Use And Maintenance of Manual Pressure Testing Pumps

A manual pressure testing pump is a device widely used in various industrial fields and laboratory settings, primarily for conducting pressure tests and calibration work. The method of use is as follows:

1.Preparatory work:

Ensure that the working area of the manual pressure testing pump is dry, clean, and free from any ignition sources such as open flames.

Check the condition of the manual pressure testing pump to ensure that the pump seals, pressure gauge readings, and connection threads are free from damage or looseness.

u Connect the pressure testing pump:

Connect the pressure testing pump to the indoor water supply system via a connecting hose from the lower pipe outlet of the indoor water supply pipeline.

After installing the working nozzle and handle and filling it with the working medium, you can start using the manual pressure testing pump.

u Inject water into the pipeline:

Open the main water supply valve to fill the indoor plumbing system with water. At the same time, open the pressure test pump’s relief valve. Once the pipes are fully filled with water and the pressure test pump’s tank is also full, immediately close the main water supply valve and the pressure test pump’s relief valve.

Before the test, first fill the test container with clean test medium and remove as much air as possible.

·  Operating steps:

u Before use, check that the threaded connections are securely tightened, and apply a few drops of machine oil to the piston and the hinge pin of the handle for better lubrication.

The selected range of the pressure gauge should be 1.5 times greater than the rated pressure.For example, the manual test pump series from Bohui has a pressure range of 0 to 60 bar. Its rated pressure must be kept below 40 bar. The reason for specifying that the rated pressure should be lower than the pressure gauge’s recommended measurement range is to ensure the operator’s safety during use.

u When the handle is lifted, a vacuum is created inside the pump body, causing the inlet valve to open and allowing clean water to flow through the water filter and into the pump body via the inlet pipe. When the handle is pressed down with force, the inlet valve closes, while the outlet valve is pushed open, delivering pressurized water that enters the device under test. This process repeats continuously, enabling pressure testing at the rated pressure.

·  Precautions:

During the process, apply and release pressure slowly, ensuring that no leaks or seepage occur once the test pressure reaches the required level.If water leakage or seepage occurs during the pressure-holding phase, it indicates that the pipeline installation is substandard, and the construction personnel must conduct a thorough inspection of the pipeline installation and connections.

After the pressure test is completed, loosen the water valve to prevent damage to the pressure gauge, and drain all the water from the pump while drawing in a small amount of engine oil.

Generally, when testing pump seals with water as the test medium, NBR nitrile rubber is used.If the manual pressure testing pump uses oil as the test medium, you need to inspect the test seals and replace them with oil-resistant fluororubber or a higher-grade silicone rubber.

Generally, you should not arbitrarily switch the medium used in a manual test pump, as this could shorten the service life of the seals. If you do alternate between different media, be sure to thoroughly clean the test pump after each use—this includes the pump body, seals, and tubing. The most appropriate practice is to equip each test pump with a dedicated unit for each specific medium and avoid mixing them whenever possible.

Manual pressure testing pumps are not suitable for use in environments containing acids, alkalis, or corrosive substances.

·  Maintenance and upkeep:

· Maintenance and upkeep of manual pressure testing pumps are crucial for ensuring the equipment’s long-term stable operation, extending its service life, and guaranteeing test accuracy. Daily maintenance should focus on key aspects such as cleaning, the condition of seals, lubrication, storage environment, and regular inspections.

· Clean and drain after daily use.

· After each use, the pump must be thoroughly drained of any residual water or test medium to prevent moisture from lingering and causing internal rusting or freezing damage. This is especially important after use in winter or low-temperature environments—immediately drain and dry all metal components. At the same time, the water tank and pipelines should be rinsed with clean water; absolutely avoid using wastewater containing sediment, fibers, or impurities, as these could clog valve bodies or wear down sealing elements.

· Seal Inspection and Replacement

· The sealing elements are the core components of the pressure testing pump and directly affect its ability to maintain pressure. Regular inspections should be conducted to check whether O-rings, diaphragms, valve seat sealing surfaces, and other sealing parts have aged, deformed, or worn out. If leakage is detected, the pump fails to maintain pressure, or the pressure build-up is slow, the machine should be immediately stopped and inspected. Common sealing elements such as O-rings can be replaced according to their specifications (e.g., Φ16×2.4). If the valve seat sealing surface is uneven, it can be repaired by grinding.

· Lubrication and Maintenance of Moving Parts

· The moving parts of the manual pressure testing pump—such as the handle, plunger, and linkage plate—require regular lubrication to reduce friction and prevent jamming. It is recommended to apply light-weight mechanical oil or lithium-based grease to areas like the plunger rod and handle pivot shaft. The frequency of lubrication depends on the usage rate: for high-frequency use, lubricate once a month; for low-frequency use, lubricate once every three months.

· Calibration and Inspection of Pressure Gauges and Valve Components

· The pressure gauge is the “eyes” of the pressure testing pump and should be calibrated regularly to ensure accurate readings. If the pressure gauge’s pointer fails to return to zero, jumps erratically, or displays abnormal readings, it should be replaced or sent for inspection promptly. At the same time, check whether the control valve, drain valve, relief valve, and other components are functioning smoothly and reliably, and verify that the valve needle seals properly against the valve seat, thereby preventing pressure leaks or failure to relieve pressure due to valve malfunction.

· Storage Environment and Rust Prevention Treatment

· When the pressure testing pump is not used for an extended period, it should be stored in a dry, well-ventilated environment free of corrosive gases, and protected from direct sunlight and moisture. It is recommended to apply rust-preventive oil to metal surfaces and cover the equipment with a dustproof cover. If the equipment is equipped with casters, avoid prolonged heavy loads to prevent deformation.

· Quick Troubleshooting for Common Faults

· Pressure isn't building up: Check whether the water inlet is unobstructed, whether the valve components are sealed, and whether the sealing ring is damaged.

· Pressure cannot be maintained: Focus on checking the sealing integrity of the drain valve, control valve, and connecting pipelines.

· The handle is difficult to operate: Check whether the plunger is stuck, whether lubrication is insufficient, and whether the linkage plate is loose.

· Through the systematic maintenance and upkeep described above, the reliability and safety of the manual pressure testing pump can be effectively enhanced, the failure rate can be reduced, and each test can be completed accurately and efficiently.