JAW Manhole Testing Machine is driven by Servo-hydraulic cylinder, the electro-hydraulic servo control technology, computer data colection and processing, the closed loop control and automatic detection of high-precision materials testing equipment, its by the test frame, oil source (hydraulic power source), measurement and control system, test accessories. This machine is four column frame structure, the main oil cylinder, on the main structure consists of base, oil cylinder, piston, and spokes on load sensor, light poles, beams and other components. This machine use high sealing two-way oil cylinders, high efficiency and durability is strong. This machine design has fuly considered in beautiful, convenient and safe, for example: made from the host structure with nodular cast iron precision machining, the rigidity and good stability; The height of the working table is 200mm, which is convenient for taking out the well cover test piece. Smooth bar surface chrome finish, beautiful, rust - proof Load components for high precision load sensor, the sensor one-way bearing. It is the key element of testing force. The electric signal when the force is exerted is colected and processed by computer measurement and control software. The sensor has high precision, good repeatability and long - term stability This machine equipped with high precision and deformation sensor has a height adjustment function, using sensors covers residual deformation index, height can be adjusted by hand wheel sensor arrived covers several central place, is the accurate effective measurements. The sensor is characterized by high accuracy and resolution, strong aseismic resistance and good repeatability