Sanitary ball valves are widely used in the biopharmaceutical, food and beverage, cosmetics and other industries to control high-purity fluids (such as liquid medicine, dairy products, pure water, etc.). To ensure its long-term stable operation and compliance with hygiene standards, the following key points should be noted when using it:
1. Precautions for installation
(1) Inspection before installation
Cleanliness: The inner wall of the valve and pipe must be free of oil, dirt and particles. Rinse with pure water or alcohol before use.
Gasket/seal ring: Check whether it is intact, without damage or aging (such as EPDM, PTFE materials).
Flow direction mark: Confirm the flow direction of the medium of the ball valve (some valves have arrow marks).
(2) Installation method
Avoid stress: Do not force twisting or stretching when connecting the pipes to prevent deformation of the valve body.
Support and fixation: Long pipes need to add support frames to prevent the valve from bearing additional weight.
Welding connection:
If welding (butt-welded ball valve) is used, inert gas shielded welding (such as argon arc welding) must be used to prevent oxidation of the inner wall.
After welding, pickling and passivation are required to restore the corrosion resistance of the stainless steel surface.
Tri-Clamp connection:
Ensure that the clamp is evenly locked to avoid leakage caused by unilateral force.
The gasket should be made of food-grade EPDM or PTFE and resistant to high-temperature sterilization (such as SIP 121℃).
2. Operation precautions
(1) Switch operation
Manual operation:
Slowly rotate the handle (usually 90° switch) to avoid instantaneous high-pressure impact and damage to the valve seat.
It is forbidden to use an extended lever for forced operation to prevent the valve stem from deforming.
Pneumatic/electric operation:
Adjust the air pressure/voltage of the actuator to ensure that the switch is in place (some valves are equipped with limit switches).
Regularly check the stability of the air source to avoid the valve not being fully closed due to insufficient pressure.
(2) Avoid idling
Frequent switching of the ball valve in the absence of medium (dry running) will accelerate the wear of the seal. Make sure that the pipeline is filled with liquid before operation.
(3) High temperature/high pressure conditions
Steam sterilization (SIP):
Confirm that the valve material is temperature resistant (e.g. PTFE seals are limited to ≤150℃, EPDM ≤130℃).
Heating/cooling should be done slowly to avoid thermal shock causing seal failure.
High pressure system:
Check the valve rated pressure (usually PN10~PN16). Overpressure may cause the valve body to burst.
3. Maintenance and cleaning
(1) Regular inspection
Leak detection:
Check whether the valve stem packing (such as graphite packing) is leaking.
If internal leakage is found (the valve is not closed tightly), it may be due to wear of the valve seat or scratches on the ball, and the seal needs to be replaced.
Lubrication of moving parts:
Food-grade grease (such as NSF H1 certification) can be applied to the valve stem to prevent sticking.
(2) Cleaning (CIP/SIP)
Use 1%~2% NaOH or HNO₃ solution for cyclic flushing to remove residues.
After flushing, rinse thoroughly with pure water to avoid chemical residues.
In-situ sterilization (SIP):
Introduce 121℃ saturated steam and maintain for 20~30 minutes to ensure sterility.
After sterilization, cool slowly to prevent thermal deformation of PTFE seals.
(3) Long-term maintenance
Drain the liquid in the pipeline to prevent residual media from corroding the valve body.
The valve should be in a half-open state (45°) to avoid long-term compression deformation of the seal.
4. Selection and use taboos
(1) Selection points
Material: Valve body 316L stainless steel (Ra≤0.8μm), seal EPDM/PTFE/FKM.
Connection method: Tri-Clamp (quick release), welding (no dead angle), thread (non-critical pipeline).
Certification standards: FDA 21 CFR, EHEDG, 3-A Sanitary.
(2) Taboos in use
❌ Do not use for media containing solid particles (unless a V-type ball valve is selected).
❌ Avoid rapid switching to prevent water hammer effect from damaging the pipeline.
❌ Do not use in over-temperature/over-pressure conditions (refer to valve nameplate parameters).