In line with the relevant provisions of the general portal crane GB/T14406-1993 and GB5905-86.
In general, the lifting capacity is below 50t, the span is within 35m, no special use requirements, it is appropriate to choose single main girder type. If the door leg width is required, the working speed is high, or often lifting heavy, long and large pieces, it is appropriate to choose double girder portal crane.
Second, the span and cantilever length
The span of the portal crane is an important factor affecting the quality of the crane itself. In the selection, the span should be reduced as much as possible under the premise of meeting the conditions of use of the equipment and meeting the standards of the span series.
Three, the wheelbase determination principles
(a) Can meet the stability requirements of the gantry along the direction of the crane track.
(b) The profile of the goods should be able to pass smoothly through the outrigger plane steel frame.
(c) pay attention to make the wheelbase B and span S into a certain proportional relationship, generally take the wheelbase B = (1/4-1/6) S.
Four, portal crane spacing size determination [2]
In the work, the gantry crane external size and the goods of the yard and transport vehicles channel should be left between a certain space size to facilitate loading and unloading operations. General transport vehicles should be kept at a distance of 0.7m or more from the door leg when loading and unloading within the span. The spreader should have a spacing of 0.5m or more from the transport vehicle when not working and a spacing of 0.5m or more when the goods are over the door leg.
