Guidelines for Installation and Maintenance of Sanitary Pneumatic Flange Stop Valves:

1、 Installation specifications

1. Preparation before installation

Clean environment control: The installation area should meet the dust-free standard (ISO 14644 Class 8), wear sulfur free gloves during operation, and avoid contaminating the valve body mirror surface (roughness ≤ 0.8 μ m).

Component inspection: Confirm that the valve body is free of scratches and the sealing surface is intact, and verify the flange size (DIN/ISO standard) and pneumatic actuator model.

• Pipeline pretreatment: Rinse the pipeline with food grade cleaning agent to remove welding slag impurities, and polish the welding interface to Ra ≤ 0.4 μ m.

2. Installation operation process

Flange docking: Use sanitary grade gaskets and gradually tighten the bolts in diagonal order (torque ≤ 50N · m) to ensure even force distribution.

Flow direction calibration: The arrow direction of the valve body should be consistent with the flow direction of the medium, and the valve stem should be installed vertically upward to avoid lateral force.

Gas source connection: The pneumatic pipeline needs to be equipped with a filter pressure reducing valve, and the gas source pressure should be stable at 0.4-0.7MPa. The response time of the test actuator should be ≤ 3 seconds.

3. Verification after installation

Sealing test: Introduce clean water or inert gas at 1.5 times the working pressure and maintain the pressure for 5 minutes without leakage (in accordance with ANSI Class VI standards).

• Action test: Open and close the valve 10 times throughout the process, check that the valve disc movement is unobstructed, and the position feedback signal is accurate.

2、 Maintenance points

1. Daily maintenance

Cleaning process: Rinse the valve chamber with sterile water every week, and immediately neutralize any residue with alkaline cleaning agent after working with strong acid medium.

Lubrication management: Add food grade lubricating grease (such as PTFE based) to the valve stem threads every quarter, and prohibit the use of sulfur-containing grease.

2. Regular maintenance

Sealing system inspection: Check the wear of the valve seat sealing surface every 6 months (if the depth is greater than 0.05mm, it needs to be replaced), and replace the O-ring immediately if it ages and cracks.

• Maintenance of pneumatic components: Remove carbon deposits from the cylinder and check for elastic deformation of the diaphragm (if the deformation exceeds 15%, it should be replaced).

3. Shutdown maintenance

Long term shutdown: Drain the medium inside the valve, inject rust inhibitor, and install a dust cover on the pneumatic actuator.

Sterilization cycle: When using SIP online sterilization, control the heating rate to be ≤ 2 ℃/min to avoid thermal shock failure of seals.