It introduced a multifunction relay electrical characteristic tester with fast speed, high accuracy, high reliability. It can satisfy the requirements of large automatic production.

The technical principle of the intelligent high speed tester for solidity of moulding sand is described briefly. The design, calibration and application results of the tester are introduced.

This paper presents an analysis and study on the vibration and unstable factors which affects the stiffness of the speed Tester for high speed heavy load large grinding wheels;