Schroeder – SSV Automatic Recirculation ValveEnquire Now
The SSV Automatic Recirculation Valve (AR Valve) often referred to as Leak Off Valve at Eskom, is a reliable pump protection valve that automatically provides protection for high pressure multi-stage centrifugal pumps. Damage can occur during dry running or during low load / low flow operation. Overheating, wear, cavitation to total loss and severe damage, are some of the signs that you need an automatic recirculation valve.
“Reliable Pump Protection”
Generally suitable for pressures up to 140 bar (SSV18) or up to 180 bar (SSV19). As soon as the main flow falls below the required minimum flow as stipulated by the pump manufacturer, the AR Valve bypass opens to the extent that the required pump minimum flow is bypassed even if the main flow is zero. The pressure in the bypass is reduced via an integrated throttle line with a bypass non-return valve. The SSV series 10, 11 and 12 work with pressure reduction in the bypass by throttles only.
The AR Valve is flow-controlled, i.e. the non-return cone that controls the bypass via a lever, is raised solely by the main flow into a specific position. Increasing main flow raises the cone and decreasing main flow lowers the cone position. The cone reaches its top end position at operation flow. Via the lever, the non-return cone actuates the rotary valve in the bypass. When the cone is on its seat, the bypass valve is fully open.
By opening the bypass line, the increasing main flow lifts the cone and the bypass is closed simultaneously. The valve is a modulating design, i.e. it allows just as much liquid to flow through the bypass as is necessary to supplement the required minimum flow rate of the pump. The addition of main and bypass flow rate is always the required pump minimum flow. As soon as the main flow rate exceeds the pump minimum flow, the bypass is closed. Vice versa, the bypass is opened again when the main flow falls below the minimum flow.
In addition this purely mechanical device does not require external power or any kind of control unit, thus ensuring low operating costs and low Total Cost of Ownership (TCO). Eskom, Sasol, Sulzer, KSB, Weir, Flowserve and many others rely on Schroeder to protect their high value multi-stage boiler feedwater and process pumps.
Automatic Recirculation Valve – The All Rounder
25mm to 600mm / 1” to 24”
PN 10 – 400 / ANSI 150 – 2500
|Temperatures||-250°C to 400°C|
Carbon steel / Stainless Steel Other materials on request
|Forged stainless steel / Hardfaced / Stellited|
|Options & |
For protection of multi stage centrifugal pumps during minimum flow conditions by preventing overheating, excessive noise, instability and cavitation. Ideally suited for the protection of boiler feedwater pumps.