The DYFJ-C800 type valve testing bench is a fourth-generation pressure testing and inspection device independently developed by Duojia Hydraulics, based on years of production experience and in accordance with national standards and specifications.

The DYFJ-C800 valve test bench integrates mechanical, hydraulic systems, pressure testing, and the storage and recycling of liquid media into one unit, featuring complete functions, stable performance, and high degree of automation. It is widely used for the sealing face leakage testing and shell strength (pinhole) testing of various high, medium, and low-pressure valves with nominal bore sizes of 400-800mm, in the form of direct-connection flanges. Test media: water, gas, oil.

The equipment is fully powered by hydraulic drive and electrical control, with no external forces affecting the valve's test results. This significantly enhances work efficiency and reduces labor intensity, making it the ideal next-generation pressure testing equipment for valve manufacturing companies, users, and maintenance units.

DYFJ-C800 type valve test bench working principle and structure

The DYFJ-C800 valve test bench operates by using valve flange positioning and a live pawl to clamp the back of the flange, ensuring no external forces that could affect test results, in compliance with national standards for valve testing requirements.

Equipment is generally divided into hydraulic pressure supply systems, electrical control systems, water circulation systems, and various operating devices.

The equipment features a diving double-tilt design. Each workbench has a sealed blind plate for sealing, with the left workbench equipped with an in/out mechanism directly driven by a hydraulic cylinder, ensuring uniform force distribution on the valve sealing surface and reliable tightness. Both left and right workbenches can be tilted 90 degrees, and the entire workbench surface can be submerged into the external water tank, allowing the tested valve to be fully immersed in water. This facilitates the inspection of the air-tightness test and observation of the valve sealing surface, with features such as good performance and simple, compact structure.

Technical Specifications

Operation Instructions

1. Valve Mounting Method

Select a valve with the nominal bore size 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 movable 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 it tightly adheres 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 sliding bracket on the left moves towards the right fixed workbench. The other end of the valve being tested is tightly pressed against the right pressure test blank flange, aligned with the central empty space. Radially move the clamping jaws close to the valve flange. Axially move the clamping jaws to ensure they tightly adhere to the back of the valve flange. At this point, the valve should be securely held and fixed by the right-side clamping system, with the valve overall in a horizontal position.

2. Water Pressure Testing Methods (Bi-directional Inflow, Drainage)

After the valve fixture 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 inlets, left and right water inlets, close the air intake, drain, and exhaust valves. Start the low-pressure water pump, observe the movement of the water pressure gauge pointer. When the pointer stops rising, it indicates the valve cavity is fully filled with water. Start the high-pressure water pump; the pump will automatically stop when the water pressure reaches the pressure set on the electrical contact pressure gauge, and the equipment will enter a water pressure maintenance state.

Upon reaching the pressure-holding time, the valve shows no issues. First, open the water valve to release the pressure inside the valve chamber, then remove the valve.

3. Pressure Test 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 mount is completed (for example, using pressure air, usually not exceeding 10 kg), open the inlet and air inlet valves, and close the outlet and air outlet valves. Close the inlet and air inlet valves when the pressure gauge reaches the highest pressure, and the equipment is in a pressure maintenance state.

Upon reaching the pressure-holding time, there are no issues with the valve. First, open the vent valve to release the pressure inside the valve chamber, then remove the valve.

Use Instructions and Requirements

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

2. Use 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 gauge's lower limit. 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 inhibitor to the recirculating water, and replace it 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 maintain clean and smooth operation.

6. Operators must undergo professional training before starting work, adhere to standardized procedures, and prioritize safety.