Stafsjö broaden its product range with the new HL valve

– The HL valve represents the first step in our new “Slim line” consisting of compact versions of Stafsjö’s existing product range. Driving forces have been ongoing continuous cost reduction program combined with market driven factors, especially when we are expanding into new business segments. The HL will broaden our product range in high and low pressure applications where we ensure reliability, low cost of ownership and customer satisfaction, says Thomas Carlson, CEO of Stafsjö.

Product features

Stafsjö’s knife gate valve HL is bi-directional and tight in both pressure directions. It is a full bore valve with excellent flow characteristic. HL is equipped with a through-going gate for secure shut-off of static and high concentrated media, often a problematic duty for traditional valves. HL is developed for severe operating conditions with pulp, caustic liquor, reject and waste, but it is also suitable for other applications with powder, slurry and ash.

HL has a two piece valve body in stainless steel with purge ports and integrated guiding pads. PTFE body gaskets gives a secure sealing between the body halves. The valve is equipped with a gate in stainless steel and removable retainer rings which simplifies the change of seats. The valve is modular designed meaning that it can easily be customized with gate, seats and box packings according to media and requirements, as well for actuators and accessories.

Sealing principle

When the valve is fully open the bore is practically entirely free from cavities and as a consequence flow characteristic is excellent. In this position the two seats are protected by the retainer rings and the gate, preventing media from entering the valve body.

When the valve is operated from opened to closed position, the valve body, gland boxes and the seats gives the gate continuous support for reliable and secure shut-off. Internal guiding pads make this operation smooth and easy. When the valve closes some media can enter the valve body, but it is returned to pipe line when the valve is operated to open position. Stafsjö’s unique gland box packing, TwinPack™, gives a secure sealing where the gate exit the valve body and assures that no media reaches surrounding environment.