What is a purging compound?
Purging compound is a product that is used by most thermoplastic producers for cleaning screws, mold, nozzles, die or hot runners of injection moulding machines and extruders. A purging compound for plastic has been developed as an alternative to virgin resin purging for reducing machine downtimes and scrap rates when material or colour change occurs.
Why a purging compound should be used?
The prime and simple reason is that using a purging compound for plastic is to get a faster and more effective solution. The purging material for injection moulding contains components such as emulsifiers, and abrasive or foam agents which help in speeding up removing contamination out of the barrel. The purging compounds are specifically designed for this purpose. It is faster and more efficient than using resins that were designed to be moulded into parts not to eliminate impurities from the system.
Besides that using purging compounds for plastic also helps in:
Purging compounds help in clearing out the residues of last production and colours effectively which further reduces the amount of waste generated. Furthermore, it enhances the productivity and efficiency of your factory.
Time is extremely precious in a production facility. Purging compounds help in reducing the time wasted in resin changeovers.
Elimination of Contaminants
The chemical components of purging compounds for plastic help in eliminating carbon residues, colour streaks and gels during production changeovers. It improves your factory rejection rates and avoids frustrating machine stops during production.
Preventing Screw Pulls
Contamination when not removed can hamper the functioning of your machine and you may need to pull out the screw to do a manual cleaning at some point in time.
Removing contamination from the Hot runners
Many injection moulding changeovers might take you longer when there are stubborn colour residues inside the hot runners. Now there are purging compounds in the market that can be used safely through the mould. For this scenario, unfilled purging compounds are especially useful.
Reduction in Rejection Rates
Properly cleaning the machine after a material or colour change or long shutdown helps you in preventing product rejections by your quality team or uncomfortable orders returned by your customer.
Purging compounds helps in decreasing cost by reducing downtime and scrap during colour and material changes. During the evaluation of this solution all the factors such as the material, machine, labour, scrap, lost production, customer satisfaction and purging compound price need to be considered.
What are the different types of purging compounds?
The different types of purging compounds include:
Mechanical Purging Compound
A mechanical purging compound is a common type of purging compound that depends upon the complete force required to push contamination out of the barrel. The mechanical purges typically come in pellets where common resins with a low Melt Flow Index are combined with some additives. Such compounds are available in different grades.
Liquid Purging Compound
Liquid purging compounds are different from conventional purges in terms of behaviour. These purges rely on chemical reactions that will increase the flow and generate instability inside the barrel. It further speeds up the contamination removal process and reaches negative flow sites where the residues stay for a longer period. Liquid purging compounds are usually used at small percentages due to their concentrated formula.
Chemical Purging Compound
Chemical purging compounds also make use of chemical agents for cleaning. Usually, these compounds need soaking for 5 to 30 minutes. Chemical purging compounds also come in different grades. These compounds are the most expensive formulas.
We at UNICLEANPLUS™ are a highly reliable and leading purging compound supplier known for providing highly effective purging solutions for various applications. Our extremely efficient purging compounds are developed for covering a wide range of operating temperatures, equipment types, and process applications. At UNICLEANPLUS™, we provide the highest quality purging material for injection moulding that addresses the challenges of the thermoplastic processors ultimately enhancing their performance and operations. If you want to try our purging compounds free sample, then get in touch with us today!