The DYFJ-A800 valve testing bench is the fourth-generation pressure testing and inspection equipment independently developed by Duojia Hydraulic Company, based on many years of production experience and in accordance with national standards and specifications.

The DYFJ-A800 type valve test bench integrates mechanical and electrical systems, hydraulic systems, pressure testing, and storage and recycling of liquid media into one unit, featuring complete functions, stable performance, and high level of automation. It is widely used for sealing face leakage testing of various high, medium, and low-pressure valves with nominal diameters of 400-800mm, as well as performance testing such as shell strength (sand holes). Test media: water, gas, oil.

The equipment is hydraulically driven and electrically controlled throughout the process, exerting no external force on the valves that could affect test results, significantly enhancing work efficiency and reducing labor intensity. It is the ideal next-generation valve pressure testing equipment for valve manufacturing enterprises, users, and maintenance units.

DYFJ-A800 Type Valve Test Bench Working Principle and Structure

The DYFJ-A800 type valve test bench operates by positioning the valve flange and clamping the back of the flange with a live paw, ensuring no external forces that could affect the test results during valve testing, in compliance with national standard valve testing requirements.

The equipment is broadly categorized into hydraulic pressure supply systems, electrical control systems, water circulation systems, and various operating devices.

The equipment is in a horizontal clamp pressure design, with each side of the workbench sealed with a blind plate. The left workbench is equipped with a reciprocating mechanism, directly driven by a hydraulic cylinder to ensure even force distribution on the valve sealing surface for reliable clamping. (Left) The right workbench can be flipped 90 degrees for convenient checking of gas-sealing tests and observation of the valve sealing surface, featuring good performance and a simple, compact structure.

Operation Instructions

1. Valve Mounting Method

Select a valve with a nominal bore size corresponding to 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 actuating clamp to exceed the outer diameter of the valve flange. Extend the clamp 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 opening. Radially move the clamp close to the valve flange. Axially move the clamp to ensure the clamp is tightly against the back of the valve flange. At this point, the valve should be securely held and fixed by the left-hand clamping system, ensuring the valve does not fall off.

The sliding bracket moves to the right fixed workbench, the other end of the valve to be tested is tightly sealed against the right pressure test blank flange, aligned with the center opening. Radially move the clamping jaws close to the valve flange; axially move the jaws to ensure they are flush against the back of the valve flange. At this point, the valve should be securely held by the right-side clamping system, with the valve in a horizontal position overall.

2. Water Pressure Testing Methods (Bidirectional Inflow and Drainage)

After the valve mount is completed, refer to the "Clamping Cylinder Pressure Reference Table" to increase the hydraulic clamp's gripping 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 inlet, drain, and vent 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; the high-pressure water pump will automatically stop when the water pressure reaches the pressure set on the electrical contact pressure gauge. The equipment then enters the water pressure maintenance state.

Upon reaching the pressure-holding time, the valve is free of any issues. First, open the water valve to relieve the pressure inside the valve chamber, and then remove the valve.

3. Pressure Testing Methods (Bi-directional Inlet, Exhaust)

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 mount is completed (using pressure air as an example, usually not exceeding 10 kg), open the inlet and air inlet valves, and close the drain and air vent valves. Close the inlet and air inlet valves when the pressure gauge reaches the highest pressure, and the equipment remains in a pressure-holding state.

Upon reaching the pressure-holding time, the valve is problem-free. First, open the exhaust valve to release the pressure inside the valve chamber, then remove the valve.

Handling Instructions and Requirements

1. Align the equipment horizontally during installation or secure the anchor slot steel with concrete.

2. Choose 46-grade anti-wear hydraulic oil (use anti-freeze 46-grade anti-wear hydraulic oil below 0℃), ensuring the oil level does not fall below the indicator. Regularly check the oil level and hydraulic oil. After one year of use, clean the oil tank and replace the hydraulic oil.

3. Add rust prevention powder to the recirculating water and change the water promptly when the water quality deteriorates.

4. The equipment worktop should be kept clean, and there should be no debris between the test valve flange and the test pressure blanking plate.

5. Add lubricant to all moving parts of the testing bench to ensure clean and smooth operation.

6. Operators must undergo professional training before taking their posts, adhere to standard procedures, and prioritize safety.