The DYFJ-A500 valve testing bench is the fourth-generation pressure testing and inspection equipment independently developed by Duojia Hydraulics, based on years of production experience and in accordance with national standards and specifications.
The DYFJ-A500 valve test bench integrates mechanical and electrical systems, hydraulic systems, pressure testing, and the storage and recycling of liquid mediums into one unit, featuring comprehensive functions, stable performance, and high degree of automation. It is widely used for sealing surface leakage testing and various performance tests such as shell strength (pinhole) on straight-through flanged high, medium, and low-pressure valves with nominal bore sizes of 250-500mm. Test mediums: water, gas, oil.
The equipment is driven and controlled by hydraulics and electricity, exerting no additional external force on the valves that could affect test results. This significantly enhances work efficiency and reduces labor intensity, making it the ideal new generation pressure testing equipment for valve manufacturing companies, users, and maintenance units.
DYFJ-A500 Type Valve Test Bench Working Principle and Structure
The DYFJ-A500 valve test bench operates by positioning the valve flange and clamping the back of the flange with live claws, ensuring no external forces affect the test results, in compliance with national standards for valve testing requirements.
Equipment is broadly categorized into hydraulic pressure supply systems, electrical control systems, water circulation systems, and various operating devices.
The equipment features a horizontal clamp pressure design. Both the left and right workbenches are sealed with blind plates. The left workbench is equipped with a reciprocating mechanism, directly driven by a hydraulic cylinder, ensuring even force distribution on the valve sealing surface for reliable clamping. (Left) The right workbench can be flipped 90 degrees for easy inspection of gas sealing tests and observation of the valve sealing surface, with features such as good performance and simple, compact structure.
Operation Instructions
1. Valve Mounting Method
Select a valve with a nominal bore that matches the equipment model, turn on the power, and start the hydraulic system. Move the left-hand carriage back to a position longer than the valve being tested. Radially move the clamping jaws to exceed the outer diameter of the valve flange. Extend the clamping jaws axially to exceed the thickness of the valve flange. Place the valve flange face tightly against the left-hand workbench test blind plate, aligning with the center hole. Radially move the clamping jaws close to the valve flange, and axially move the clamping jaws to make them tightly adhere to the back of the valve flange. At this point, the valve should be securely clamped and fixed by the left-hand clamping system, ensuring the valve does not fall off.
The left-hand moving bracket advances to the right-hand fixed workbench. The other end of the valve to be tested is tightly pressed against the right-hand pressure test blank flange, aligned with the center opening. Radially move the clamping jaws close to the valve flange. Axially move the clamping jaws to make the jaws tightly adhere to the back of the valve flange. At this point, the valve should be securely held and fixed by the right-hand clamping system, with the valve in an overall horizontal position.
2. Water Pressure Testing Methods (Bi-directional Inflow and Drainage)
After the valve clamp is in place, refer to the "Clamping Cylinder Pressure Reference Table" to increase the hydraulic clamp force to the required pressure. Adjust the electrical contact pressure gauge (for a 25 kg valve, adjust the pointer to 2.5 MPa). Open the main water inlet, left, and right water inlet valves, close the air intake, and release water and air valves. Start the low-pressure water pump, observe the movement of the water pressure gauge pointer. When the pointer stops rising, it indicates that the valve cavity is fully filled with water. Start the high-pressure water pump, and it will automatically stop when the water pressure reaches the set pressure on the electrical contact pressure gauge. The equipment then enters the water pressure holding state.
Upon reaching the pressure holding time, the valve has no issues. First, open the water drain valve to relieve the pressure inside the valve chamber, and then remove the valve.
3. Pressure Testing Methods (Bi-directional Intake, Venting)
The equipment does not come with a gas source. The user must provide a separate gas source. Please consult the manufacturer before using high-pressure gases.
After the valve mounting is complete (for example, using compressed air, generally not exceeding 10 kg of pressure), open the water and air intake valves, and close the water and air release valves. Close the water and air intake valves when the pressure gauge reaches the maximum pressure, and the equipment is in a pressure-holding state.
Upon reaching the pressure-holding time, the valve is problem-free. First, open the vent valve to release the pressure inside the valve cavity, then remove the valve.
Handling Instructions and Requirements
1. Ensure the equipment's horizontal position is adjusted or use concrete to secure the anchor槽 steel during installation.
2. Choose 46-grade anti-wear hydraulic oil (use antifreeze 46-grade anti-wear hydraulic oil below 0℃), ensuring oil level is not below the gauge's lower limit. Regularly inspect oil levels and hydraulic oil. After one year of use, clean the oil tank and replace the hydraulic oil.
3. Add rust inhibitor to the recirculating water; replace the water promptly when the water quality deteriorates.
4. The equipment work surface should be kept clean, and there should be no debris between the test valve flange and the test pressure blank flange.
5. Add lubricant to all moving parts of the test bench to ensure clean and smooth operation.
6. Operators must undergo professional training before starting work, adhere to standardized procedures, and prioritize safety.
