A common request we receive at CRG is to produce machined plastic parts from UHMW and HDPE for our customers. While these two materials are widely used to produce plastic parts, there are some differences between them that customers should be aware of.
UHMW (Ultra High Molecular Weight) polyethylene plastic has one of the highest impact strengths of any thermoplastic and has excellent abrasion resistance and tensile strength. UHMW has the highest impact strength of all the polyethylenes and the material will outwear carbon steel 10 to 1 in some applications. UHMW also has excellent resistance to stress and cracking, and the material has a low coefficient of friction (UHMW is self-lubricating). This last property makes UHMW a preferred material for parts in sliding applications, those involving rough surfaces, or any situation where overcoming friction is important.
HDPE (High Density Polyethylene) has a somewhat lower tensile strength than UHMW. It possesses excellent chemical resistance and low moisture absorption. HDPE is used in a variety of applications and industries where impact resistance, high tensile strength, low moisture absorption and chemical and corrosion resistance properties are required. In terms of machining, HDPE finishes a little better than UHMW, although both materials machine well.
A wide range of UHMW and HDPE grades are now available to produce parts which support specific applications. For example, AS/UHMW is available as an anti-static grade for producing parts which protect against the build-up of electrical charges.
Both UHMW and HDPE materials are available in grades which meet FDA guidelines. This makes these grades a good choice for producing parts that will be used in sanitary or hygenic applications, including those in the pharmaceutical and food industries. you are unsure about the range of UHMW and HDPE materials available, or which grade will work best for your particular application, CRG will be pleased to assist with material guidance and selection.
Which material you should choose very much depends upon your application. Parts made from either UHMW and HDPE will perform well in many applications. However, since HDPE is a more rigid material than UHMW, it has a slightly lower resistance to impacts. HDPE may be preferred in certain applications where aesthetics and part appearance are important, as it tends to have a smoother finish than UHMW. However, UHMW will be the preferred material where greater resistance to impacts is desired. Due to UHMW’s high molecular weight, UHMW parts will also perform better where overcoming the forces of abrasion and friction is desired. Due to its low coefficient of friction, parts made from UHMW will also produce less noise when in motion.
Examples of parts which CRG can produce using UHMW and HDPE materials include the following:
All machined plastic parts from UHMW and HDPE which CRG makes are produced under controlled conditions in our ISO 9001-certified facility. All jobs are inspected throughout our manufacturing process and a final inspection is performed on each order before it is shipped. Our reputation for industry-leading responsiveness is unsurpassed and we specialize in the fast order turnaround of both small- and large-run orders.
Because there are a wide variety of plastic materials and grades available in the marketplace, CRG can provide guidance on material selection for your application. If you require machined plastic parts from UHMW and HDPE, or other plastic materials, please contact our sales department for assistance at email@example.com.
Abrasion And High Wear Applications