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Acetal is a semi crystalline engineering plastic and it is a polymer manufactured by polymerisation of formaldehyde.


It is probably one of the best engineering plastics around for machining as it is very easy to machine, leaves a very smooth and high quality surface and will suit modern high speed efficient CNC machines. Acetal is an exceptional engineering plastic for dimensional stability which means that high precision and close tolerance component can be produced and because Acetal absorbs almost no moisture and offers good creep resistance it will continue to remain accurate over a long duration and over a vast range of environments. Acetal has a high mechanical strength, hardness and stiffness which help Acetal become an engineering plastic that is often replaced and substituted for steel or other metallic materials. Acetal is one of the best engineering plastics for is sliding abilities and has a lower coefficient of friction than Nylon.

Temperature values

Acetal has an optimum long term service temperature range of approximately plus 100°C and a maximum short term temperature range of approximately plus 130°C. Acetal can melt at a temperature of plus 165°C and Acetal also has a minimum operating temperature of between -30°C and -50°C.


Oilon is green cast Nylon 6, which has been blended with a non leech or drying out liquid lubricant. This increases sliding benefits and bearing life up to 5x making Oilon exceptional where bearing lubrication is an issue.


HDPE is an engineering plastic that is often underestimated and although HDPE is popular, it is sometimes confused with other engineering plastics. HDPE is a shortened name for High Density Polyethylene and available in two main grades, 300 and 500 grade. The higher the HDPE grade number the higher the density of the plastic is which improves the performance of the product. Although HDPE is unable to be bonded with currect adhesives, HDPE can be welded with purpose designed and economical welding equipment.


HDPE has very low friction properties which are some of the best within the engineering plastics range and HDPE helps produce low friction components. HDPE also has excellent abrasion resistance which helps provide components that are suitable for high abrasion applications. HDPE will absorb very low amounts of moisture which help creates components that are stable over a long period of time.


Arguably one of the most important engineering plastics is a material called PTFE. Although PTFE was invented back in the 1940's, it still remains a critical component that continues to outperform almost all other engineering plastic in specific and critical areas.


PTFE is specially important because of its outstanding lack of friction and slippiness, this is so incredibly low that is has been described as being the most slippy solid material known to man and PTFE can be cut into strips and can offer a massive improvement in the sliding components. PTFE is also highly specified due to its very high temperature resistance allowing components to withstand almost double that of other types of engineering plastic. PTFE has the capability to also withstand very strong acids and chemicals helping to provide solutions to acid storage and chemical problems. High electrical resistance is yet another feature of PTFE and PTFE is often used in high end electrical resistance appliances.

Temperature values

Maximum long term working temperature is plus 260°C. Maximum short term working temperature is plus 260°C. Co-efficient of friction is 0.08. Co-efficient of expansion is 12. Melting point is plus 327°C.


Tufnol is a very rigid product and has grades suitable for either mechanical, electrical and general purpose applications.

  • Whale Tufnol is excellent for bearings, bushes, slide ways and wear strips.
  • Kite Tufnol is excellent for circuit boards, covers and high electrical insulation.
  • 1P/13 Tufnol is great for jigs, fixtures and lower voltage electrical insulation.

Tufnol can also be known as Bakelite, SRBP, SRBF, Paxolin or Phenolic sheet.


Whale is the grade specifically for engineering purposes. Whale Tufnol Sheet is perfect for wear resistant components such as bearings, bushes, gears, washers, slide ways and above waterline marine use. Whale is dimensionally very stable, and can be either run dry or lubricated with water, oils or grease.


Kite is an excellent composite plastic that has a distinctive dark brown colour. Tufnol Kite grade is the high voltage electrical insulator for circuit boards, terminal boards, washers, spacers, covers and protectors. Tufnol Kite is a very rigid material that has low moisture absorbtion and is easily machined.


1P/13 Tufnol Sheet Is the standard low cost grade suitable for jigs, fixtures, base plates, spacers and low voltage insulation. Tufnol 1P/13 is similar but has a higher mechanical and impact strength than Kite grade and is easily machined. Due to its good all round properties Tufnol IP/13 has become very popular for less demanding mechanical and insulation duties.


Ultra High Molecular Weight Polyethylene is a super engineering plastic that is probably not as well known as some other engineering plastics but can out perform its relatives in a number of important areas.


UHMWPE has a few very important properties and the first would be its incredible resistance to abrasion. UHMWPE can out perform almost any engineering plastic for abrasion resistance. Another important property of UHMWPE Sheet is it's incredibly low co-efficient of friction, this is one of the lowest of all engineering plastics and will produce components with a very high life span with very low drag. UHMWPE is resistant to many dilute acids, solvents and cleaning agents.

Technical Data

UHMWPE has a maximum operating temperature of plus 90°C and a short term operating temperature of plus 120°C. UHMWPE has a tensile strength of 17MPa and a crystal melting point of plus 135°C. UHMWPE has a water absorption figure of 0.02 at saturation and a co-efficient of friction of 0.29.

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Page last modified on July 16, 2017, at 09:09 AM