Start & Stop

1.  Preparation before start

1.1  Pump priming

 Notice: For first start of the pump, you must fill the pump with medium. At the same time, it provides the pump with closed suction capacity. Dry running of the pump is not allowed!

 

Before pump priming, if the medium used for pump test (refer to the performance test report) is not compatible with the pumping medium in chemical properties, the operator shall carefully and completely clean the pump. Pump priming shall be made through casing hole or outlet pipe until the air is emitted by the medium. Priming height must ensure the suction side can be adequately covered before and during the running of the pump.

After long time period of storage of the pump(medium inside the pump totally evaporates) , or after repair, pump priming shall be repeated.

After pump priming, the pump works in the form of self-suction.

At discharge of pump and system, dangerous or hazardous liquid and gas escaping must be safely collected and disposed.

 

1.2   Rotating direction control

Driving motor rotating direction shall be identical to that indicated by rotating direction arrow on the pump. You can open inlet and outlet valves to instantaneously turn on the motor in order to check the rotating direction. If the rotating direction is wrong, the pump will have no suction force and will be damaged. Rotating direction of three-phase motor can be changed through exchanging any two phases of the power supply.

 If you must check pump rotating direction before pump priming, the pump shall be disconnected from the driving motor.

 

1.3  Turn on all auxiliary devices

Before pump start, if the pump has part of auxiliary devices, all heating/cooling/washing/pressure relief systems must be put into operation.

Reminder: Ensure flow/temperature /and pressure are in compliance with those in order data form or follow the operating instructions of the manufacturer.

 

2.   Start

2.1   Start

Prior to start, all switch devices on the pump suction side and pressure side shall be completely opened.

For the pump with built-in pressure relief valve, take-off pressure of the safety valve is generally set to +10% of working pressure; yet, As long as the pressure pipe has cut-off valve or has the possibility of clogging which can lead to pressure boosting, the pressure relief valve must be installed.

In start, vent valve installed at the system outlet side be must be opened until air at the pump suction side are totally emitted: Close this valve once the liquid overflows. As the pump is self-suction type, automatic air exhaust occurs without back pressure.

Check the liquid level in the storage tank. When the system runs, this liquid level can not be lower than the minimum limit; otherwise, add the liquid to the demand amount.

 

2.2    Driving

Turn on the electromotor.

 Notice: Note driving characteristics related to the product. Refer to the operating instructions of the motor manufacturer.

 

2.3   Check operational parameters

When the motor reaches its working rotating speed, use the vacuum gauge and pressure gauge to measure inlet pressure and pump outlet pressure.

Motor shall not be over-loaded. Shaft power can be checked with an amperemeter. In this case, temperature and viscosity of conveying liquid shall be checked. Compare their values with those in the order data form or acceptance records.

 Notice If pressure error is increased, it may be because the medium leaks to the suction side (circulation) from the discharge side through the assembled safety valve. Circulation leads to medium temperature rise. Pressure deviation and temperature rise can be measured with the pressure gauge and thermometer. Immediately find out the reason and eliminate it to avoid damages to the pump due to overheating and viscosity reduction.

 

3.  Stop

3.1  Stop

Close the electromotor and confirm that pump stably stops.

If the outlet pipe is equipped with the check valve, the cut-off valve can be opened; otherwise, close it.

Stop relevant auxiliary devices (such as: heating/cooling/washing systems).

 

3.2  Measures taken for long time period of stop

In case of long time period of interruption of working, the pump shall be emptied through the connecting pipe on the casing and then shall be sealed for storage (refer to section 5 in Chapter Ⅲ).

 Ensure that the discharged liquid can be disposed in a safe and environment-friendly method.