Injection moulding is the dominant process for producing plastic parts at scale in the UK and Ireland, used across nearly every manufacturing sector. The reason it shows up everywhere is straightforward: it produces precise, repeatable parts in a wide range of materials, scales economically from thousands to millions of units, and integrates well with downstream operations like printing, assembly and decoration. For most plastic parts produced in quantity, injection moulding is the default answer.

Injection moulding costs break down into six components that every quote has to cover: the tooling, the raw material, the machine time (set by cycle time and hourly rate), the order volume, and any post-mould operations like assembly or decoration. The actual cost of any specific part depends heavily on which of these is dominant, and that varies enormously from one part to the next. Understanding the process is how you compare quotes that look wildly different on paper.

Injection moulding, blow moulding and rotational moulding produce very different kinds of plastic parts, and the right process depends on a number of factors, including part geometry, required properties, annual volumes and economics.