When heavy plate shears are sometimes used, the blade gap may be adjusted. Whether the blade gap can be adjusted properly is the main factor to reflect the quality of heavy plate shears and extend the blade life.

The ball valve of heavy plate shearing machine is used to measure the uniformity of the gap between the high and low blades. The detailed method is to open the oil circuit by quickly turning the ball valve when the high and low carriage moves to the lower dead point by a single journey, so that the upper carriage stops at the lower dead point. When the clearance is adjusted, hold the locking screw temporarily, then turn the handle to the required scale value, and then lock the screw. Then connect the micro opening and closing ball valve, so that the upper tool rest is descending section by section on the whole path, and then measure the evenness of the blade gap section by section.