JMT - 554 PILLAR TYPE COMPRESSION TESTING MACHINE These are two pillar type load frames. Two solid pillars are vertically fixed to a sturdy base and at other end is fixed a cross-head. The height of the cross head is also slightly adjustable. A lead screw passes through the center of cross-head. To the lower end of this lead screw is fixed upper platen with a spherical seat for self alignment. At the center of the base plate is fixed a jack, on the top of which the lower platen with the help of a centering pin is kept. The distance between the upper and platen is variable by means of the lead screw. A spacer block is also supplied with the load frame. This spacer block which can be fitted on the top of the jack and below the lower platen by means of centering pins helps reduce the distance between the two platens. The platens are well machined, polished and hardened. The lower platen has concentric grooves to centrally place the specimen. A dust cover for jack is supplied to prevent any grit going in the jack.