DERVOS Valve Specialist
Positive Isolation Line Blind Valves — Manual & Actuated Solutions
Manufacturer and supplier of line blind valves for absolute positive isolation — sliding and swing types from 1" to 48", Class 150 to 1500.
Line Blind Valve Types
Two main line blind valve families — sliding type and swing type — each with specialized sub-types for your isolation requirements.
Featured Products
Line blind valves from DERVOS product catalog
1" - 48" Class 150 - 2500 Line Blind Valve ASME B16.34
Size: 1"–48" (DN25–DN1200)
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8" Class 150# Line Blind valve ASME DIN ISO Carbon Steel
Description: Standard
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ASME B16.34 10" 150LB Line Blind Valve, RF Connection, Body A105, Worm Gear Operated
Type: Line Blind Valve
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DN50 CL150 High Temperature Cam-Slide Line Blind Valve Stainless Steel
Description: Standard
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F11 Swing Type Blind Valve for Industrial Steam Systems | Cost-Effective Isolation
Type: Swing-Type Blind Valve
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Forged Slide Blind Valve DN400 PN40 LF2, EN12516-1/2 for Steam Service
Type: Slide Blind Valve
View details →Latest Knowledge
Technical articles about line blind valve selection, safety, and applications
How Does a Spectacle Blind Valve Differ from a Paddle Blind?
In refinery turnaround work, pipeline isolation is often treated as a routine maintenance task until operators face leakage during hot work preparation or line intervention. Choosing between a spectacle blind valve and a paddle blind is not simply a matter of installation preference. The selection a...
Read article →Line Blind Valve Installation Mistakes to Avoid
Common installation mistakes involving depressurization, flange alignment, sealing surfaces, torque, temperature, supports, and leakage testing, with guidance for reliable positive isolation.
Read article →DVS Sliding Blind Valve Achieves Zero Leakage and Positive Isolation for South African Oil Client in Multi-Media Pipelines
**Customer Challenge: Seal Failure and Lack of Positive Isolation During Frequent Multi-Media Switching**
Read article →Why DERVOS Line Blind Valves?
100% Positive Isolation
Solid blind plate physically blocks media — no reliance on soft seals alone.
On-line Isolation
Valve remains installed in the live system; isolation is performed at the valve location after local depressurization, without draining the entire pipeline.
Visible Position
External indicator shows open or blind position — reduces misoperation risk.
Custom Engineering
Sizes 1"–48", Class 150–1500, carbon/stainless/alloy materials, multiple actuators.
Certifications
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