Push/Pull, Hand Geared Cranes
Light duty, single girder cranes provide maximum economy for light loads and short spans. Although designed for light duty service, quality components provide many years of dependable trouble-free service. They are available for rated loads to 2 tons and spans to 20 feet. Light duty cranes are always hand propelled.
Standard, hand propelled, single girder cranes may be arranged for hand racking by the addition of a squaring shaft drive. Hand racked cranes use 4-wheel extended wheelbase end trucks or 8-wheel end trucks. These cranes are limited to spans of 42′-0 maximum and to end trucks with 5 inch or 6-l/2 inch diameter wheels.
When electric hoists operate on the crane, they are equipped with conductors and current collectors. They can be used as transfer cranes by the addition of interlock mechanisms. The drive consists of rubber wheels mounted in each end truck which bear the bottom of the runway and provide traction to propel the crane. The wheels are connected to a squaring shaft by roller chains. The squaring shaft operates on self-aligning ball bearing pillow block; the assembly is propelled by ·a hand chain and chain wheel.
The standard location for the hand chain is 2′ -0 from the centerline of the end truck as indicated in the drawing. The hand chain may be located at any point between the end trucks when specified. A second hand chain may also be furnished when specified. The hand chain may be located up to 1 ‘-6 outside of the end truck providing the girder overhang is at least 6 inch beyond the hand chain location.