Cold Pad Batch Dosing Pump Ratio Calibration Procedures
Dosing pump ratio calibration in cold pad batch dyeing prevents reactive dye hydrolysis, shade tailing, and costly bulk fabric rejections.
Check Valve Slip
Flow Deviation
Retrograde fluid movement occurring before a non-return valve fully closes leads to incorrect dosing calculations in dye kitchen delivery networks. The occurrence of check valve slip permits a small quantity of chemical or dye to flow backward into the supply line. This reverse flow alters the volumetric accuracy of the automated dispensing system.
It can introduce serious errors in light shades where recipe accuracy is critical.
Mechanical Cause
Inertia and spring fatigue delay the seating of the internal valve disc when the pump stops. This brief delay before sealing allows the dye liquor to migrate back under the pressure differential. When check valve slip occurs repeatedly, the cumulative error in the dye mixture results in visible shade variations.
The physical wear on the sealing surface accelerates this effect over time.
Process Diagnostic
Automation software identifies the condition by tracking the post-dosing pressure drop in the delivery manifold. An immediate drop in pressure indicates that the barrier has failed to seal instantly. If the measured volume deviates from the programmed tolerance, the controller triggers a batch alarm.
Corrective Measure
Technicians replace worn springs or install soft-seated check valves to eliminate the backflow. This maintenance restores the dispensing precision to the required tolerance.