Various chemical pump installation essentials and problem solving skills! Mechanical properties of carbon steel commonly used in valves

Various chemical pump installation essentials and problem solving skills! Mechanical properties of carbon steel commonly used in valves

Precautions for water pump installation
The installation position of the water pump must be appropriate, the height of the water pump should be able to make the pump inhale enough vacuum, the installation position of the water pump must be level and stable, so as to achieve the maximum working efficiency of the water pump, if the pump and the power machine is connected with the shaft must ensure that the shaft is in the same straight line, so as to avoid the pump vibration and bearing friction on one side of the wear. When the belt drives the impeller to rotate, the belt should be good, some pump room there are many pumps, then to maintain the direct distance of the pump, each pump must be stable to prevent the pump work will move position collision. In the pump suction pipe must be sealed, do not use elbow, because it is easy to leak to reduce the amount of water pumped. If it is a submersible pump, the position in the water must be properly placed in the water source is relatively deep, can dig a pit in the water alone, so as to ensure that there is enough water can be transported out, and to ensure that there is no silt, otherwise it will cause the blockage of the pump.
Water pump in the process of use will inevitably appear some failures, for different pumps have different treatment methods.
1. The water pump fails to produce water
The pump does not produce water. It may be that the pump is broken, or there is no water in the pump. The water level of the water source will also be low. Check the whole pump at this time, fill the pump with diversion water, put the pump below the water level. If the pump is determined to be broken, it should be repaired in time.
2. The water pump vibrates violently
The reason for this situation is that the pump is not fixed firmly, if the pump in accordance with the height is too high will also produce vibration. There is also a possibility that the pump bearing and the motor bearing are not in the same straight line, which will cause the imbalance of the pump to produce vibration.
3. The traffic is small
When the pump suddenly appears the flow is very small is likely to be the suction pipe leakage, or the bottom valve leakage, when the water supply is not enough, this will happen, if the pump seal ring wear will also cause such a situation, then to check the suction pipe to see whether the leakage, if the leakage should be blocked. If it is silt into the pump to clean out the mud in the pump. It is also possible that the pump bearing is worn too much at this time to replace the new bearing.
Pump installation requirements:
1, the water pump should be installed in a ventilated place, outdoor installation should add protective cover, to avoid sun exposure and rain
2. The installation height should be less than the allowable suction vacuum height minus the loss of the water inlet pipe. Under standard conditions, the installation height is 10.3- (NPSH) r-0.5-hw, indicating hydraulic loss of suction line
3, the pump outlet flange should be installed on the pressure gauge, in order to observe and control the pump operating conditions, pipeline weight shall not be borne by the pump
Installation of pump:
1. Before installation, check whether it is deformed or damaged during transportation, and whether fasteners are loose or fall off.
2, installation and configuration of inlet and outlet pipe: pipe installation should be as far as possible to reduce the pipeline fluid resistance as the principle. After water inlet pipe should be added filter screen, to prevent hard impurities or hard solid particles into the pump cavity damage shaft seal or water leaf, resulting in water pump leakage or abnormal: check valve should be added at the inlet pipe, in order to facilitate water injection;
3, wiring: must be according to the nameplate requirements of the correct wiring, wiring, the terminal must be firm, not allowed to loose, otherwise, it will cause poor contact and lead to lack of phase burning machine. The overload protection device must be used on the wiring line, and adjust the setting value of the protection device according to the current requirements on the motor nameplate;
4, according to the rotation method: vertical pump; Horizontal pump directly take over the installation.
5, suction water level is higher than the pump: single pump and double pump can be used in series or parallel;
6, suction water level is lower than the pump: such as pool pumping water;
Start of pump:
1. Before starting the pump, open the inlet gate valve and pump exhaust valve plug, and close the outlet gate valve. The pump chamber is filled with water to enable the pump to start normally:
2, point the motor, from the motor end, check whether the steering is in line with the direction shown by the arrow.
Operation of pump:
1. After the pump starts, gradually open the outlet gate valve and adjust it to the required working condition;
2. During the operation of the pump, the flow rate of the running condition point is not greater than the flow rate of the large flow point given in the performance reference table, and the current of the motor shall not exceed the rated current during operation;
3. Stop sequence: close the gate valve motor pressure gauge on the outlet pipe.
Pump maintenance:
1, should often check the pump in the process of operation is smooth. There is no mechanical seal wear and leakage, timely replacement of seals, to prevent pressure water into the motor;
2. Frequently check the temperature change of the motor housing. The high temperature should not exceed 85 degrees Celsius.
3. When the pump is out of use for a long time, the water should be drained, the rust scale should be removed, and the rust grease should be coated, so that it can be used again next time.
Working principle:
Diaphragm pumps are driven by compressed air. Directional air distribution valve and guide valve, called: air chamber, are arranged in the central part of the pump. The medium flows through two confluence tubes and an outer diaphragm chamber, called the medium chamber. Usually check valves (ball or disc) are arranged at the top or bottom of each outer diaphragm chamber or share a confluence tube. The two outer diaphragm chambers are connected by the suction and outlet joints, and the pump is self-priming. In operation, air distribution valves alternately control the pressurization of each diaphragm. After each stroke, the valve will automatically change the position, so that the air can be switched to another diaphragm chamber, so that the two sides of the diaphragm chamber to form alternate suction and pressure feeding stroke, diaphragm in parallel to move in the path, the air valve no oil lubricating oil demand, this is the preferred operation mode; Clean, dry air can improve pump performance.
Air valve
The check valve opens and closes as the medium passes through the pump. This allows each outer diaphragm chamber to be filled and discharged alternately. The check valve responds to pressure differences. Ball check valves can handle media containing small particles, while disc check valves can handle media containing soft particles close to the diameter of the pipe. When the air distribution valve makes the compressed air enter the left diaphragm chamber, the diaphragm is pressed out, and the pressure feed stroke is formed. The medium in the pressure feed department is forced to leave the left outer diaphragm chamber, the check valve and the confluence tube, and then flows out from the outlet of the pump. The outlet position can be the top, the bottom, or the side. When the left diaphragm chamber is pushed out under pressure, the diaphragm connecting rod internally drags the right diaphragm inward retracted check valve to fill with fluid. After this circulating action is completed, the air distribution valve will automatically change its position, so that the air will be switched to another diaphragm chamber, and the above circulating action will be repeated in reverse, that is, the diaphragm chambers on both sides will therefore present alternating pressure feeding and liquid absorption action.
Installation and startup
The pump is placed as close to the product as possible, so that the suction line is short, the number of configuration parts is reduced, do not reduce the pipeline specifications.
To extend diaphragm life, keep the pump as close to the fluid being pumped as possible, and install a slow pressure adjustment device to extend diaphragm life when inlet pressure exceeds 10 ft (3 m) column.
If hard piping is installed, use a short hose connection between the pump and the pipe. Hoses can slow vibrations and distortions in the pipe, and a pressure stabilizer is recommended to further reduce pulses in the fluid.
Gas supply
The gas supply pressure shall not exceed 125PSI (8.6BAR) for metal pumps and 100PSI (6.9BAR) for plastic pumps. Connect the pump air inlet to the air source with sufficient capacity and pressure to meet the design requirements. If the gas supply line is a hard pipe, connect a short hose between the pump and the pipe to reduce distortion. In addition to the air intake cap, the weight of the air intake pipe and pressure regulating filter must also be supported in some way. If the pipe is not supported, it may damage the pump. A pressure regulating valve must be installed to ensure that the supply pressure does not exceed the specified range.
Instructions Before Operation
Before the pump works, check all the fixed objects to prevent slack, tighten the loose place to avoid leakage, and fix with the method described in the card attached with the pump.
Intake and start
When starting, open the air valve about 1/2 to 3/4 turns. After the pump starts, open the air valve to increase the air flow to achieve the required flow.
exhaust
If the diaphragm is broken, the extracted liquid or gas will enter the air port of the pump and be discharged into the atmosphere. When dangerous or toxic substances are extracted, it needs to be piped to a suitable place for safe disposal.
If the pump is sunk into the liquid operation, the gas should be discharged from the liquid surface, and the exhaust pipe should not be less than 1 “(2.45CM). Reducing the size of the exhaust pipe limits the gas flow and reduces the pump utilization. When the material level is higher than the pump, the outlet should be in a higher place to prevent siphon phenomenon.
At a certain temperature and humidity, the expelled gas may freeze, and the use of gas drying can eliminate most of these problems.
After use
If used to transport easily cured substances, in order to prevent pump damage, after each use to thoroughly clean the pump. After use, the product left in the pump dries out or sticks to the pump, which can cause diaphragm and valve problems before the next start. In freezing temperatures, the pump must be drained after use in any case.
Notes on valve lubrication
Pump air distribution valve and guide valve are designed in accordance with no lubricating oil, this is the ideal working state. In some cases, such as personal hobbies or very poor air quality, the compressed air supply can also be lubricated, the compressed air supply system properly lubricated, the pump air system can work with appropriate lubrication requires the use of an air line lubricator, set to pump the air every 20SCFM to deliver a drop of cleaner oil, Can query pump performance curve open quantitative. Mechanical properties of carbon steel commonly used in valves