The back pressure valve is also called the pump protection valve. It is used in working conditions where the general control system cannot be applied. As a special pressure control valve, it is often matched with automatic recirculation and used in the pump protection system. Back pressure valves are also widely used in other control valve systems. The back pressure valve controls the upstream pressure to reach the pressure value set by the factory process or the pressure value required by the system to prevent vaporization and cavitation. Carefully match the process conditions between the automatic recirculation valve and the back pressure valve to ensure that the pump is optimally protected and provide a guarantee for the long-term stable and safe operation of the system.
If the back pressure valve is installed in the pump outlet mainline, the back pressure setting pressure must not exceed the pump-rated working pressure.
| FAILURE | REASON | SOLUTION |
| Insufficient back pressure | Improper back pressure adjustment | Adjust the set pressure by turning the adjusting nut, turning clockwise the pressure increases, and turning counterclockwise the pressure decreases. |
| There may be impurities between the valve base and the diaphragm | Disassemble, clean carefully, reassemble, and then adjust. | |
| Can’t bear the pressure after the spring is compressed | There may be impurities between the valve base and the diaphragm | Disassemble, clean carefully, reassemble, and then adjust. |
| Leakage under low pressure | The PTFE sealing surface is hard and the sealing effect is not good | If the medium does not corrode the EPDM rubber, the EPDM rubber can be installed downward as a sealing surface. |
| There may be impurities between the valve base and the diaphragm. | Disassemble, clean carefully, reassemble, and then adjust. | |
| Excessive back pressure | Improper back pressure adjustment | Turn the adjusting nut to adjust the set pressure, and turn counterclockwise to decrease the pressure. |
| Liquid leaking from the vent of the upper valve body | Ruptured or torn diaphragm | Remove and replace all damaged parts. Be sure to remove internal impurities before replacement. |