specialised | High and low temperature

High temperature use:

Above 60°C (140°F) you must specify temperature of use at the time of ordering. As temperatures increase, tyre materials become softer, and this lowers the load capacity. At still higher temperatures (and when hot for longer periods) the materials begin to deteriorate, which shortens working life.

Polypropylene and rubber wheels begin to lose considerable strength between 60°C (140°F) and 100°C (212°F).

Polyurethane tyres retain most of their properties up to 90°C (194°F) even for long periods (apart from a gradual lowering of load capacity) and can be used for short periods at even higher temperatures. However, caution is needed. For example, at 100°C (212°F) they lose only 5% of their tensile strength after 20 days, but at 120°C (248°F) they are down to 50% in 20 days, while at 150°C (302°F) they are down to only 15% in 5 days. Fibreglass reinforced nylon wheels are the preferred wheel for extended periods up to 210°C (410°F) (assuming most of their life is spent outside the oven), and for short periods up to 230°C (446°F). Phenolic wheels (with special inorganic fillers and PTFE bushes) are preferred for extended periods up to 280°C (536°F) (assuming most of their life is spent outside the oven), and for short periods up to 300°C (572°F). These have a thick cross secion, but are more brittle than either nylon or ordinary grades of phenolic.

For sustained high temperature use, we offer a range of cast iron wheeled castors (caution is needed as cast iron wheels will damage concrete floors), used with high temperature grease. This grease can be used up to 230°C (446°F) for long periods. Above 230°C (446°F) even more exotic greases need to be used - consult with a Fallshaw representative.