Through Gate Valve; First came the Through Gate design, which was able to accommodate higher consistencies of fiber in water, but had issues with through leakage and consistently released large amounts of fugitive emissions.

The was the first design to consider the effects of corrosive materials. The design featured a protective corrosion resistant body liner, but couldn’t perform low pressure uni-directional general purpose isolation.

• The Push-Through design emerged, enabling knife gates to handle high solid slurries. However, its more robust design still struggled due to releasing discharge on each and every stroke.
• Guided-Shear Gate ValveA true zero leakage bi-directional higher pressure design, known as the Guided-Shear Gate, featured the first true “knife” gate able to handle clean, clear or heavy slurry in highly alkaline or acidic solutions.

Severe Service Knife Gate Valve (SSKGV)

• In 2017, DSS Valves officially entered the market, boasting the most technologically advanced Severe Service Knife Gate Valve. The design completely removes the chance for fugitive emissions, surpasses the rigorous standards for Severe Service defined by the MSS, and provides bi-directional Zero Leakage to ASME/ANSI Class 600 (100 Barg).

The Six Key Factors;

• SSVs are not always the right valve for the application.
• General purpose valves can work. However it’s important to identify and understand these six key factors first to be sure.

Factor 1: Cycling

How often your valve is required to open and close plays a factor in deciding what type of valve you should.

• Frequent cycling can wear a valve out faster than you think. However, infrequent use can be just as concerning.
• Valves can seize and fail to operate when they remain open or closed for extended periods of time.

DSS Solutions for Cycling

• Dual transverse seal is standard
• Fully guided shear gate
• Larger Acme Screw
• SAE 660 bronze ACME nuts for smoother operation