How to use the water pump correctly? How to choose a water pump

Determine the design flow rate and head, as well as the diameter and type of the pump, and use the "Pump Performance Table" to select the pump model.

Check the operating status of the parts before starting the pump to ensure the safe operation of the pump to avoid accidents.

Water pump is a very widely used and varied general machinery, and it is very important to choose the correct type and model of pump. This is directly related to whether the pump can meet the system design requirements, the reliability and service life of the pump, the purchase cost of the pump and the total cost of life cycle.

Selection Method:

1. Meet the requirements The performance of the selected pump should meet the requirements of the process design.

2. Pump selection is simple, and the pump with simple structure is preferred. Because compared with pumps with complex structures, the former has the advantages of high reliability, easy maintenance, and low total cost in the life cycle. Examples: single- and multi-stage pumps, vane pumps and reciprocating pumps.

3. Preferred centrifugal pump The centrifugal pump has the characteristics of high speed, small size, light weight, simple structure, no pulsation of infusion, stable performance, easy operation and convenient maintenance. Therefore, centrifugal pumps should be used as much as possible except in the following cases:

4. Special requirements The pump installed in the first area or special occasion should adopt explosion-proof motor or other effective measures according to the first regional grade.

Pump selection steps:

1. Confirm the environmental conditions, including ambient temperature, relative humidity, atmospheric pressure, air corrosivity, hazardous area level, dust and waterproof requirements.

2. Confirm the operating conditions refer to the liquid level pressure (absolute) on the suction side of the liquid, the liquid level pressure on the discharge side, intermittent or continuous work, fixed or mobile position, and the convenience of installation and maintenance.

3. Confirm the properties of the medium, including the name of the medium, temperature, density, viscosity, saturated vapor pressure, diameter and content of solid particles, content of gas, corrosiveness, volatility, ignition and explosiveness, and toxicity.

A water pump is a machine that transports liquids, and no matter what type of water pump it is, it is still impossible to leave the liquid in the end. The water pump can only work if there is liquid. So, when we choose to use a water pump, what criteria should we use to choose the right pump for ourselves?

How to choose a water pumpPerformance is one of the key factors in choosing a water pump.

Generally speaking, water pumps can be classified by industry, principle, use, performance, etc. For example, according to the performance classification, there are explosion-proof pumps, wear-resistant pumps, corrosion-resistant pumps, leak-free pumps, sanitary pumps, automatic pumps, and frequency conversion pumps. The pump industry is a very broad industry, mainly due to the diversity of products.

Most manufacturers will design relevant pumps according to their own expertise.

How to choose a water pumpThe material is the key to choosing a water pump.

Years of experience in the industry have taught us that the basic requirements for a successful pump unit are performance and longevity. Performance is all about the pump's parameters: head, flow and efficiency.

Life is the total number of operating hours before one or more parts must be replaced while maintaining the permissible performance. It is mainly a measure of the resistance of a structural material to corrosion, erosion, or a combination of these two under actual operating conditions. Many companies use stainless steel for their own water pump products, which usually refers to iron-based corrosion-resistant alloys with a chromium content of 12 to 30%.

Stainless steel has the effect of corrosion resistance.

How to choose a water pumpModel and specification are the key three in choosing a water pump.

The pump model represents the structural characteristics, working performance and the nature of the medium to be conveyed. Due to the wide variety of water pumps, the specifications are different. Customers should make a professional choice according to the needs of their own enterprises.

Generally speaking, when the enterprise starts the plant design, the relevant designers will take this into account for you, if it is a reorganized enterprise, you can ask the professional engineers of the senior pump old enterprise to carefully select for you.

Answer 1, stainless steel submersible pump head selection The so-called stainless steel submersible pump head refers to the required head, not the water lifting height, which is particularly important for the selection of water pumps. The head of the pump is about twice the height of the water lifted. If the vertical height from a water source to the water source is 20 meters, the required head is about 23 24 meters.

When selecting a water pump, the head on the pump nameplate should be close to the required head, in this case, the pump has the highest efficiency and will be more economical to use. However, it is not necessary to be absolutely equal, as long as the general deviation does not exceed 20%, the pump can work under the condition of more energy saving. 2. What is the head of the nameplate?

Choosing a pump with a head on the nameplate that is far less than the required head will often fail to meet the user's wishes, and even if it can pump water, the amount of water will be pitifully small, and even become a useless "idle pump". Is it better to buy a pump with a higher head? Not really.

If the pump with high head is used for low head, there will be excessive flow, resulting in overload of the motor, if it runs for a long time, the temperature of the motor will rise, and the winding insulation will gradually age, and even burn the motor. When selecting the pump head, it is necessary to be clear about the concept of the total head h of the pump and the net head h1 of the pump and their relationship. Net head h1 (also known as actual head, refer to the nameplate of the pump) refers to the vertical distance between the water inlet surface and the center (or discharge surface) of the water outlet.

3. Choose a stainless steel submersible pump with the right flow rate The flow rate of the stainless steel submersible pump, that is, the water output, should not be selected too much, otherwise, it will increase the cost of purchasing a water pump. Specific problems should be analyzed, such as the user's own draft self-priming pump, the flow rate should be as small as possible; For example, the submersible pump used by the user for irrigation can appropriately choose the one with a larger flow rate.

(1) Selection of water pumps. According to the design flow rate and design head, use the pump type spectrum or pump performance table to select the pump (the flow rate and head must match), and then check according to the configured pipeline system, if the pump is not running in the high-efficiency area, it should be re-selected.

2) The use of water pumps. If the geographical environment permits, the pump should be installed as close to the water source as possible to reduce the length of the suction pipe. The foundation of the water pump installation place should be firm, the water inlet pipeline should be sealed and reliable, there must be special support, and the water inlet pipe equipped with the bottom valve should be installed vertically with the horizontal plane as far as possible, and the angle between the axis and the horizontal plane shall not be less than 45°.

When the water source is a channel, the bottom valve should be more than one meter higher than the bottom of the water, and the net should be added to prevent debris from entering the pump. The base of the machine and pump should be horizontal, and the connection with the foundation should be firm. When the belt of the machine and pump is driven, the tight edge of the belt is below, so that the transmission efficiency is high, and the steering of the impeller of the water pump should be consistent with the direction indicated by the arrow; When the coupling is used, the machine and pump must be coaxial.

3) Inspection of the water pump. The pump shaft should rotate flexibly without impact sound; There is no obvious shaking of the shaft diameter of the pump, and enough calcium-based lubricating oil is added. Mainly check whether the water inlet pipe is damaged, and repair the cracks in time; Check whether each fastening bolt is loose and tighten the loose bolt.

The motor winding and electrical insulation of the submersible pump should meet the requirements before it can be used.

4) Operation of the water pump. During the operation of the water pump, it is necessary to pay attention to check the vacuum gauge and pressure gauge at any time, monitor and record the working condition of the water pump, listen to whether there is any abnormal noise, whether the temperature at the bearing is too high, whether the stuffing box drips too much or too little, and also check whether the pump speed and belt tightness are normal.

5) Shutdown of the water pump. The submersible pump must be buried in the water to work, once exposed to the water surface, it should be immediately powered off and stop running, otherwise there is a risk of burning. When the high-lift pump is stopped, it should be forbidden to interrupt the power suddenly, otherwise it is easy to cause water hammer and damage the pump or pipeline; For the water conveyance system equipped with gate valves, the gate valve should be closed slowly when it is shut down, and then the machine should be stopped; For pumping units powered by diesel engines, they should also be shut down after gradually reducing oil.

When the pump is shut down in winter, the water in the pump should be cleaned to prevent rust or freeze cracking; In the event of a long-term shutdown, the parts should be disassembled, dried, inspected and repaired, then assembled and stored in a dry place.

According to general experience: the depth of the well should be reserved to prevent the accumulation of silt to block the pump body, but also to meet the minimum requirements of the water level in the dry season, (because the submersible pump can not be dry burned) and the pressure loss caused by the length of the pipe and the elbow, in this way, the pump head is about 35 + 25 + 10 = 70 meters. The flow rate generally has a range value that matches the head, that is:

The diameter of the outlet of the pump with a lift of 70 meters is generally DN50 65 80, and the size of the roof water tank and the amount of water used directly determine the outlet flow of the pump. With these two basic parameters, you can choose the pump according to the pump product sample given by the manufacturer.

For novices, it is still difficult to choose the right water pump.

First, look at the traffic.

The requirement of flow rate is to see how much water the user needs to pump, and in the requirements for the size of the flow, you can choose a single suction pump, a double suction pump, or a small flow centrifugal pump.

Second, look at the head.

Head refers to the height at which the pump can lift water, which is an important working performance parameter of the pump. Users can choose single-stage pumps, multi-stage pumps, or high-speed centrifugal pumps for the height of the head.

Third, look at the use environment.

Head refers to the height at which the pump can lift water, which is an important working performance parameter of the pump. Users can choose single-stage pumps, multi-stage pumps, or high-speed centrifugal pumps for the height of the head.

Fourth, look at the conveying medium.

Head refers to the height at which the pump can lift water, which is an important working performance parameter of the pump. Users can choose single-stage pumps, multi-stage pumps, or high-speed centrifugal pumps for the height of the head.

After the selection basis is clear, the user can provide their own needs to the pump sound field manufacturer, so that the manufacturer can choose the centrifugal pump suitable for the user according to the needs and relevant performance parameters provided by the user.

You can see what the pump you need is used for, and then it is best to go to a point of sale approved by the agricultural machinery department, and be sure to identify the manufacturer. It is recommended to give priority to the purchase of water-filled submersible electric pumps, and to see the brand and product quality certificate. Do not buy "three nos" (that is, no manufacturer, no production date, no production license) products, otherwise there is a problem, and the user will be helpless.

As a user, due to the limitations of professional knowledge, it is difficult to decide, the best way is to consult the pump experts, but also may wish to consult some old pump users, especially those who are similar to their own use conditions, to buy these users trusted, reliable quality and more mature products, it is a wise choice.

If you choose a water stick, you must first look at its water output rate, and your wife should look at its sturdy heart.

For novices, it is still difficult to choose the right water pump.

1. If there is any small fault of the pump, remember not to let it work. If the packing of the pump shaft should be added in time after wear, if the pump continues to be used, it will leak. The direct effect of this is increased energy consumption of the motor, which in turn can damage the impeller.

2. If there is a strong vibration in the process of using the pump, you must stop and check what the cause is, otherwise it will also cause damage to the pump.

3. When the bottom valve of the pump leaks, some people will fill the inlet pipe of the pump with dry soil and flush the bottom valve with water, which is really not advisable. Because when the dry soil is put into the water inlet pipe and the pump starts to work, the dry soil will enter the pump, which will damage the impeller and bearings of the water pump, which will shorten the service life of the water pump. When the foot valve leaks, it must be repaired, and if it is serious, it needs to be replaced with a new one.

4. After the water pump is used, you must pay attention to maintenance, for example, when the water pump is used up, the water in the pump should be cleaned, and it is best to remove the water pipe and then rinse it with clean water.

5. The tape on the water pump should also be removed, and then rinsed with water and dried in a bright place, do not put the tape in a dark and damp place. The tape of the water pump must not be stained with oil, and do not apply some sticky things on the tape.

6. Carefully check whether there are cracks on the impeller, whether the impeller is fixed on the bearing or whether it is loose, if there are cracks and looseness, it should be repaired in time, and if there is soil on the impeller of the water pump, it should also be cleaned up.

What kind of pump to choose, you need to choose according to the specific use and conditions, the following is a list of several factors to choose a pump:

1.Pumps: You can choose different types of pumps, such as self-priming pumps for pond circulation, centrifugal pumps for water treatment, etc.

2.Flow and head of the pump: The corresponding flow and head pump needs to be selected according to the specific requirements to ensure that it can meet the work demand.

3.The power and efficiency of the pump: the difference in power and efficiency will affect the service life and energy consumption of the pump.

4.Noise and maintenance of water pumps: The noise of water pumps used indoors needs to be considered, and the maintenance and maintenance of water pumps are also issues that need to be considered.

In short, choosing the right pump needs to consider a variety of factors, and you need to determine your own use and needs before choosing Changzhu, so as to make the most correct choice.