Back Pressure Valves/Relief Valves for Low-Pressure Metering Pumps
Back pressure valves are used to generate a constant back pressure and achieve precise metering in systems with a free outlet. They are also used in conjunction with pulsation dampers to generate low-pulsation metering.
Product description
Backpressure, antisiphon and pressure relief valves
Backpressure (2-port) valves may be used in-line to provide a constant discharge pressure for protection from siphoning, or they may be teed off of the discharge line for pressure relief, discharging back to the source tank or to the pump suction line to create a bypass.
Pressure relief (3-port) valves are mounted in the discharge line, featuring a separate relief port which discharges back to the source tank or to the pump suction line to create a bypass.
Backpressure valves provide several functions: they improve repeatability by providing a constant discharge pressure; they provide antisiphon protection for discharge into pressurized water lines or vacuums, or where suction head exceeds discharge head; and they minimize pulsation when used in conjunction with a pulsation dampener.
In-line backpressure/antisiphon and pressure relief valves
These adjustable backpressure (2-port) and pressure relief (3-port) valves have FNPT ports and require tubing adapters for use with flexible tubing.
Can be adjusted with screwdriver.
Dimensions in inches (mm)
| A | B | C | D | E |
| 2.6 (65) | 1/4 NPT | 1.2 (31) | 4.9 (125) | 6.2 (158) |
| 2.6 (65) | 1/2 NPT | 1.2 (31) | 4.9 (125) | 6.2 (158) |
| 3.5 (88) | 3/4 NPT | 1.1 (28) | 5.4 (136) | 6.7 (169) |
| 3.9 (98) | 1 NPT | 1.4 (36) | 5.7 (145) | 7.0 (178) |
| 4.6 (118 ) | 1-1/2 NPT | 2.2 (56) | 9.0 (229.5 ) | 10.3 (260.5) |
| 4.6 (118 ) | 2 NPT | 2.2 (56) | 9.0 (229.5 ) | 10.3 (260.5) |
Multifunction Valve
Back pressure valve/relief valve for fitting directly on the pump's dosing head with the functions:
- Back pressure valve, opening pressure approx. 21.75 psi with free outlet or priming pressure at the suction end (black rotary dial)
- Relief valve, opening pressure approx. 87, 145 or 232 psi (red rotary dial)
- Priming aid for pending back pressure, no need to release discharge line
- Discharge line relief, e.g. prior to service work
The multifunctional valve is operated by free-moving rotary dials that automatically return to their original position when released by the operator. This means operation is possible even when access is difficult. The multifunctional valve is made of PVDF and can be used to meter almost any chemical.
Caution: Back pressure valves are not absolutely leak-tight shut-off devices! It is essential that you observe the installation notes in the operating instructions!
Caution: The bypass line should always be connected.
Materials in Contact with the Medium
| Valve body | PVDF |
| Diaphragm | PTFE-coated |
| Seal | FKM and EPDM (loose) |
Type | Relief opening pressure* | Connector size | Bypass connector | Dim. B | Dim. H | Order no. |
|---|---|---|---|---|---|---|
inch | inch | |||||
* The relief opening pressure given above is the pressure at which the valve starts to open. The pressure may be up to 50% more than this before the valve is fully open depending on the type of pump. | ||||||
Size I | 232 psi | 6-12 | 6 x 4 | 4.65 | 3.5 | 792011 |
Size I | 145 psi | 6-12 | 6 x 4 | 4.65 | 3.5 | 791715 |
Size I | 87 psi | 6-12 | 6 x 4 | 4.65 | 3.5 | 1005745 |
Size II | 145 psi | 6-12 | 12 x 9 | 5.43 | 3.78 | 792203 |
Size II | 87 psi | 6-12 | 12 x 9 | 5.43 | 3.78 | 740427 |
Size III | 145 psi | DN 10 | 12 x 9 | 5.43 | 4.72 | 792215 |
| Application: multifunctional valves | |
|---|---|
| Size I | ALPc 1001, 1002, 1004, 1008, 0708 |
| beta, type 1000, 1601, 1602, 1604, 1605, 1005, 1008, 0708, 0413, 0220 | |
| gamma/ X type 1602, 1604, 1009, 0708, 0414, 0220 | |
| gamma/ XL type 1608, 1612 | |
| Size II | ALPc 0417, 0230 |
| beta, type 1605, 1008, 0713, 0420, 0232 | |
| gamma/ X type 1009, 0715, 0424, 0245 | |
| gamma/XL type 1020, 0730 | |
| Size III | gamma/ XL type 0450, 0280 |
For material version PP, PV, NP, TT
Pressure Relief Valves
1/4" FNPT Backpressure Valves (2-port)
| Order no. |
|---|---|
PP | 1009444 |
PVC | 1009445 |
PVDF | 1009446 |
316 SS | 1009447 |
1/4" FNPT Backpressure Valves (3-port)
| Order no. |
|---|---|
PP | 1009452 |
PVC | 1009453 |
PVDF | 1009454 |
316 SS | 1009455 |
Tubing Adapters
(1 required per valve port): 1/4" x 3/16" tubing x 1/4" MNPT
| Order no. |
|---|---|
PP/EPDM | 7500060 |
PP/Viton® | 7500058 |
PVC/EPDM | 7500064 |
PVC/Viton® | 7500062 |
1/2" FNPT Backpressure Valves (2-port)
| Order no. |
|---|---|
PP | 1006846 |
PVC | 1006850 |
PVDF | 1006854 |
316 SS | 1008796 |
1/2" FNPT Backpressure Valves (3-port)
| Order no. |
|---|---|
PP | 1006858 |
PVC | 1006862 |
PVDF | 1006866 |
316 SS | 1008800 |
Tubing Adapters
(1 required per valve port): 1/2" x 3/8" tubing x 1/2" MNPT
| Order no. |
|---|---|
PP/EPDM | 7500061 |
PP/Viton® | 7500059 |
PVC/EPDM | 7500065 |
PVC/Viton® | 7500063 |
3/4" FNPT Backpressure Valves (2-port)
| Order no. |
|---|---|
PP | 1006847 |
PVC | 1006851 |
PVDF | 1006855 |
316 SS | 1008797 |
3/4" FNPT Backpressure Valves (3-port)
| Order no. |
|---|---|
PP | 1006859 |
PVC | 1006863 |
PVDF | 1006867 |
316 SS | 1008801 |
1" FNPT Backpressure Valves (2-port)
| Order no. |
|---|---|
PP | 1006848 |
PVC | 1006852 |
PVDF | 1006856 |
316 SS | 1008798 |
1" FNPT Backpressure Valves (3-port)
| Order no. |
|---|---|
PP | 1006860 |
PVC | 1006864 |
PVDF | 1006868 |
316 SS | 1008802 |
1-1/2" FNPT Backpressure Valves (2-port)
| Order no. |
|---|---|
PP | 1006849 |
PVC | 1006853 |
PVDF | 1006857 |
316 SS | 7302243 |
1-1/2" FNPT Backpressure Valves (3-port)
| Order no. |
|---|---|
PP | 1006861 |
PVC | 1006865 |
PVDF | 1006869 |
316 SS | 7302261 |
2" FNPT Backpressure Valves (2-port)
| Order no. |
|---|---|
PP | 1009448 |
PVC | 1009449 |
PVDF | 1009450 |
316 SS | 7302247 |
2" FNPT Backpressure Valves (3-port)
| Order no. |
|---|---|
PP | 1009456 |
PVC | 1009457 |
PVDF | 1009458 |
316 SS | 7302265 |
Spare Parts Sets
Contains 1 of each: compression spring, diaphragm, spring plate, and pressure adj. disc.
| Order no. |
|---|---|
SPK 1/4" - 1/2" | 1035446 |
SPK 3/4" - 1" | 1035447 |
SPK 1-1/2” - 2" | 1035448 |
Spare Diaphragms
| Order no. |
|---|---|
1/4" - 1/2" valve PTFE/EPDM | 1006813 |
3/4" - 1" valve PTFE/EPDM | 1006814 |
1-1/2” - 2" valve PTFE/EPDM | 1006815 |
High pressure relief valve, adjustable, 1/4" and 1/2" NPT for Sigma X, Makro HK and ProMus pumps
Can also be used as a backpressure valve for < 30 gph (113 l/h).These valves are without springs, which must be ordered separately.
Connector size | Order no. | |
|---|---|---|
Stainless steel/Viton® | 1/4" NPT male and female thread | 7202505 |
Stainless steel/EPDM | 1/4" NPT male and female thread | 7744507 |
Spring counter pressure min. | Spring counter pressure max. | Spring colour | Order no. |
|---|---|---|---|
psi | psi | ||
49 | 348 | blue | 7202519 |
348 | 754 | yellow | 7202520 |
754 | 1,494 | violet | 7202525 |
1,494 | 2,248 | orange | 7202524 |
2,248 | 3,002 | brown | 7202523 |
3,002 | 4,003 | white | 7202522 |
4,003 | 5,004 | red | 7202521 |
Connector size | Order no. | |
|---|---|---|
Stainless steel/Viton® | 1/2" NPT male and female thread | 7744508 |
Stainless steel/EPDM | 1/2" NPT male and female thread | 7744509 |
Spring counter pressure min. | Spring counter pressure max. | Spring colour | Order no. |
|---|---|---|---|
psi | psi | ||
49 | 348 | blue | 7744510 |
348 | 725 | yellow | 7744511 |
725 | 1,450 | violet | 7744512 |
Overview
Accurately metered
Back pressure valves are designed for different applications. Please refer to the relevant notes for the different designs.
Relief valves are used in the bypass to protect pumps, pipes and fittings from overpressure in the event of incorrect operation or blockages. In the event of a malfunction, the pump pumps back into the storage tank.
The benefits for you
- Protects against overpressure
- Priming aid
- Relieves the pressure line
- Increases dosing precision