The larger the diameter greater the load that can be carried. Rough surfaces or high impact loads halve the capacity. Roller bearings permit higher wheel loads for hand pushing due lower friction.

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Tractive power can come from either fixed track chain towing, or free movement tractors. Tractors used indoors, in warehouses, factories etc., are restricted by necessity to about 10 kmph. But even at this slow speed, both the wheel and the castor can suffer severe impacts from uneven surfaces. The castors and wheel chosen must be strong enough to cope with this.Outdoor use can be even more sever

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Castors used indoors, in warehouses, factories etc., are restricted by necessity to about 10 kmph. But even at this slow speed, both the wheel and the castor can suffer severe impacts from uneven surfaces. The castors and wheel chosen must be strong enough to cope with this.Outdoor use can be even more severe.

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Castors used indoors, in warehouses, factories etc., are restricted by necessity to about 10 kmph. But even at this slow speed, both the wheel and the castor can suffer severe impacts from uneven surfaces. The castors and wheel chosen must be strong enough to cope with this.Outdoor use can be even more severe.

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