Overview

S. SH type pump is a single-stage, double suction, pump shell split centrifugal pump used for sucking and delivering clean water and liquids with physical and chemical properties similar to water.

When the head of this type of pump is between 9 meters and 140 meters, the flow rate is between 126 meters'/hour and 12500 meters'/hour, and the maximum temperature of the liquid should not exceed 80 ℃. It is suitable for factories, mines, urban water supply, power stations, large-scale water conservancy projects, farmland irrigation and drainage, etc. The 48SH-22 large pump can also be used as a circulating pump for thermal power plants.

The meaning of pump model: such as 10SH-13A

The diameter of the suction port is divided by 25 (i.e. the diameter of the suction port of the pump is 250 millimeters)

S. SH Double suction single-stage horizontal centrifugal clean water pump

13 is divided by 10 (i.e. the specific speed of the pump is 130)

A indicates that the pump has replaced the impeller with a different outer diameter

Structural description

S. The suction and discharge ports of the SH type pump are both located below the axis of the pump, in a horizontal direction and perpendicular to the axis. The pump cover of the pump is fixed to the pump body with double headed bolts and conical positioning screws, making it easy to open and inspect all parts inside the pump without disassembling the inlet and outlet pipelines and motors. Therefore, maintenance is extremely convenient. From the transmission direction, the SH type pump rotates counterclockwise; The S-shaped water pumps all rotate clockwise:

S. The main components of SH type pump include: pump body (1), pump cover (2), impeller (3), shaft (4), double suction sealing ring (5), shaft sleeve (6), and bearing body (14).

The pump body (1) is made of cast iron. The working chamber that forms the impeller with the pump cover has pipe screw holes for installing vacuum and pressure gauges on the flanges of the inlet and outlet channels. The lowest disposal point for the neck of the pipe is a screw hole for draining water.

The pump cover (2) is made of cast iron. There are screw holes on the upper part for installing water seal pipes and vent pipes, as well as hooks for lifting the pump cover.

The impeller (3) is made of cast iron and has a symmetrical shape with twisted blades between the two walls. Liquid enters the impeller from both sides and undergoes static balance testing during manufacturing.

Shaft (4) is made of high-quality carbon steel. The center of the shaft is the impeller, which is fixed with keys, shaft sleeves, and shaft sleeve nuts on both sides. The right end of the shaft is equipped with a coupling, which is directly connected to the motor. Belt transmission is not allowed at the coupling end. If belt transmission is required, a separate bracket must be set up to support the pulley.

Double suction sealing ring (5) is made of cast iron to prevent high-pressure water from leaking back into the inlet part of the water pump. A protruding semi-circular ring is made on the double suction sealing ring and embedded in the pump body to fix it. It is a vulnerable part and can be replaced with spare parts after wear.

The shaft sleeve (6) is made of cast iron and is used to fix the position of the impeller and protect the wear of the shaft inside the packing chamber. It is a vulnerable part and can be replaced with spare parts after wear.

S. The Sh type pump has two supports and uses a single row radial ball bearing. The bearing part A, located near one end of the coupling in the bearing body (14), and the other end, referred to as bearing part B, are lubricated with grease. Due to the complete symmetry of the impeller, theoretically, the water pump does not generate axial force. However, in manufacturing, it is difficult to achieve exactly the same gap between the water flow passing parts and the sealing ring on both sides of the water pump. Therefore, the water pump may generate axial force, which is borne by the single row radial ball bearing in part B of the bearing.

The packing plays a sealing role, preventing air from entering the pump and the leakage of large amounts of liquid. The packing seal consists of a composite packing chamber on the pump body and pump cover, a packing cover, a packing ring, a packing sleeve, and packing. A small amount of high-pressure water inside the pump cover flows into the packing chamber through the external water seal pipe (or internal water tank) and packing ring, serving as a water seal.

The tightness of the packing must be appropriate, neither too tight nor too loose, based on the ability of the liquid to leak out drop by drop. If the packing is too tight, the bearing is prone to heating and consumes power. If the packing is too loose and the liquid leaks, it will reduce the efficiency of the water pump.

1. Pump body 2. Pump cover 3. Impeller 4. Shaft 5. Double suction sealing ring 6. Shaft sleeve 7. Packing bag 8. Packing 9. Packing ring 10. Water seal pipe 11. Packing cover 12. Shaft sleeve nut 13. Fixed screw 14. Bearing body 15. Bearing body cover 16. Single row radial ball bearing 17. Round nut 18. Coupling components 19. Bearing sleeve 20. Bearing end cover 21. Key 22. Double headed bolt

Simple calculation explanation

In actual work, the outlet pressure indicated by the pressure gauge is determined by the vertical height from the pump axis to the drainage surface and the total head loss in the drainage pipeline (including all valves, elbows, and small head pipes). The vacuum degree indicated by the vacuum gauge is determined by the vertical height from the pump axis to the suction surface and the total head loss in the suction pipeline. Therefore, the sum of the vertical height from the self-priming surface to the outlet surface plus the total head loss on the suction and discharge pipelines must be within the specified working range of the pump. It is uneconomical to use it outside or below the specified working range of the pump.

The maximum allowable suction vacuum is meters of water column: at atmospheric pressure of 760 centimeters of mercury column. Under the condition of a water temperature of 20 ℃ and a certain flow rate, the maximum allowable suction vacuum degree of the water pump is. When installing the water pump, users should pay attention to the vertical height from the pump axis to the suction surface. They should subtract all the head losses in the suction pipeline (including valves, elbows, bottom valves, filters, etc.) and the influence of water temperature and atmospheric pressure on the suction vacuum degree from the maximum allowable suction vacuum degree meter of the selected water volume. From the performance table, it can be seen that when the water volume increases, the allowable suction vacuum degree is smaller, and when the water volume is small, the allowable suction vacuum degree is larger. When the water pump operates at a certain water volume, if the vacuum degree exceeds the allowable vacuum degree for that water volume, the water delivery height and water volume will change, and there is a possibility of cavitation, which has a great impact on the working life of the water pump.

At the specified standard speed, the main performance of this water pump meets the main performance listed in the technical specifications.

The markings specified in the performance standards for water pumps:

Q-flow rate (liters/second or cubic meters/hour)

H-Head (meters)

N-axis power (kilowatts, horsepower)

Efficiency (%)

N revolutions per minute

This water pump is specified with an impeller outer diameter of D, a flow rate of Q, a head of H, and a shaft power of N when the rotation speed is n. If necessary, the rotation speed can be reduced to n, or the impeller diameter can be reduced to D2 for use. At this time, the flow rate becomes Q2, the head is H2, and the shaft power is N2. The relationship between them is as follows:

Q2=Q or Q2=Q

H2=H() 2 or H2=H() 2

N2=N() 3 or N2=H() 3

The specified speed in this type of pump is the highest speed, and it is only allowed to be 4% higher than the specified speed during pump operation. If you want to increase it further, you must obtain the consent of our factory. There is no limit to reducing the speed for use.

Assembly, starting, stopping, and operation

I、 install

1. Preparation before installation:

(1) The water pump and motor should be checked for damage.

(2) Prepare tools and lifting machinery.

(3) Check the foundation of the machine according to the diagram.

2. Installation sequence:

There are two types of standardized water pumps: those with a base and those without a base. The installation principle is the same, and only the installation sequence with a base will be described here

(1) Place the base on the foundation, place iron pads near the anchor bolts, raise the base by about 20-40 millimeters, level the equipment, and fill it with cement slurry.

(2) Check the levelness of the pump seat with a spirit level, level it, tighten the anchor bolts and nuts, and fill the pump seat and anchor bolt holes with cement slurry.

(3) After 3-4 days of cement solidification, check the water level again.

(4) Remove the support surface of the pump base, the flat surface of the water pump foot and motor foot, and place the water pump and motor on the base.

(5) Adjust the level of the pump shaft (the prime mover shaft can be temporarily ignored), level it, and tighten the nut appropriately to prevent movement; After the pump end adjustment is completed, install the motor and place a pad on the feet that are not level properly.

(6) Leave a certain gap between the pump and motor coupling (refer to the assembly diagram), place a steel ruler on the coupling (observe from top to bottom, left to right), and check whether the axis of the water pump and the axis of the motor coincide. If they do not coincide, place a few thin iron plates under the foot of the motor to make the motor coupling match the steel ruler. When using several thin iron sheets, they should be removed and replaced with a whole piece of flattened pad of the same thickness, and the installation should be rechecked.

(7) To check the accuracy of installation, use a feeler gauge to measure the gap between the coupling planes at several opposite positions. The maximum and minimum gap difference between the two ends of the coupling plane on one circumference should not exceed 0.3 millimeters. The difference between the left and right centerlines of both ends shall not exceed 0.1 millimeters.

(8) After pressing the water pump pipe, the axis needs to be calibrated for the last time, as it is easy for the water pump to move when installing the pipeline.

II、 delivery pipe

1. The water pipe should have its own bracket to prevent all weight from being pressed on the pump.

2. Gate valves and check valves should be installed between the drainage pipe and the water pump (not required for heads less than 20 meters). The inner diameter of the gate valve should not be smaller than that of the pipe, and the check valve should be installed behind the gate valve.

3. The following factors should be considered for the suction pipe

① Make the pipes as short and minimize bends as possible.

② The bending of the pipe should follow the general regulations and should not be too small to avoid excessive losses.

③ The pipe should have no gas storage phenomenon, and the flange connection should be very sturdy to prevent air leakage.

④ When the water pump is installed at the water level, a bottom valve should be connected to the inlet pipe end (excluding vacuum water intake).

⑤ The suction pipe should also have its own bracket.

II、 Start and Stop

1. Clean the oil applied on the shaft and other coated bodies.

2. Clean the bearings and oil chamber with gasoline, and wipe them clean with cotton yarn or a rag.

3. Injecting calcium based grease into the bearing body of the water pump occupies 70% of the bearing body space,

4. Start the test and check if the rotation direction of the motor meets the requirements of the water pump. At this time, the coupling screws must be removed and the motor rotation direction should be attempted again to prevent reverse rotation and loosening of the shaft sleeve nut.

5. The valves, pressure gauges, and vacuum gauges on the drainage pipe should be closed.

6. For water pumps with a suction pipe diameter of less than or equal to 300 millimeters, remove the three square screw plugs on the pump cover and fill the highest hole with water. When the suction pipe diameter is greater than or equal to 350 millimeters, open 1/4 of the square screw plugs on the reducing four-way pipe, connect the vacuum pump, and start the water intake.

7. After the above process is completed, start the motor and turn on the pressure gauge.

8. When the water pump rotates normally and the pressure gauge displays the appropriate pressure, then open the vacuum gauge and gradually open the gate valve on the drainage pipeline until the required pressure is reached.

9. When stopping the water pump, slowly close the gate valve and vacuum gauge on the drainage pipeline, and then turn off the pressure gauge. If the external temperature in the environment is low, open the square screw plug at the bottom of the pump body to drain the remaining water to prevent freezing and cracking.

10. When the water pump is not used for a long time, it should be disassembled and the water on the parts should be wiped dry, and rust proof oil should be applied to the sliding surface for safekeeping.

IV、 Moving and turning

1. Pay attention to the temperature of the water pump bearings. The temperature rise of the water pump bearings should not exceed 35 ℃ of the external temperature, but the maximum should not exceed 75 ℃.

2. The oil change time for Type A water pump should be carried out after working hours for the first time, and then every 2400 hours of work or every maintenance of the water pump thereafter.

3. The normal leakage rate in the packing room is about 10-20 drops per minute. If it exceeds or is too little, the packing gland should be tightened and relaxed.

4. Regularly check the elastic coupling and pay attention to the temperature rise of the motor bearings.

5. When noise or abnormal sounds are detected during the operation process, the operation should be stopped immediately, checked, and the problem should be eliminated.

Possible faults and their solutions

S. Table 1 Operating Performance of SH Pump

3.6

S. Performance Table of SH Type Pump