Double diaphragm pumps are the preferred pumps for glue transfer

Glue dries and hardens inside mechanical seals commonly seen in gear pumps, which makes them vulnerable to breakdowns that lead to costly production downtime. Double-diaphragm pumps do not have mechanical seals, can stall under pressure and can handle solid particles. They can be configured for abrasion resistance and the required chemical compatibility, making them very reliable in glue circulating applications for corrugated cardboard manufacturing. They are also ideal for pumping high-viscosity fluids and have lower maintenance costs.

 

To help you select and configure a QUANTM electric-operated double-diaphragm glue pump, Graco has broken down the process into three easy-to-follow steps.

The pump size to use in a glue application depends on the length of the glue circulation line and the number of glue units that need to be fed. In general, for single-wall corrugated cardboard applications, use 1” and 2” pumps. For double-wall corrugated cardboard applications, use 2” pumps. In the return line, use 1” or 2” pumps.

To pump glue in a corrugated cardboard manufacturing plant, pumps are ideally made from cast iron, polypropylene or stainless steel. All these materials fit best in terms of resistance against abrasion and corrosion. The choice depends on the chemical composition of the glue used, as well as the size of particles in the glue. Each factory produces its own glue and the composition varies from factory to factory, so these factors have to be taken into consideration when selecting the appropriate pump body material.

Santoprene is the optimal choice for internal components whichever pump body material is selected. Santoprene does not corrode, nor react if the glue is heated.

Common double-diaphragm pump configurations for glue applications in the corrugated cardboard manufacturing industry are:

• 1-inch up to 3-inch inlet size
• Cast iron with Santoprene inserts
• Polypropylene with Santoprene inserts
• Aluminium with Santoprene inserts

Graco recommends QUANTM EODDs rather than other pump technologies for glue transfer applications for the following reasons:

Does not Shear glue: Some glues are shear-sensitive, which means that the properties – and therefore the performance – of the glue could change while being pumped.

Improved Efficiency: Cut energy usage and costs by up to 80%

Handles a wide range of viscosities: QUANTM pumps are also highly tolerant to changing glue viscosity. This means that EODD pumps can continue to deliver constant and consistent flow, regardless of back pressure.

Does not heat the glue: During the glue pumping process, EODD does not heat the glue like other pumping technologies. This is important as the temperature of most glues should not exceed 43°C (110°F) otherwise they could turn into gels.

Stalls under pressure: QUANTM pumps can stall under pressure, preventing pump failures due to clogged lines or closed valves.

No mechanical seals: The absence of mechanical seals in a double diaphragm pump means less expensive wear parts and avoids failure due to run-dry pump conditions.

Simple design: The simple design and fewer parts of an EODD means easier cleaning and faster maintenance and repair. All of these translate into reduced downtime.

Minimise energy consumption: QUANTM is energy efficient, translating into lower energy consumption, thus cutting the energy bill.

Quiet operation: The QUANTM EODD is significantly quieter than a comparable pneumatic pump.

Simple control: QUANTM is much easier to control, even remotely. QUANTM includes an integrated I/O port for remote operation. This is a major advantage for metering and batching.

Reliable pump solution: QUANTM pumps are highly reliable. They are ideal for highly abrasive fluids such as certain glues. Their robust construction makes them perfect for 24/7 operation.

Safe operation: Electric pumps offer extremely safe operation; they can run dry and are in general slow-stroking during standard operation.

Graco provides a full range of QUANTM EODDs. The range is available in various configurations that provide optimal pumping solutions to meet the challenges of abrasion resistance and the different types of glue being used, as well as the variety of cleaning agents such as water, soda or others.