Valve Seat Boring Machine Model: BV90 with high availability meets the requirements of boring, reaming and cutting machining for high accuracy valve guides and valve seats. Triple air-float patented centering system and powerful spindle with built-in motor. Designed for the valve seats from the smallest to the bigger diameter. This machine can repair any existing engine, from the micro-engine up to the big stationary engine, machining capacity from 18mm to 90mm.To reach the requirements of high precision machining for valve guides with a small diameter of 4mm.