The PVC diaphragm Back Pressure Valve is designed for chemical feed systems to maintain consistent dosage rates by applying back pressure to the metering pump and preventing siphoning. It eliminates the effects of varying downstream pressure. When the diaphragm exceeds the preset pressure of 50 psi, chemical flows through the valve to the injection point. The valve can be field-adjusted using the adjustment screw. To avoid chemical line drainage, it is recommended to install the valve as close as possible to the injection point. Additionally, it's important to ensure that all chemical system equipment, including pulsation dampeners and pressure gauges, are located between the pump and the valve.
Basic information of PVC Series Back Pressure Valves:
Diaphragms: PTFE / EPDM etc.
Material for valve body: PVC
Adjustable pressure: 0-1.0MPa
Connection type: Thread,Flange and can be customized
Model parameter of PVC Series Back Pressure Valves:
| Model | Material | Nominal Dia.（mm） | Setting Pressure(MPa) | Dimension | Standard connection | |
| Lower Valve Body Dia.(mm) | Total Hight(mm) | |||||
| RXBF-P6/1.0 | PVC | 6 | 0.1-1.0 | 64.7 | 82 | Rc1/8” |
| RXBF-P8/1.0 | PVC | 8 | 0.1-1.0 | 64.7 | 87 | Rc1/4” |
| RXBF-P10/1.0 | PVC | 10 | 0.1-1.0 | 64.7 | 89 | Rc3/8” |
| RXBF-P15/1.0 | PVC | 15 | 0.1-1.0 | 64.7 | 94 | Rc1/2” |
| RXBF-P20/1.0-N | PVC | 20 | 0.1-1.0 | 64.7 | 104 | Rc3/4” |
| RXBF-P20/1.0 | PVC | 20 | 0.1-1.0 | 87 | 123 | Rc3/4” |
| RXBF-P25/1.0 | PVC | 25 | 0.1-1.0 | 87 | 128 | Rc1” |
| RXBF-P32/1.0 | PVC | 32 | 0.1-1.0 | 117 | 175 | Rc1 1/4” |
| RXBF-P40/1.0-N | PVC | 40 | 0.1-1.0 | 117 | 185 | Rc1 1/2” |
| RXBF-P40/1.0 | PVC | 40 | 0.1-1.0 | 137 | 240 | Rc1 1/2” |
| RXBF-P50/1.0 | PVC | 50 | 0.1-1.0 | 167 | 260 | Rc2” |
| RXBF-P65/1.0 | PVC | 65 | 0.1-1.0 | 177 | 325 | Rc2 1/2” |
| RXBF-P80/0.6 | PVC | 80 | 0.1-0.6 | 230 | 420 | Rc3” |
| RXBF-P100/0.6 | PVC | 100 | 0.1-0.6 | 250 | 430 | Rc4” |
| Other unspecified model/material/connection and DN100 above can be customized according to requirement. | ||||||
The Back Pressure Valve functions as an anti-siphon valve, preventing liquid flow or siphoning due to gravity. Additionally, the valve can decrease flow due to siphoning and regulate pressure fluctuations. Anti-siphon valves only permit water to flow in one direction.
Design features:
- With Diaphragm structure spring and the pressure can be adjustable.
- The wetted parts are only the lower valve body and the diaphragm and they are assembled with sealing rib which has good sealing effect and high sensitivity.
- Multiple materials of diaphragm are optional to meet the usage of different environments and scenarios.
| Technical Parameters | |
| Connection type | Thread, flange etc. and can be customized |
| Adjustable pressure | 0-1.0MPa, 0-2.0MPa |
| Safety test pressure | 1.5 times the maximum input pressure |
| Applicable temperature | -60℃ to +300℃ (customizable） |
| Available materials | |
| Materials for Lower valve body | PVC,SS304,SS316L,Hastelloy, PTFE,PVDF,PP, carbon steel etc.and can be customized |
| materials for diaphragm | PTFE composite NBR,EPDM etc. |
| Material for upper valve body | Nylon,PVC, carbon steel , SS304,SS316L etc.and can be customized |
