A non-return check valve lets the medium pass through in one direction, where the medium opens (while passing the valve up-flow) as well as closes (when back-flow occurs) the valve. A number of aspects is essential during this process. The overruling objective of non-return valves is the prevention of water hammer and backflow. Hanwel delivers vales which satisfy these demands and which deliver optimal control.
Most pipeline systems require some form of check valve device to maintain flow in one direction to prevent either contamination of liquids already in the system or damage to the pipework and its ancillary components. Pumps, for example, can be secured by a non-return check valve against backflow after shut-down. Though it is generally thought that this function can easily be executed by relatively simple non-return check valves, this way of thinking often turns out to be costly. Dangers such as water hammer, with all its consequences, are to be ruled out as much as possible.
What are the check valve features that the piping engineer is looking for?
- Tight shut off under minimum back pressure.
- Quick response to no-flow or reverse flow conditions.
- Low resistance to forward flow.
- Lightweight construction.
- Ease of installation with unskilled operators .
- No maintenance.
- It is a stop silent valve.
- It stops the reverse flow and is completely silent in its operation, preventing “water hammer”.
Hanwel acknowledges the importance of these functions and we supply a broad range of non-return valves that all contribute to maximum process control. Besides, we gladly collaborate with you during new product development processes to offer the best solutions to your problems.
Northvale tilting disk
- Range: DN40 – DN1000
- Temperature: max. 525°C
- Pressure range: ANSI 150 / 300 en PN 16/25/40/100
- Available materials: Steel, SS 316 or other quality materials
Konrad check valves
- Double-eccentric: minimal friction/wearing
- Range: DN 100 up to DN 2000
- Temperature range: -196°C up to + 550°C
- Pressure: max. PN 63
- 100% gas and water tight, unidirectional or bidirectional
Lohse check valves
- Swing Check, disco and dual plate check valves
- Range: DN 15 / DN 600
- Temperature range: -10 ° C to + 30 ° C
- Pressure to PN 16
- Steel, stainless steel, bronze, duplex 1.4469
Norval membrane check valves
- Silent rubber membrane
- Range: DN 40 to DN 200
- Temperature range: 0°C to + 180°C
- Pressure to PN 16
- For mounting between flanges