Liquid medium back pressure valve

Liquid back pressure valveIt is a direct acting spring diaphragm type pressure stabilizing element designed specifically for precision fluid systems. Its core function is to provide constant back pressure for metering pumps, dosing systems, and chemical pipelines, suppress siphoning, eliminate pulsation, ensure flow accuracy and equipment safety, and is widely used in chemical, water treatment, pharmaceutical, food and beverage industries.

1、 Product positioning and core functions

Stable upstream pressure: provides constant back pressure for metering pumps/volumetric pumps to ensure accurate flow output

Anti siphon/anti backflow: automatically shuts off when the machine is stopped, avoiding self flow and backflow pollution of the medium

Overpressure relief protection: automatically opens when the pressure exceeds the limit, protecting pipelines and equipment

Eliminate pulsation: When used in conjunction with dampers, significantly reduce pressure fluctuations and water hammer

2、 Working principle

Adopting a spring diaphragm force balance structure:

System pressure<set value: The spring pre tension tightens the diaphragm, the valve closes, and back pressure is established

System pressure>set value: medium thrust overcomes spring force, diaphragm lifts, medium overflows

Pressure drop: The valve automatically closes to maintain stable set pressure

3、 Key technical parameters (universal type)

Structural form: direct acting, spring diaphragm type, internal thread connection

Nominal diameter: DN6/8/10/15/20/25

Pressure regulation range: 0.02-16 MPa (multiple pressure ranges are optional)

Control accuracy: ± 1 KPa

Applicable temperature: -30-328 ℃

Standard EPDM+PTFE composite membrane: -5 ℃ to+80 ℃

Pure PTFE membrane: -10 ℃~+120 ℃

Leakage level: Zero leakage (sealing level VI)

Connection method: Internal thread NPT/BSP, flange, quick install

Installation direction: Both vertical and horizontal are acceptable. It is recommended to install vertically

4、 Material selection (corrosion-resistant adaptation)

componentOptional materialsApplicable scenarios

valve bodyPVC/PP/PVDF/SS304/SS316LAcid base, organic solvents, clean fluids

diaphragmEPDM 衬 PTFE、 纯 PTFE、FKMStrong corrosion, high temperature, and hygienic working conditions

spring316L、 HastelloyHighly corrosive medium

sealEPDM、FKM、PTFETemperature resistant and corrosion-resistant matching

5、 Product technical advantages

High precision voltage stabilization: The diaphragm responds sensitively with minimal pressure fluctuations

Zero leakage seal: sealing rib+composite membrane structure, no internal leakage or external leakage

Maintenance free design: no vulnerable sliding parts, anti impurity, long service life

Wide medium adaptation: Available in all materials, compatible with strong acids, strong alkalis, slurries, and pure water

Easy to adjust and calibrate: Top knob for pressure adjustment, with locking and anti loosening features

6、 Typical application scenarios

Pressure stabilization at the outlet of the metering pump (improving metering accuracy)

Chemical dosing and acid-base transport system

Pure water/ultra pure water, food and beverage hygiene pipeline

Environmental water treatment, reverse osmosis, and chemical dosing

Laboratory precision fluid control

7、 Selection and installation points

Back pressure setting value: recommended to be 10% -30% of the system working pressure

Metering pump outlet: It is recommended to have a back pressure of ≥ 0.07 MPa to ensure accuracy

Installation position: Adjacent to the equipment outlet to avoid the impact of pressure drop in long pipes

Overflow port: can be connected to a reflux tank or low-pressure pipeline