Adhesive Dispensing Ltd Product Catalogue

Tutorial

Timed Pressure Dispensing

Time pressure dispensing is the most common dispensing method used today for applying dots and beads of liquids and pastes. Its popularity stems from the need for process control and the fact that it is possible to dispense from disposable containers without the need for cleaning or fl uid contamina Ɵ on. Our Ɵ me ‐ pressure dispensers deliver a measured amount of air pressure, for a measured amount of Ɵ me, to a pre ‐ fi lled syringe barrel. This controlled shot of air pressure forces material out of the delivery end of the barrel, through a dispensing Ɵ p and out to the applica Ɵ on surface. A vacuum suck ‐ back prevents watery liquids from dripping and thicker materials from oozing. So a fast and consistent deposit without guesswork.

Basic Dispensing Guidelines • Small Shot Size = small dispensing Ɵ p, low fl uid pressure, short dispense Ɵ me • Large Shot Size = larger dispensing Ɵ p, higher fl uid pressure, longer dispense Ɵ me • Low Viscosity Fluid = small dispensing Ɵ p, low pressure, Ɵ me as required • High Viscosity Fluid = larger dispensing Ɵ p (tapered dispensing Ɵ p recommended), high pressure, Ɵ me as required • Posi Ɵ on syringe barrel at 45° angle • Posi Ɵ on the dispensing Ɵ p close to the work surface then ac Ɵ vate the dispense cycle and keep the syringe barrel in the same posi Ɵ on un Ɵ l the cycle is completed • If vacuum “suck ‐ back” is needed, use only enough vacuum to draw back fl uid into the dispense Ɵ p. Excessive vacuum could draw air into the fl uid and also could draw fl uid into the dispenser.

Syringe Dispensing

Factors A ff ec Ɵ ng Dispensing • Pressure: Increasing fl uid pressure will increase dot size and vice versa • Time: Increasing dispense Ɵ me will increase dot size and vice versa • Dispensing Tip Size: Larger inside diameter (ori fi ce) needle results in bigger dot size

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www.adhesivedispensing.co.uk sales@adhesivedispensing.co.uk +44 (0) 1908 686660