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How to Select a Glue Dispensing Valve

Selecting the wrong glue dispensing valve causes dripping, clogging, and rework. Based on 20 years of hands‑on experience, this article provides three key questions to guide selection: 1. Fluid characteristics – Thin fluids (solvents, fluxes) require a seated needle or spray valve to prevent dripping. Thick pastes (solder paste, thermal grease) need an auger (screw) valve to avoid filler crushing. Medium viscosity fluids work with time‑pressure valves but watch temperature sensitivity. 2. Dot size & speed – Sub‑millimeter, high‑speed applications demand a piezoelectric jet valve (500+ dots/sec). Larger, slower dots can use spool or diaphragm valves. 3. Maintenance commitment – Auger valves need weekly cleaning; diaphragm valves last months but don’t handle abrasives; jet valves wear nozzles every 500k–1M shots. Avoid cheap imports with no spare parts support. A quick decision table is included. Final advice: always test the valve with your actual glue and substrate before purchasing. A good valve makes dispensing boring – and boring is beautiful.