1. The application and characteristics of steel pipe hydrostatic testing machine

  The steel pipe hydraulic testing machine is a special equipment for pressure testing of steel pipes. The equipment is mainly used for pressure testing of stainless steel pipes, alloy steel pipes and straight seam welded pipes of various pipe diameters.

  The hydraulic press uses two lifting rollers to support the steel pipe to be tested, and the main oil cylinder is used to press the steel pipe between the fixed push plate and the movable pressing plate to seal the pipe ends of the steel pipe. The high-flow low-pressure pump is used to complete the water inlet, and then the high-pressure pump is used to complete the pressure test.

  2. Structure and working principle of steel pipe hydraulic testing machine

  The equipment consists of hydraulic cylinder support, a fixed plate, a movable push plate, girders, feeding roller, loading structure, unloading structure, hydraulic system, water system and electric control system.

  (1) Hydraulic cylinder support

  The hydraulic cylinder support is used to support the cylinder, which is responsible for pushing the movable push plate during work.

  (2) fixed plate

  The fixing plate is welded with high-quality carbon steel plate, which is located at the end of the machine and welded to the girders. The center of the plate is provided with an inlet pipe through which the water pump injects water into the pipe to be tested.

  (3) Movable push board

  The movable push plate is placed at the other end of the device, and is pushed by the main oil cylinder to press the pipe end to achieve sealing to be tested. Water pipe is installed on the movable push plate to observe whether the steel pipe is filled with water. When the movable push plate end evenly overflows the water, it indicates that the water in the steel pipe is full, the low pressure pump should be stopped, and the high pressure pump should be used to pressurize the water.

  (4) Girders

  There are 4 girders, which are responsible for connecting the hydraulic cylinder support and the fixing plate. At the same time, it also plays a guiding and orbital role for the activity of the push plate. The girders are subjected to large tensile stresses during operation and require sufficient strength.

 (5) Feeding roller

  There are two feeding rollers, which are placed between the movable push plate and the fixed plate and are responsible for supporting the steel pipe under test. The rollers are pushed up and down by the hydraulic cylinder to adjust the position of the different steel pipes in the hydraulic press.

  (6) Hydraulic system

  The hydraulic valve parts used in the hydraulic system of the equipment are supplied by the best quality manufacturers in China, ensuring safe and reliable operation. The hydraulic system includes hydraulic stations, valve blocks, hydraulic pipes and accessories.

  (7) Hydraulic system

  The hydraulic system consists of a low pressure system and a high pressure system. The low-pressure system consists of two large-flow multi-stage submersible pumps and corresponding pipelines. The tested steel pipes are filled with water in the shortest time. The high pressure system consists of plunger high pressure water pump and corresponding pipes, and the maximum water pressure can reach 25 MPa. The water system consists of  water pump station, liquid filling system, control valves, pipes and accessories.

  (8) Electronic control system

  The electronic control system uses programmable controller (PLC) to control the equipment with precise control and automation. The electrical measurement and control system includes total power cabinet, control cabinet (PLC), and on-site sensor.