Installation of a leveller by adaptation with a sand cushion

Abstract

The installation of a leveller in the heat-treatment room of the strip-rolling shop No. 6 of the II'ich metallurgical plant in ZManov was made difficult by the lack of the necessary elevator equipment. OnIy one bridge crane is available here with a a-ton load-lifting capacity, while the upper and the lower mounting platesfor the lever alone weigh more than 40 tons each. A technique for installing a leveller of overall dimensions 9x360x 2800 (165 tons) was developed and applied at the SU No. 3 of the "Donbassdomnaremont" Combine in Zhdanov. The leveller components were roughly assembled with the aid of an EDK-500 railroad crane, wkh an 80-ton load lifting capacity, on a bed of crossties laid on the railroad track 40 m in front of the entrance. The two halves of a six-axle steel transporting lorry with a 230-ton load carrying capacity were roiled up to the lower mounting plate and electrowelded to it. The leveller thus assembled (item 4 in Fig. 1) was driven to its intended site by this steel lorry (5) with the aid of two flat cars 2, 3 (convoy) and a steam engine 1.It was technically more diffieuk to devise a mechanism or an apparatus for lowering the assembled leveller into the pit 2080 mm deep. The engineers decided, therefore, to use for this purpose sand cushions, i.e., sand jacks.A sand jack was made of tubing, 325 mm in diameter and 28 mm in wall thickness. One jack weighed 970 kg, and the 0.2 m 3 of sand in it weighed 138 kg. The sand for this had to be dry and coarse-grained, 1.5 x 1.5 mm sieve size.The leveller as assembled was installed into the final position by smooth lowering (Fig. 2) with the aid of four sand jacks, each having a 50-ton load capacity, as follows. After the leveller had been brought in close, support stubs 8 were first installed with very accurately horizontal top surfaces. On these stubs were placed the sand jacks 5. Cantilever brackets 2 together with cylinder piston rods 4 (tube 245 mm in diameter) were then welded to the mounting plate 1 of the leveller. Meanwhile, index SU-3 of the "Donbassdomnaremont" Combine, Zhdanov.