WEL Pump congratulates China aircraft carrier on its first step into water

WEL Pump hereby congratulates our national aircraft carrier on its first step into water.

It is reported that on April 26, the diving ceremony of the second aircraft carrier manufactured in China is held in the morning at Dalian Shipyard belonging to China Shipbuilding Industry Group. Fan Changlong, the member of the political bureau of China Communist Party’s Central Committee as well as the vice president of Central Military Committee attended the ceremony and made a speech.

At about 9 am, the ceremony began with the magnificent national anthem. Following international conventions, bottle-throwing rite is carried out after ribbon-cutting. On the smash of a bottle of champagne at the head of the aircraft carrier, gorgeous strips of colors are ejected from the two sides of the carrier, along with the ringing sirens sent out from all ships around. Attendees on site applauded warmly. The aircraft carrier is slowly pulled out of the dock and wharfed.

The second aircraft carrier is developed and manufactured by our country independently.The building of this carrier is started in November, 2013. In March 2015, it started to be built inside the dock.   By far, the main ship body of the aircraft carrier has been completely built up. The equipment of main systems such as power system and electric system have been installed properly. Getting out of dock and entering water is an important point of the construction of aircraft carrier, marking the staged achievement of aircraft carriers designed and built independently by our country. Next, as planned, this aircraft carrier will take system equipment debugging and fitting-out construction, followed by a full range of mooring test.

Leaders from the navy and China Shipbuilding Industry Group, Shen Jinlong, Miao Hua and Hu Wenming as well as leaders, researchers, staffs from relevant navy and local departments and representatives of officials and soliders who have took part in the construction all attended this ceremony.

WEL Pump would like to express our sincere congratulations to the success of the second aircraft.

Inspection before starting deep well submersible pump 2 inch diameter

Generally speaking, before we start the deep well submersible pump 2 inch diameter, we should make the following inspections.

Inspection and treatment of parts and accessories  

1) Clean and check the shaft bearing. Change the bearing if its clearance has obviously become larger, if the bearing roller is broken or dotted, or if the roller path is severely worn out.  During the installation of shaft bearing, the lubricating grease should take up half or one third of the space in bearing body.  

2) Check the wearing condition of impellers and sealing ring.  If the bearing wear has surpassed 3 to 5 times of the designed clearance, you should change the bearing.  

3) Check the packing sleeve. If the depth of grinding crack has reached 0.1-0.2mm or the packing sleeve is severely corroded, you should repair or change it.

4) Change the packing plate, the padding, the ineffective O shaped seal ring and the elastic sheath on the elastic pin.  

5) Check the wearing condition and the cavitation erosion condition of impeller vanes and coverplate. Repair or change it when necessary.   

6) Check the wearing condition of the mechanical seal. Make sure if it is necessary to change the mechanical seal. 

7) Change the fastenings that are badly corroded or damaged.   When you have finished reassembling the pump, you should debug it again.

Stainless steel material, good quality speaks for itself.

Tight sealing

The deep well submersible pump adopts dual-seal motor. With optimized design, the seal system is safe and reliable.

High efficiency and energy-saving

The deep well submersible pump 2 inch diameter has new floating impellers, with no axial force, better performance.

Better universality

The heads and motors of APK submersible pumps are in uniformed sizes and match well. They can be exchanged freely in installation.

Longer service life

The deep well submersible pump adopts fully oil-immersed copper wire motor that has high efficiency, longer service life and is not easy to get burned.

Failures and solutions for deep submersible well pumps

Failure	Cause	Solution
The deep submersible well pump sends out no water or not enough water	1. You didn’t fill enough water into the pump before it starts. As a result, there is stagnant air left inside. 2. The suction pipe and the packing part leaks air. 3. The pump rotates in a wrong direction. 4. The rotation speed of the pump is too low. 5. Something clogs the bottom valve, the pipeline or the inlet of impellers. 6. The water level at pump inlet drops down. 7. The impeller or the seal ring is badly worn. 8. Spiral occurs on water surface, bringing air into the pump.	1. Go on to add water into the deep submersible well pump or exhaust the air inside. 2. Block the leaking point, press the packing to make it tight enough. 3. Change the rotation direction of the motor. 4. Accelerate rotation speed. 5. Check the pipeline, remove the sundries. 6. Calculate the suction height, reduce resistance in pipeline, and increase the water level at pump inlet. 7. Change the impeller and the sealing ring. 8. Make the inlet of suction pipe deeper under water.
The water pump doesn’t run when you start it, or its shaft power is too large when it has been started.	1. The packing is pressed too tightly. Pump shaft is bent. 2. Clearance between the motor coupling and the pump coupling is so small that the two couplings interfere with each other. 3. Voltage too low. 4. The density of the fluids being transported is extensively larger than the designed fluids density. 5. Flow quantity too large, well beyond the designed range.	1. Loosen the packing gland a little, straighten the pump shaft. 2. Adjust to enlarge the clearance between motor coupling and pump coupling. 3. Check the electric circuit. 4. Change for a motor of larger power. 5. Close down the sluice valve a little or cut the impeller to reduce its diameter.
Vibration or noise beyond index	1. The ground bolt is loose. The deep submersible well pump seat is not completely grouted. 2. The pump shaft and the motor shaft are totally not coaxial or the pump shaft is bent. 3. Pump cavitation 4. Shaft bearing damaged. 5. The seal ring rubs against the impeller. 6. The rotor is totally unbalanced.	1. Tighten the ground bolt. Grout the pump seat. 2. Adjust to make the pump shaft and the motor shaft coaxial. Straighten the pump shaft or change it. 3. Bring down suction height, reduce the loss of pump head, and decrease fluid temperature. 4. Change the shaft bearing. 5. Dismantle the pump for inspection; change the seal ring or the impeller. 6. Test the rotor for balance again.
Shaft bearing too hot	1. No lubricating grease or too much lubricating grease inside the shaft bearing. 2. The shaft bearing is damaged. 3. The pump shaft and the motor shaft are totally not coaxial.	1. Add lubricating grease or remove the extra lubricating grease. 2. Change the shaft bearing. 3. Adjust to make the pump shaft and the motor shaft coaxial.
Motor too hot	1. The flow quantity is too large and the pump is working beyond its rated power. 2. The rotation speed is higher than the rated value. 3. The motor or pump head is mechanically damaged. 4. The motor runs with two phases.	1. Close down the sluice valve for water outlet properly. 2. Check the electric circuit and the motor. 3. Check the motor and the water pump. 4. Check the power source.
Mechanical seal leaks water	1. The mechanical seal is damaged or has become ineffective. 2. The mechanical seal is not installed correctly. 3. The fluids being pumped contain small solid particles.	1. Change the mechanical seal. 2. Reinstall the mechanical seal. 3. Clarify the fluids to be pumped.

Deep submersible well pump maintenance and inspection

Deep well submersible well pump 

Notes during the period when the pump is not working.  

1) Drain the stagnant liquid inside the pump.  In pump houses with no heating system, when the pump stops working in winter, you should pay attention to prevent it from frost cracking.  

2) Wipe and clean the surface of pump head and pump motor. Smear anti-rust oil on surfaces that will not be used for a long time to prevent rusting.  

3) If the pump, including standby pumps, is not used for a long time, you should start it less than every 30 days and let it run for 10 minutes to prevent internal rusting, which would otherwise make the pump fail to run. 

deep submersible well pump maintenance and inspection

Generally, you should overhaul the pumping unit once every year to replace the worn-out parts and ineffective parts.  You should disassemble the pumping unit in order in a correct way to prevent unnecessary damage caused by improper disassembly methods. 

Deep submersible well pump disassembly

1) First, take down the elastic pin, replace ineffective elastic rubber sheath.    

2) Pull out the locating pin, use crow bar to dismantle the pump lid. You must not directly pull up the pump lid only with the hoist.  

3) Make full advantage of the jackscrew to disassemble the shaft bearing.  

4) When dismantling the shaft bearing, you should screw the loop bolts into the holes on the bearing gland. Use lama or other special tools to disassemble the bearing and bearing gland together.  

5) If you need to hoist up the whole rotor, do remember to loosen the gland of mechanical seal first to separate friction pairs of the dynamic ring and the static ring. Otherwise, you may damage the end faces of friction pairs.

If you have any question, please feel free to contact info@welpump.com.

Notes for 2 inch submersible deep well pump operation

When the 2 inch submersible deep well pump is running, you should make the following checks.

1) Inspect motor temperature. The temperature of motor shaft shall not surpass 95 centigrade degree, measured by thermometer. The temperature rise (resistance method) of motor stator winding shall not surpass 800 K, provided that the surroundings temperature is not higher than 40 centigrade degree and it is not higher than 1000m above sea level.   

2) Check the temperature of the shaft bearing of water pump  If there is no oil or too much oil inside the bearing cavity, the bearing temperature will rise.  The bearing temperature generally should not rise to more than 400 k above environment temperature. The maximum temperature of shaft bearing shall not be higher than 80 centigrade degree.  If neither temperature meter nor measuring instrument is available, you can feel the temperature with hand and make judgment according to your experience.  If the pump case feels roasting hot and your hand cannot stay on it even for seconds, you should stop the pump for inspection.  

3) If abnormal noise or vibration is detected during operation, you should stop the pump immediately for inspection. It can be started again only after the problem has been found and solved.  

4) Check if the bearing leaks oil. If so, deal with the trouble timely.    8) Don’t increase the rotation speed of the pump casually. Otherwise, accidents may happen because the pump doesn’t have enough mechanical strength. But you can decrease its speed, as long as its pressure and flow quantity meet site requirements.  

5) Keep an operation diary, including records of operation date, pressure, electric current, voltage, vibration, noise, bearing temperature, shaft seal leakage, failures and problem solutions, etc.

Notes for stopping the 2 inch submersible deep well pump

1) Before stopping the pump, turn off the sluice valve for water outlet first and then turn off the pressure meter. 

2) Return all control system, protective system, devices, instruments, meters and so on back to their original status. Note if anything is abnormal.  

3) If the power is cut off suddenly during operation, you should turn off the power supply switch and the sluice valve for water outlet immediately. 

Operation notes for submersible pump deep well

Change the opening degree of sluice valve at pump outlet to adjust the pressure and flow quantity at pump outlet, make sure the pumping unit runs in high efficiency range, i.e., the range between large flow quantity point and small flow quantity point.  Note: the actual head of the pump equals to the pressure at outlet minus the pressure at inlet.  The pumping unit is proved to have no hydraulic performance problems, as long as the pressure and flow quantity of the submersible pump deep well conform to the designed working conditions, and the motor doesn’t work with overload. As for whether it meets the requirements on site, that depends on model selection.

Points of observation and check during test run  

1) Check if pump head, pump flow quantity (through flow meter) and motor electric current conform to the requirements of design. 

2) Check if the noise and vibration of the pumping unit conform to standard regulations. 

3) Check the temperature and temperature rise of the shaft bearing. 

4) Check if the shaft seal leaks. 

Notes for the submersible pump deep well when it formally starts running  

1) Note if the reading of ampere meter surpasses the rated electric current of the motor. Stop the pump timely for inspection if the reading is too high or too low.  

2) Check if the packing chamber becomes hot, if it leaks water normally.  Normally, it should leak water drop by drop continuously. You can control leakage by adjusting the nuts on packing gland.  When the packing is worn out and too much water is leaking, you should supplement the packing or replace it timely.  If there is too little or no water leakage, you should check if something blocks the back flow hole (built-in type) in pump gland or the external water supply pipeline. 

3) Check the leakage amount of the mechanical seal. It is normal if the leakage amount is lower than 5ml/h.  If you have no measuring cup, you can eyeball the amount of water drops. 8 to 10 drops per min is normal.

Installation instruction from deep well submersible pump manufacturers

These are the notes for operation many deep well submersible pump manufacturers usually offer.

Notes for test run

After installation and adjustment, the pumping unit can take a test run. Before the test run, you should do the following work.

1) After confirming that the pump head and the pump motor are coaxial, turn the coupling with hand to feel its force and hear its sound. Normally, there should be no abnormal sound and the force should be even. Check if everything is normal with the pump head and the pump motor. For example, some rotary parts may become loose and fall off; something may clog some parts of the pump; the pump freezes inside; the packing or mechanical seal is too tight or too loose; the shaft bearing is short of lubricating oil or the shaft bends, etc.

2) Check if the power supply system, power source switch, meters, circuits and other relative equipment are intact and normal.

3) Open the sluice valve, if there is a sluice valve, for water inlet completely. At the same time, close the sluice valve for water outlet and the pressure meter. Fill the pump with water. If the pump has no bottom valve, we can create vacuum inside for the sake of filling water.

4) Loosen the screw for air bleeding on the pump gland to exhaust all the air possibly remaining inside, and then tighten the screw again.

5) Check again if all bolts on the pumping unit are ok.

6) Check if the conditions for water inflow have been met, such as the height of inflow water surface, the pressure at pump inlet, etc.

7) When all relative facilities have been confirmed normal, you can start the motor. The working stuff shall not stay too close to the motor when it is starting. The motor should not run for a time longer than 2 to 3 minutes when the sluice valve for water outflow is closed. Otherwise, if it runs for too long, the liquid inside the pump will become hot, which is easy to cause an accident. Switch on the pressure meter, and gradually open the sluice valve for water outflow. By then, the reading on pressure meter at pump outlet should gradually goes down while the flow quantity and working electric current gradually rises up.

WEL pump is one of the deep well submersible pump manufacturers. We feel glad if the knowledge we share can be helpful to you. For more information, please contact info@welpump.com.