Glue Types: How to Pump Glue

Pumping glue can pose challenges due to its tendency to harden and solidify upon exposure to air. 

Water Based 

Water-based glues, like PVA glue, comprise natural or soluble synthetic polymers in powdered form, which are then mixed with water to create a liquid adhesive. Once applied to a permeable surface such as wood, the water evaporates, leaving a strong bond. This bond can be dissolved again by applying water. These types of glue are not only cost-effective but also environmentally friendly. 

Solvent Based

Solvent based glues are a mixture of polymer based ingredients mixed with solvent. Once the glue is applied and the solvent is exposed to air, the solvent begins to evaporate until cured when the bond is at its strongest. The bond is more of an industrial bond and once applied is difficult to break unless a chemical such as acetone is used. Solvent based glues are very unforgiving and also more harmful to the environment and so care must be taken during disposal. 

Viscosity: 10cst- 1400cst
Sg: 1 - 1.3

At North Ridge we understand how adhesive can affect pump internals and can specify pumps with the following features to ensure a smooth pumping process: 

Cleanability – Pumps can be specified for ease of strip down and cleanability 

Seal less – Pumps can be specified without internal valves or balls which can become clogged ensuring there is little down time, which are reversible to ensure product can be emptied from hoses with dry run capability to completely empty the pump 
 
Seal Flush – if a mechanical sealed pump is required a seal flush can be used to ensure the faces do not stick and cause seal failure. 

View our range of pumps for Glue

What to consider when selecting a pump for glue 

When pumping glue, several critical considerations come into play to ensure efficient operation, maintain product integrity, and prolong equipment lifespan. Here are key factors to keep in mind: 

• Hardening Properties: Determine whether the glue hardens when exposed to air. Certain adhesives, such as cyanoacrylate (commonly known as super glue), polymerise rapidly upon contact with air. For such adhesives, it's crucial to minimize air exposure and ensure airtight storage and pumping systems to prevent premature hardening.

• Cleaning Procedures: Consider the cleaning process for the pump and associated equipment. Glues often have adhesive properties that can adhere to surfaces, leading to build up and clogging if not properly cleaned. Select pumps that are easy to disassemble and clean thoroughly to prevent cross-contamination and maintain operational efficiency.

• Temperature Sensitivity: Assess the sensitivity of the glue to temperature fluctuations. Some adhesives exhibit changes in viscosity with temperature variations, becoming more viscous when cooled. This can affect pump performance, requiring adjustments to flow rates or heating systems to maintain consistent viscosity and flow characteristics.

• Material Compatibility: Ensure that the materials used in the pump construction are compatible with the glue being pumped. Certain adhesives may react with or degrade specific materials, leading to contamination or equipment damage. Choose pumps made from materials such as stainless steel, PTFE (polytetrafluoroethylene), or other chemically resistant materials such as EPDM suitable for handling the glue without adverse effects.

• Flow Control and Precision: Consider the requirements for precise flow control and dispensing accuracy. Some applications demand precise dosing and uniform application of adhesive, necessitating pumps with adjustable flow rates, fine-tuned control mechanisms, and consistent dispensing capabilities to ensure optimal bonding performance.  

Some pumps can be designed to pump from 2 containers at the same time.  For example where the  adhesive is a two part epoxy, and pumped to a common manifold where the mixtures react.

• Maintenance and Downtime: Evaluate the maintenance requirements and potential downtime associated with the pump. Regular maintenance, including cleaning, lubrication, and component replacement, is essential to prevent malfunctions and extend equipment lifespan. Choose pumps with robust design features, easy access to critical components, and reliable performance to minimise downtime and optimize productivity. 

By addressing these considerations, you can select the appropriate pumping equipment and implement effective procedures for pumping glue, ensuring consistent performance, product quality, and operational efficiency in adhesive application processes. 

Contact our processing specialists to discuss your requirements.