Although many facilities rely on standard molded components, custom machined polyurethane parts are another option for facilities that need a unique component design. Both molds and polyurethane itself can be machined into custom shapes, but when shaping polyurethane, it takes a specialist in the field. Polyurethane is adversely affected by the stresses of machining, so shaping equipment has to be configured precisely to the type of polyurethane and its physical properties. But with the proper settings, polyurethane can be shaped just like metal, and shaped using equipment that can’t be used with metal. This makes it an ideal alternative to polyurethane production runs that only require a small number of parts.
How Custom Machined Polyurethane Parts are Made
Several techniques are used in the production of custom polyurethane components, giving engineering teams incredible range in design and creation. Specifically, this is how polyurethane can be machined:
- Contouring – During the contouring process, the polyurethane’s surface is shaped. Contouring is almost always a part of the custom part production process, but even still, care must be taken in regards to the speed of cuts and the cutting tool that is used. The survivability difference between hard and soft polyurethane is significant, and if the tool spins too fast, it can damage soft polyurethane. For this reason, machining teams usually start with slower speeds, ramping the tool up once the material proves its integrity.
- Tooling – Tooling machines can be configured for use with a lathe or with a turret, and during the tooling process, the polyurethane is spun at high speeds while a cutting tool moves across the material on a locked axis. The cutting tool alters the diameter of the material, though again, the hardness of the polyurethane will dictate the proper technique. If the material is hard enough, the machining process will emit a great deal of heat, which must be controlled with the application of coolant. Softer materials, though, can often be machined dry. Newer tooling technology offers Y-axis tool movement as well, which speeds up production by allowing the tool to move more efficiently over the material’s face.
- Sawing – Although a secondary machining method behind milling and tooling, sawing is still in use in many machining shops. Band saws are a standard piece of technology in this process, as band saws can be fitted with cutting edges of different lengths and teeth spacings. This ability to switch out cutting edges is essential when switching between soft and hard polyurethane, and ensures the material can be customized adequately.
The Benefits of Custom Machined Parts
Using these techniques, along with industry best milling and machining equipment, MUI can produce a range of custom polyurethane components for any industry. This includes bushings, liners, gears, rollers, tubes, pads, rings, nozzles, seals and any intricate component that a client might require.
But why should a client choose polyurethane over metal, rubber or plastic? While these materials can serve well in some settings, polyurethane has been designed to handle some of the toughest environments on the planet, and even beyond. And polyurethane can perform its role efficiently and safely. This is what polyurethane offers to a project:
- Versus Metal – Polyurethane can be fabricated with hardness that rivals some metals, but it is much lighter, reducing installation and operational costs. Polyurethane also offers superior resistance to abrasion, and some varieties offer superior corrosion resistance as well. Polyurethane is non-conductive and will not spark, which makes for safer operation, and they produce less noise during operation as well. Polyurethane is also less expensive and less time consuming to fabricate, shortening lead times considerably.
- Versus Rubber – Rubber has been replaced by polyurethane in a number of applications, most notably in the oil and gas field. Whereas rubber once was used in pigs and pipe linings, it was replaced in favor of polyurethane, as the latter is much more resistant to corrosion and hydrocarbons. Polyurethane withstands cutting and tearing forces better, as well as abrasion, and it can bear greater amounts of weight while maintaining its shape. And with greater compatibility with tooling and molding, polyurethane is a more versatile option overall.
- Versus Plastic – Polyurethane offers better overall durability compared to plastic, particularly in abrasion, low temperatures and radiation. Polyurethane is more resilient than plastic, so it will hold its shape better, as it is fabricated with better elastic memory. It also costs less to tool polyurethane.
Polyurethane is an impressive material, which is why more and more industries are relying on custom components for their projects. And with so many options in fabricating polyurethane components, there is a cost-effective approach for every client.