Peristaltic Pumps with Onboard Variable Speed Drive for Water Based Glue and Ink Transfer
Adhesive Types, Background & Application
Careful consideration must be taken with pump selection when handling the transfer of glues. Depending on the type, they can be highly viscous as well as harden and solidify when exposed to air. Glues are typically either water based or solvent based, in this instance the former is relevant.
PVA is a common example of water-based glue, natural or synthetic soluble polymers are added to water to form the liquid, this type of product only works if the applied surface is permeable, for example wood and paper. The glue sets once the water has evaporated from the surface, the bond can then be broken easily by the reapplication of water, these glues are popular as they are low cost and friendly to the environment.
An existing customer - a World-renowned paper tissue manufacturer was having difficulty with their existing pumps used for the transfer of a glue/ink mixture used for various processes in their manufacturing plant. They previously purchased a peristaltic pump from us for an ink application and were so impressed with the quality, efficiency and ease of maintaining that they wanted to replace other pumps currently installed with the same technology.
They have a large holding tank containing the mixture, with smaller day tanks located throughout the plant next to different machinery dependant on the process. The purpose of the unit is to fill the smaller tanks on demand and to ensure they never fall below a minimum level that could cause a stop in production. We were informed that 1 hour of downtime is equal to around £3000 of lost revenue, therefore it is crucial that the solution selected was reliable and quick to maintain if a fault occurs.
The average flow rate required to meet demand is 500L/hr, however the production manager wanted the ability to increase flow up to 900L/hr if demand increased, an ability they did not previously have. The glue mix is viscous therefore the pumps needed to be capable of handling the high viscosity while self-priming from the feed tank. The capability to clean the pumps easily was also a must as it is crucial to avoid the product setting within the unit after production has completed.
Our Non-Clogging, Low Maintenance Solution
Peristaltic glue pumps cover all the customers’ requirements, their ability to self-prime, transfer high viscosity fluids and the seal-less design make them an excellent choice. The only component that encounters the fluid is the internal rubber hose, this is easily cleaned by flushing through warm water after demand has finished.
The absence of a mechanical seal, balls and valves found in other pump designs ensures the pump does not become clogged, the ability to reverse the flow is also an excellent feature if somehow this does occur. As hose pumps can dry run indefinitely, it allows all the product to be emptied completely from the hose without worry of causing damage like in mechanically sealed designs.
We supplied 2 peristaltic hose pumps complete with built-in variable speed drive, this allows the customer to easily alter the flow rate by simply rotating a potentiometer dial located on the motor. Having the inverter directly mounted on to the motor negates the need to install an external local inverter, something that this customer wanted to avoid.
In addition to the inverter, we installed various other features to make life as simple and safe as possible for the operators. We included an emergency stop button on the motor so that the glue pump can be stopped without having to reach a control panel, also included is a reverse switch to allow flow to be reversed if required, for example if too much product has been transferred or a blockage occurs. The final feature is a hose leakage detector, this sensor detects if the internal hose has ruptured, it sends a signal to the control panel to warn the operator. This allows the fault to be detected early and for maintenance to be performed quickly before there is a loss in production, downtime is then minimised and ultimately costs are saved.
To further assist the customer and to ensure any possible downtime is reduced, we supplied a spare hose and lubricant. As the hose is the only wearing part, the number of spare parts required on site is very low, simply replacing the hose and applying the grease is all that is required to get the pumps operational again after a rupture.
Below is the specification of the glue/ink pumps that were installed:
Water Based Glue - Ink Mix
Natural rubber hose
266 - 989 l/h (4.43 - 16.48 l/min)
1 Bar (Maximum working pressure of 8 bar)
BSP 1" - Stainless Steel
0.75 kW, Integrated Frequency Inverter, 20 - 75 Hz / Speed: 18 - 67 RPM