About DFT Check Valves

DFT^® Spring Assisted Silent Check Valves Prevent Water Hammer Problems

DFT^® silent check valves are known around the world as the valve to use to prevent or eliminate water hammer problems. Whatever your size, pressure or piping configurations, DFT^® has a check valve for you.
DFT^®products solve check valve problems and prevent check valve failures. DFT^® check valves meet specialized customer requirements, as opposed to simply meeting line size. In some cases, minor modifications to DFT^® valves have solved customer problems by improving performance and extending service life. The “Check Valve Doctor” continues to grow from satisfying these needs.

DFT^® In-Line Check Valve Features

• Designed to prevent “Water Hammer”: Spring-assisted, in-line design insures that as the forward flow in a pipeline decreases, the disc begins moving closer to the seat. By the time the flow stops, the disc is closed against the seat, preventing flow reversal. This prevents the valve from slamming closed, causing “Water Hammer” and the resultant noise and damage to piping systems from occurring
• Designed to open at 0.5 psi differential pressure and fully open at 1.0 psi differential pressure
• Can be installed in ANY position: Including vertical with flow up or down. (Special springs may be required)
• MSS SP 126-2000 Steel In-Line Spring-Assisted Center Guided Check Valves Standard: DFT^® carbon steel, stainless steel and alloy valves meet this standard. (Does not apply to the Basic-Check^®, Restrictor Check or Vacuum Breaker)
• Meet or exceed MSS SP-61 leakage requirements: Metal-to-metal seating is standard in all DFT^® in-line check valves. Cast iron valves meet AWWA seat leakage requirements
• Available with soft seats for bubble-tight shutoff
• Dual guided stems: The stem is guided upstream and downstream to guard against vibrations and insure proper disc seating. (Does not apply to the Basic-Check^®, DLC^®, Restrictor Check, SCV^® or Vacuum Breaker)
• Custom sizing available: The following DFT^® check valves can be sized to the appropriate flow conditions: Excalibur^®, GLC^®, WLC^®
• Pulse-Damping Design: the DFT^® Model PDC^® is specifically designed for use on the discharge of reciprocating air or gas compressors. The design includes a pulse-dampening chamber to protect against premature seat wear due to chattering
• Liquids, gas or steam: All DFT^® in-line check valves provide positive shutoff for applications involving liquids, gases or steam and can be used in most industries including oil and gas, petrochemical, pulp and paper, textiles, food and beverage and commercial construction. Applications include chemical lines, fluid injection, condensate recovery, steam, nitrogen, pump and compressor discharge, chiller and boiler feed systems. Cast Iron valves are recommended for liquid services only.
• Maintenance and Installation guides: Available for all DFT^® in-line check valves.

DFT^® Check Valves: