Lanxess: Injection moulding of cast PU elastomers
Lanxess announced that Adiprene C930, a Low Free MDI based cast urethane, has proven as an appropriate material for being processed via injection moulding. The Korean company Autox developed a production process that allows cast polyurethane to be injection moulded. According to Lanxess, this innovation brings a new perspective to the cast polyurethane world as it combines the processing advantages of injection moulding along with the properties of cast urethane. Autox has recently launched a new vibrating screen for the mining industry which is made from this Adiprene cast PU prepolymer by injection moulding.
One of the benefits in working with injection moulding is the high production output rate that makes the process highly efficient and cost-effective, said Lanxess. In a limited amount of time and with a single mould, more parts can be manufactured. Cost efficiency is also influenced by labour cost which is typically lower than in pour casting. As an example, the current production time of an injection moulded mesh screen is 5 min, while the pour casting process will normally take 35 min to manufacture the screen. Adiprene LF (Low Free) prepolymer delivers improved industrial hygiene, along with ease of processing. It offers a perfect fit with the injection moulding process, as the viscosity is lower than of a conventional prepolymer, said the compay.
Vibrating screen mesh is a highly demanding application needed to withstand challenging mining operation conditions. The Adiprene C930 mining screen is said to offer outstanding abrasion resistance and rebounding properties, improving the lifetime and screening efficiency of the part. Results of this caprolactone based technology have been supported by field testing: It has been proven that the lifetime of the screen can be up to three times longer than the market high quality reference. This development allows less downtime in the mine operation leading to maintenance savings, said Lanxess.
Autox’ new development allows the processing of cast PU prepolymers, thus the moulded part presents greater performance. Complex shape parts are easier to mould as the pressure needed for the injection allows the flow to get into the part details. The injection process answers one of the main concerns of the industry: waste management, as it also allows for better quality consistency, leading to less trimmings but also less waste from reduced scrap.