... PCD drilling bit Concrete core drilling equipment(EN 1254-1)Concrete Hollow Boring Machine, drilling machine, testing equipment1. Application:STHZ-20 concrete ... drilling of concrete, limestone and foundation for compression and flexural testing in highway, airport, port and dam etcIt also can be ... engine (power: 5.5HP, speed: 3600r/min) Concrete core drilling equipment(EN 1254-1)