ball valves use a rotating ball with a straight-through bore. When fully open, they provide minimal resistance, making them one of the most efficient options for fluid transmission. Common applications: ● Oil and gas pipelines ● High-pressure systems ● Frequent on/off operations Selection notes: ● Full-port designs minimize energy loss ● Metal-seated ball valves perform better in abrasive or high-cycle conditions Avoid if:Precise flow control is required. Throttling with a ball valve can damage sealing surfaces over time. 2. Gate Valve Best for: Isolation service with minimal flow resistance Gate valves operate by lifting a gate out of the flow path. They are widely used in large-diameter pipelines where full open or full close operation is required. Common applications: ● Long-distance transmission pipelines ● Water treatment systems ● High-temperature steam lines Selection notes: ● Near-zero pressure drop when fully open ● Wedge gate valves provide better sealing in high-temperature conditions Avoid if:Frequent operation or throttling is required. Gate valves are not designed for repeated cycling. 3. Globe Valve Best for: Precise flow regulation Globe valves force fluid through a controlled flow path, allowing accurate throttling and stable flow control. Common applications: ● Steam systems ● High-temperature processes ● Flow regulation applications Selection notes: ● Excellent throttling performance ● Stable operation under fluctuating flow conditions Avoid if:Pressure drop must be minimized. Globe valves inherently create higher flow resistance. 4. Check Valve Best for: Automatic backflow prevention Check valves operate automatically based on flow directi...
Recently, Dervos Valve helped a client in Hungary overcome a common challenge in industrial steam systems: how to safely isolate high-temperature pipelines without leakage or downtime. Operating with saturated steam at around 250°C and exposed to temperatures as low as -39°C, the client’s system demanded a solution that was both robust and reliable. Traditional valves often failed to maintain a tight seal under such conditions, and conventional isolation methods required depressurizing the line, increasing downtime and operational risk. To address these challenges, Dervos supplied a DN400 PN40 sliding line blind valve, engineered specifically for the project’s harsh conditions. The valve’s sliding blind mechanism allows operators to switch between flow and isolation positions without depressurizing the system, enhancing safety and efficiency during maintenance. Built with forged 20GML steel and a metal-to-metal stainless steel sealing structure, the valve delivers reliable performance under both high-temperature steam and extreme outdoor climates. Its full-bore design minimizes flow resistance, while the worm gear manual actuator ensures smooth and controlled operation even at large sizes and high pressure ratings. Safety features such as anti-misoperation devices and protective blind plate structures further reduce the risk of errors during handling. Since installation, the valve has enabled leak-free operation, safer maintenance procedures, and stable performance in extreme temperatures. Designed for a service life exceeding 30 years, it provides a long-term, low-maintenance solution, giving the client confidence in their steam system’s reliability and safety. This project highlights how a carefully engineered sliding line blind valve can solve critical isolation challenges in high-temperature steam applications, combining operational safety, durability, and efficiency in one solution.
The swing check valve is made of A216, a kind of WCB. Manufactured according to BS1868, the check valve is 6 inch and 150LB. And the valve is capable in working temperature between -19 to 425 degree Celsius.
Payment:
30% when order confirmed, 70% before shipmentProduct Origin:
ChinaColor:
CustomizationShipping Port:
Shanghai, ChinaLead Time:
30~60 days Ex Works after order confirmationMaterial:
WCBMethod of Operation:
NonQuick Detail
|
Type |
Check Valve |
|
Size |
6'' |
|
Design Pressure |
Class 150 |
|
Construction |
Swing Type |
|
Connection |
RF |
|
Design & Manufacture |
BS 1868 |
|
End to End |
ASME B16.10 |
|
Connection |
ASME B16.5 |
|
Test & Inspection |
API 598 |
|
Body Material |
A216 WCB |
|
Temp. |
-29~425 ℃ |
|
Media |
W.O.G. |
Features
1.BB: bolted bonnet
2.Swing type disc
3.Full/Reduced bore design
4.Superior flow rates
5.Minimized friction loss
6.Standard trim material for selection
7.External or internal hinge pin available on request
8.Cylinder and counter weight available on request
9.Bare stem and actuators are available on request
Technical Drawing
Coat Thickness Check
Dervos Packaging
Based on sufficient experience, we have developed complete packing specifications and procedures to ensure clear and safe transportation so that you can receive good and sound products. And this is also an important factor that we earn good reputation from our customers.
About Dervos
Xiamen Dervos Valves Industry Co.,Ltd (stock code 861601), founded in June 2008, is a one-stop industrial valves supplier integrated of R&D, manufacture, resource integration, and trade service. For 12 years, Dervos has been committed to finding solutions for industrial needs and providing professional service for both general and specialized valves.
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The 8 inch non return check valve conforms to BS 1868 design code, with bolted bonnet and swing type disc. The flanged check valve is made of carbon steel A216 WCB. Design Feature 1.BB: bolted bonnet 2.Swing type disc 3.Reduced bore design 4.Superior flow rates 5.Minimized friction loss 6.Standard trim material for selection 7.External or internal hinge pin available on request 8.Cylinder and counter weight available on request 9.Bare stem and actuators are available on request Quick Detail Type Check Valve Size 8'' Design Pressure ANSI 1500 Construction Bolted Bonnet, Swing Type Connection Raised Face Flange Design & Manufacture BS 1868 End to End ASME B16.10 Connection ASME B16.5 Pressure & Temp ASME B16.34 Test & Inspection API 598 Body Material Carbon Steel Applicable Temp -29℃~+400℃ Media W.O.G. Dimension Class 1500 NPS in 2 2 1/2 3 4 6 8 10 12 DN mm 50 65 80 100 150 200 250 300 L-L1 (RF-BW) in 14-1/2 16-1/2 18-1/2 21-1/2 27-3/4 32-3/4 39 44-1/2 mm 368 419 470 546 705 832 991 1130 L2 (RTJ) in 14-5/8 16-5/8 18-5/8 21-5/8 28 33-1/8 39-3/8 45-1/8 mm 371 422 473 549 700 841 1000 1146 H (OPEN) in 12-1/4 12-1/4 13 14 15-3/4 20-7/8 22-1/16 25-5/8 mm 310 310 330 355 400 530 560 650 WT (kg) RF 69 93 140 232 490 990 1490 1970 BW 49 74 111 185 375 803 1250 1625
The swing type check valve, designed with PN40 RF flange, bolted cover, is made of cast steel 1.0619 and ss316 trim material. The full bore check valve can be manufactured per client's special requests. Quick Detail Type Non Return Valve ( Check Valve) Nominal Size DN 150 NominalPressure PN 40 Construction BB, Swing Type Disc, Exnternal Pin Connection Raised Face Flange Design & Manufacture DIN 3356 End to End EN 558 Connection EN 1092 Test & Inspection EN 12266 Body Material GS-C25 (1.0619) ApplicableTemp -29℃~+425℃ Media W.O.G. Material No Part Name Carbon steel to ASTM Alloy steel to ASTM Stainless steel to ASTM WCB LCB WC6 WC9 C5 CF8 CF8M CF3 CF3M 1 Body A216 WCB A350 LCB A217 WC6 A217 WC9 A217 C5 A351 CF8 A351 CF8M A351 CF3 A351 CF3M 2 Seat Ring A105 A350 LF2 A182 F11 A182 F22 A182 F5 A182 F304 A182 F316 A182 F304L A182 F316L 3 Disc nut A182 F304 A182 F304 A182 F316 A182 F304L A182 F316L 4 Disc washer A182 F304 A182 F304 A182 F316 A182 F304L A182 F316L 5 Disc A216 WCB A350 LCB A217 WC6 A217 WC9 A217 C5 A351 CF8 A351 CF8M A351 CF3 A351 CF3M 6 Hinge A216 WCB A350 LCB A217 WC6 A217 WC9 A217 C5 A351 CF8 A351 CF8M A351 CF3 A351 CF3M 7 Hinge pin A182 F304 A182 F304 A182 F316 A182 F304L A182 F316L 8 Yoke A216 WCB A350 LCB A217 WC6 A217 WC9 A217 C5 A351 CF8 A351 CF8M A351 CF3 A351 CF3M 9 Bonnet nut A194 2H A194 4 A194 7 A194 8 10 Bonnet bolt A193 B7 A193 L7 A193 B16 A193 B8 11 Gasket Stainless Steel Spiral Wound graphite or Stainless Steel Spiral Wound PTFE 12 Cover A216 WCB A350 LCB A217 WC6 A217 WC9 A217 C5 A351 CF8 A351 CF8M A351 CF3 A351 CF3M 13 Hook screw Steel 14 Name Plate Stainless steel or Aluminum 15 Rivet Stainless steel or Aluminum Other Material ( Alloy 20, ANSI 321, Monel Hastelloy, etc)are available on request Our Service A good customer service is as valuable as product itself. In Dervos, we will offer a full range of customer service to make you feel easy when doing business with us. Providing weekly production report When production begins, you will get production report weekly, so that you can have good command of product status and report to your customer at the meantime. Offering warranty of 18 months 18 months warranty period will be offered after shipment, no concern to purchase valve from Dervos. Providing solutions within 3-days for complaints All the complaints will be solved within 3 days, in this case, you can timely reply and solve problems for your customer, to relax them even when complaints happening.
The stainless steel CF8 non return valve features in non slam type disc, ANSI 150 flange end, and full port design. Quick Detail Type Non Return Valve ( Check Valve) Size 8'' DesignPressure Class 150 Construction Non Slam Type Connection RF Flange Design & Manufacture ASME B16.34 End to End ASME B16.10 Connection ASME B16.5 Pressure & Temp ASME B16.34 Test & Inspection API 598 Body Material A351 CF8 Trim Material SS304 Media W.O.G. Available Modifications for Dervos Valves -Valve Pressure -Valve Size -Reduced Bore & Full Bore -Body & Trim Material (Disc, Seat, Pin, Spring) -End Connection (Flange, BW, SW, Thread, Wafer, Lug) -Available Operation (Bare Stem, With Actuators) -Available Counterweight -Available Cylinder -Customizing Coating -Customizing Packaging Related Knowledge What is non-slam check valve? Water hammer is a hydraulic phenomenon that undergoes an abrupt change in its rate of flow and are caused by sudden shutting or slamming. Water hammer will reduce process efficiency, cause valve damage, gasket joint leaks and other problems. The non-slam check valve is designed to reduce water hammer. An internal spring can prevent the disc from slamming close.The design of a non-slam check valve could eliminate pressure flutuations, vibration and damges. Plus, the disc and spring experience minimal wear over time, which will largely extend the service lives of non-slam check compared to swing check valve.
API6D swing type check valve RF connnection bolted bonnet full pore WCB body, WCB+13Cr disc, A105+13Cr seat ring, WCB hinge. Suitable temperature in -29℃~+425℃ Quick Detail Type Swing Check Valve Size 4 inch-6 inch Design Pressure CL600 Construction BC, Swing type ConnectionType Flange OperationType - Body Material WCB DiscMaterial WCB+13Cr Hinge Material WCB Seat Material A105+13Cr Design Code API 6D Face to Face Dimension ASME B16.10 Test and Inspect API 598 Pressure & Temp ASME B16.34 Medium Water, Oil and Gas Origin China
Chinese manufacturer Dervos offers 14 Inch swing check valves made according to API 6D. Other features cover CL300, RF End Connection, WCB body.
The swing check valve is made of 1.0619, a kind of carbon steel, as per DIN standard.The check valve is DN80 and PN40, or 3 inch and 300LB. And the valve is capable in working temperature between -19 to 425 degree Celsius.
The 1 inch swing check valve has the construction of bolted bonnet and RF flange end. The forged steel swing check valve is designed with reduced bore as per API 602. Dervos could also do customizing service as per clients’ requests on sizes, design ratings, materials, and standards and so on.
Made of high-quality casting, the DIN swing check valve has a cast steel body with bolted bonnet structure and flange connection. The valve is designed with good sealing performance and minimal water hammer effect.
DN400 PN10 check valve is made according to DIN standard. The valve body is made of WCB. It has the structural characteristics of swing type and structural length of 310mm. It has the connection mode of RF. This valve has a built-in damper, which is mainly used for shock absorption and energy dissipation.
6" 1500LB swing check valve is made according to API 6D standard. The valve body is made of WCB. It has the structural characteristics of swing type. It has BW connection mode.
1" 150LB swing check valve is made according to API 602 standard. The valve body is made of A105. It has the structural characteristics of bolt cover, swing type and full bore. Its connection mode is RF (Welded Flange).
6" 150LB check valve is made according to API 6D standard. The valve body is made of WCB. It has the structural characteristics of swing type and external pin. Its connection mode is RF.
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