Product Category: Repair Kit for Yongda Waterjet On/Off Valve (Water Switch)

Description:
This repair kit is designed for maintaining the pneumatic on/off valve (water switch) on Yongda brand waterjet cutting systems . The kit contains the essential consumable components required to rebuild the valve, restoring its ability to start and stop the high-pressure waterjet without leakage.

The on/off valve is a pneumatically actuated component that controls the flow of water to the cutting head. Over time, the internal seals and the valve needle (stem) wear out due to high-pressure cycling, leading to water leakage or the inability to completely stop the jet .

Three Items in the Kit:
Based on standard water switch repair procedures and the components referenced in maintenance guides, the kit typically includes the following three critical items :

1. Valve Stem / Needle : The central moving part that physically opens or closes the valve seat. It is subject to wear and deformation from repeated impact.

2. Seal Assembly / Gaskets : High-pressure seals (including the main seal and backup rings) that prevent high-pressure water from leaking past the stem when the valve is closed.

3. Retaining / Seal Washers: Backup washers or retaining rings used to hold the seals in place and provide anti-extrusion support under ultra-high pressure.

Applications:

• Specifically designed for the pneumatic on/off valve (water switch) on Yongda waterjet cutting machines .

• Used to repair valves that are leaking water from the cutting head when the machine is in "stop" mode.

• Suitable for restoring a valve that fails to fully open or close, affecting cutting performance.

Features:

• Restores Valve Function: Replaces worn internal parts to stop water leakage and ensure a tight shut-off .

• Includes Critical Consumables: Contains the valve needle, high-pressure seals, and backing washers required for a complete overhaul.

• Easy Maintenance: Designed to allow rebuilding of the valve without replacing the entire expensive valve body.

Maintenance (Installation Procedure):

• Preparation: Fully depressurize the waterjet system. Disconnect the air supply to the valve .

• Disassembly: Open the air valve to retract the stem. Remove the top fittings and carefully extract the old needle and seals .

• Cleaning: Clean the valve body cavity thoroughly to remove debris and old seal residue.

• Lubrication: Apply a small amount of hydraulic oil to the new seals and needle during installation to prevent dry start-up .

• Adjustment (Critical): After reassembly, tighten the pneumatic cylinder hand-tight until it stops. Rotate it back 360 degrees (one full turn), then advance it 180 degrees (half a turn). Cycle the air valve to test for proper movement (not too tight or loose) .

• Testing: After installation, pressurize the system and check for water leaks for 10 seconds before resuming normal cutting .