Multi-functional core drilling rigs for concrete of model HZ-20 Gasoline engine is employed for power, with features of convenient start, reliable running and easy operation. Incision and grinding for core shall be carried out with the help of wheelhead and saw blade. It is applicable for core drilling test for concrete and asphalt road surface at roads, airport, dock, dam and etc. Technical parameters: 1.Maximum diameter of core drilling: 200mm 2.Maximum depth of core drilling: 700mm 3.Diameter of incision and grinding: 150mm 4.Power of motor: 5.5HP