An efficient compounding operation requires resins, fillers and additives, as well as finished compounded materials, to be in the right location in the plant at the right time. Pneumatic conveying and handling of materials on the shop floor is an essential tool in achieving this. However, materials such as calcium carbonate, barium sulphate, magnesium hydroxide and alumina trihydrate - all commonly used in the compounding industry to provide opacity, improve surface finish, increase impact strength and stiffness, and improve flame retardant properties – can provide particular handling problems.
Materials handling specialist Penta, part of the Piovan Group, also sees flexibility becoming more important. A company spokesperson says that over the past 10-15 years many plastics compounders have built up processing plants that are capable of high throughputs, but a consequence of that has been reduced flexibility in recipe and colour variations. As a result, these plants are not economic if small production lots are required. However, the current market now needs a high degree of flexibility on colours and different types of product. Penta reports an increasing number of requests to upgrade existing plants on a ‘smart’ basis – providing easy technical solutions at low cost. However, Penta says that re-designing and re-sizing materials handling systems and equipment is not always a straightforward operation. The company explains that a further issue it currently faces is that a lot of compounding bulk materials handling systems are at least 30 years old. While the metal is still sound, hardware such as rotating parts, filters and control systems are frequently outdated and this can make the whole material logistics uneconomic. In theory, this means a lot of current systems ideally require a complete re-build, but Penta acknowledges this is unrealistic. It is rarely possible to shut an operation down completely and transfer to a new site, so solutions are needed to install modern systems with the shortest downtime possible.
The main technology issue for any manufacturer of bulk materials handling equipment is flexibility. “For example, this means designing in a way that reduces cleaning downtime to zero or as little as possible,” says a Penta spokesperson. “Any materials handling operation, including dosing and weighing systems, also requires precision to minimise the cost of raw materials. This is particularly necessary when trying to reduce costs through the use of fillers, such as calcium carbonate, in products.”
Read the complete article published on Compounding World.