Special valves & tank safety systems
VARIVENT® Safety valves
VARIVENT® Safety valves were specially developed for the food, beverage, and pharmaceutical industries and meet all the relevant standards and regulations such as DIN 11866 or ASME BPE. With a low deadspace inlet area, the unique LESER HyTight assembly, and the optional pneumatic lifting device you have very good cleanability (CIP, SIP). With a large selection of aseptic connections (threaded, flanged, or clamped) the valve can be optimally fitted to different requirements.
Function
Full-life safety valves open pop action so that it is possible to release high mass flow rates or quick occurring pressures. They are often used in steam or gas applications. These valves open completely even at small pressure rises and can therefore discharge the full mass flow.
Normal stroke safety valves are optimal pressure relief valves. They have got a wide proportional area so that they steadily activate during pressure relief and pressure peaks. Their long proportional phase have nearly full-life character. These similar properties can reduce big mass flows. They are also used as overflow valves and when smaller sizes of full-life safety valves are still to big.
To guarantee that all product touched surfaces can be cleaned hygienically (CIP) or sterilized (SIP) it is possible to get the valves with optional pneumatic lifting device.
Characteristic Features
- High-quality materials and surface finish
- Manual or pneumatic lifting device
- Insensitive to temperature
- Welded housings in CIP-able design
- Pocket free and drainable housing design
Application Examples
Safety valves prevent tanks against overpressure for example vessels within a sterilization process or during tank filling. They protect fermentation tanks prior damages in case of unexpected disturbance.
Normal stroke safety valves are optimal pressure relief valves. They have got a wide proportional area so that they steadily activate during pressure relief and pressure peaks. Their long proportional phase have nearly full-life character. These similar properties can reduce big mass flows. They are also used as overflow valves and when smaller sizes of full-life safety valves are still to big.
Safety valves are installed for pressure relief to secure intactness of vessels and other process equipment when media gets solid like chocolate.
HyTight Assembly
Very good cleanability - this is the requirement for the design of the LESER Clean Service safety valves. These valves are equipped with the HyTight Assembly which offers optimal cleaning possibilities.
The HyTight Assembly with its elastomer bellow covers all parts which are difficult to clean against product contact. Please keep in mind that the elastomer bellow does not compromise counter pressure like stainless steel bellows.
Lifting Devices
Safety valves of the VARIVENT series have got gas sealed lifting devices of the valve disk. This design makes enables the lifting of the valve disk during pipe cleaning to clean all inner parts including seat area and O-Ring. There are either manual as well as pneumatic lifting devices available.
Full-life Safety Valve, Type 488
The Safety Relief Valves series 488 were developed in close cooperation with plant owners and engineers. They reliably protect process plants from overpressure without putting hygienic requirements at risk. The whole series has been designed and officially approved according to international standards (DGR 97/23/CG, ASME, GOST, etc.).
A variant for steam, gas and liquid of each valve has been type-tested by TÜV in accordance with German regulations. They comply with the EU directive for pressure equipment and bear the CE symbol. The VARIVENT(R) Safety Valve Type 488 fulfills the special cleaning and performance abilities which are required for the food, brewery und beverage industry. It has a wide performance area so that is very good applicable for large plants.
