Since
1942
1942
Non-return valves
Check valves from the manufacturer up to 16 bar for liquid and gaseous media with rubber diaphragms made of EPDM, silicones, fluorosilicones, nitrile, NBR, fluorocarbon, Viton® and fluorosilicones.
Technical features of our check valves
Lasso Technik AG check valves are equipped with an elastomer diaphragm that prevents the back flow of liquid and gaseous fluids. The particularity of this membrane is its silent and gentle closing (without water hammer). The non-return valve provides a high and reliable diaphragm seal, even in the presence of granulated fluids (sandy water). In addition, our check valves act as a raw filter and protect pumps and systems. Our devices do not contain any mechanical or electronic moving parts likely to wear out, which guarantees a long service life.
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Non-return valves - Functions and applications
Diaphragm check valves
Stop Silent diaphragm check valves close gently and quietly and are therefore installed in residential buildings. Depending on the application, Stop Silent rubber diaphragms are available in different materials.
Cone check valves
Our Stop Silent® cone check valves feature a stainless steel valve cone and soft rubber diaphragm. These check valves guarantee a controlled flow direction and reduce the hammer effect to a minimum.
Reservoirs case study: non-return valves for water supply
In the water supply, the flow direction is defined by check valves. Also for accurate water measurement, this is important for water suppliers to rely on the reliable StopSilent preventer’s valves.
Foot valves for Pumps
StopSilent® as a foot valve is often adapted to customer requirements in order to minimize pressure loss. The fine membrane as a sealing element provides additional operational safety.
Non-return valves in the food industry
Stop Silent® valves in the production lines with pasty media, Stop Silent® is characterized by its simple design. In particular compared to mechanical valves, the elastomer diaphragms do not stick and wear out. And this makes Stop Silent® reliable.
Non-return armatures in process engineering
In the process engineering production plants, StopSilent ensures the direction of rotation and makes it possible to mix dangerous media.
Further areas of application for our non-return valves
- Water treatment
- Petrochemical installations
- Chemical apparatus and plant construction
- Heating installations
- Sanitary facilities
- Groundwater pumps
- Fittings
- Compressed air systems
- Pneumatic systems
- Solar technology
- Cooling water systems
- Ventilation valves and systems
- Foot valves
- Water and flow meter
- Irrigation systems
- Air conditioning
- Washing machines
- Technik process
- Fire hydrants
Diaphragm materials of the non-return valves
Stop Silent check valves are equipped with a diaphragm made of materials that are defined according to its application.
- Silicone membrane check valves (VMQ) for drinking water and food industry can be used at air temperatures up to +210°C, and water temperatures up to +100°C with a cold resistance up to about -55°C / -60°C.
- Non-return valves with ethylene propylene diene (EPDM) rubber membranes for cold and hot water, also suitable for short periods under steam for food sterilization.
- Nitrile rubber diaphragm check valves (NBR) for use in the petrochemical industry, solar technology and thermal coupling pumping systems.
- Viton® fluorocarbon diaphragm check valves for applications in the chemical industry. Has good resistance to acids and excellent resistance to low and high temperatures from -20°C to +220°C.
- Fluorosilicone membrane check valves (FVMQ) have very high heat and cold resistance and excellent resistance to weathering, ageing and ozone.
Installation examples of non-return valves
Simple and quick assembly of the non-return valve, the diaphragm is fixed in the perforated support cone and its sealing lips are placed on the inside surface of the cone. When the pressure increases in the direction of flow, the diaphragm deforms and allows the fluid to pass through. If the flow rate is reduced, the diaphragm returns to its initial position and closes the valve.
Check valve AS NU - DN 25 to DN 100
The AS NU check valve with minimum diameter flange designed to be mounted in a body, calibrated for installation in industrial and sanitary fittings. Sealing is achieved by a seal placed between the body and the edge of the flange.
Check valve AS 41 - DN 25 to DN 200
The AS 41 check valve is used, among other things, in standard flat-sealing screw connections.
Check valve AS 54 - DN 40 to DN 200
The AS 54 check valve is a quick and inexpensive solution that can be retrofitted without modifying the structure that houses the system.
Check valve SFL Flange - DN 40 to DN 200
The SFL check valve with flange is installed in flange bodies with a diameter between 40 mm and 200 mm. The valve is supplied hot-dip galvanized with Rilsan or stainless steel coating.
Check valve MKV multiple plug - DN 150 to DN 600
The MKV multi-cone check valve is installed from 150 mm to 600 mm in diameter and is supplied with stainless steel or Rilsan coating. These valves can also be made entirely of stainless steel.
Download the complete Stop Silent information brochure:
News - Stop Silent
Installed then... forgotten!
In 1963, the water supply authorities of Lucerne (Switzerland) installed Stop Silent non-return valves. Since then, the valves have been doing their job: they make backflow impossible and thus prevent the risk of water contamination.
Lucerne Pumping Station - Water Supply
The highly appreciated Stop Silent valves from ...
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Case study: the hydrant connection of Aquaform Ltd. (Biel-Benken, Switzerland)
Aquaform Ltd. is a Swiss company producing "Rückflussverhinderer Typ EA". The fire brigades in other countries do not all use the same product. The equivalent or approximate translation would therefore be a valve used as a connection to the ...
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Check Valves - Technical Data
- Nominal pressure: 16 bar
- Temperature: -20° to +200°C (no steam)
- Speed: (fluids) 2.5 m/sec.
- Speed: (gases) 15 m/sec
- Dimensions: from DN 20 to DN 600
- Liquid: water, oils, acids and bases
Use and Stress Limits
- Pressure up to 16 bar
- Flow rate up to 15m / sec. (Gases) and 2.5 m / sec. (Fluids)
- Temperatures maximum 180 ° C (depending on pressure and diaphragm)
Contact Form
Use our contact form to send us all the information we need to process your request more efficiently.