A slurry pump is a solid-liquid mixed slurry conveying equipment often used to transport all kinds of highly abrasive slurry (mining iron, copper, gold, silver, nickel, and all other ores and minerals slurry), in the operation of the slurry pump of each overflow parts are subject to the slurry abrasion test. Therefore, wear resistance and corrosion resistance are necessary for a high-quality slurry pump.
The abrasion of the slurry pump is related to the size of the solid particles in the slurry and the pH value of the slurry. The use of different wear-resistant materials according to the properties of the slurry is the necessary technical support for the slurry pump factory
In order for the slurry pump to meet the working conditions and use safely, it becomes very important to choose a slurry pump supplier when purchasing a slurry pump. How to choose a suitable slurry pump manufacturer?
01 Good communication skills because timely and effective communication is the cornerstone of cooperation. Only after understanding the slurry pump use conditions and media-related information, manufacturers can provide a reasonable slurry pump selection design
02 The best supplier is a manufacturer with several years of experience in slurry pump production, from casting, heat treatment, machining, assembly, testing to painting and packaging the entire process of slurry pump parts
03 Slurry pump models are complete, we can provide different forms of slurry pumps, such as horizontal slurry pump, vertical slurry pump, submersible slurry pump
04 There are enough pump spare parts in stock, which have been dispatched by customers at any time
05 Experience in exporting industrial slurry pumps to many countries, understanding the whole export and transportation process, familiar with the buyer's market, different countries with different voltage
06 Reasonable prices can be offered
Chinese manufacturers' costs have been rising in recent years, mainly because this
A. labor costs are rising.
B. Material costs are rising.
C. appreciation of the RMB.
D. stricter environmental policies and production restrictions
All factories are affected by these cost increases, and if slurry pump manufacturers are offering prices well below average, special attention should be paid to whether the factory is cutting back on something that really affects quality, or if it is not the true price.
07 Factories with in-depth cooperation provide supporting equipment for slurry pumps, such as pipe fittings, valves, mining machinery, etc., to achieve one-stop service and save customer procurement costs
The future of business is no longer a competition between companies, but competition in the supply chain. Strong suppliers are your recipe for beating the competition.
An Pump Machinery is a professional slurry pump manufacturer with 30 years of experience, for more information, please email to email@example.com
Centrifugal water pump idling usually refers to the situation where there is no water or more air enters the pump casing when the pump is running
When the surface of the stainless steel centrifugal pump brown rust spots (points), people are surprised: think "stainless steel is not rust, rust is not stainless steel, maybe a problem with the quality of steel". In fact, this is a one-sided misconception of the lack of understanding of the stainless steel material. The actual work of stainless steel in certain conditions is also rusted
Stainless steel has the ability to resist atmospheric oxidation - that is, stainless, but also has the ability to resist corrosion in media containing acids, alkalis, and salts - that is corrosion resistance. But the size of its corrosion resistance is with its steel itself chemical composition, use conditions, and environmental media type and change. Such as ss304, in a dry and clean atmosphere, there is absolutely excellent corrosion resistance, but it will be moved to the seaside area, in the sea spray containing a large amount of salt, which will soon rust; and ss316 is a good performance. Therefore, not any kind of stainless steel, in any environment can be resistant to corrosion, not rust.
Stainless steel material rust phenomenon, there may be several reasons.
The presence of chloride ions in the use environment
Chlorine ions are widely present, such as salt / sweat / seawater / sea breeze / soil, etc.. Stainless steel in the presence of chloride ions in the environment, corrosion quickly, even more than ordinary low carbon steel. So there are requirements for the use environment of stainless steel, and it needs to be wiped frequently to remove dust and keep it clean and dry
No solid solution treatment
Alloying elements are not dissolved into the matrix, resulting in low alloy content of the matrix organization, poor corrosion resistance
Inherent intergranular corrosion
Used in applications where welding is required, the lower carbon content minimizes the precipitation of carbide in the heat-affected zone close to the weld, which can lead to intergranular corrosion (weld erosion) of stainless steel in certain environments. Because it will damage the surface of stainless steel and the attachment of iron powder and the formation of the cause of rust. For example, stainless steel centrifugal pump outlet flange and pipeline welding
Stainless steel is formed on its surface by a layer of very thin and strong and fine stable chromium-rich oxide film (protective film), to prevent the continued penetration of oxygen atoms, continued oxidation, and to obtain the ability to resist rust and corrosion. Once there is some reason, this film is continuously destroyed, oxygen atoms in the air or liquid will continuously infiltrate or iron atoms in the metal will continuously precipitate out, forming loose iron oxide, and the metal surface will be subject to continuous rusting.
There are many forms of damage to this surface film, and the following are mostly seen in daily work.
1. Stainless steel surface stored with other metal elements containing dust or foreign metal particles of adhesion, in the humid air, adhesion and stainless steel between the condensate, the two connections into a microcell, triggered an electrochemical reaction, the protective film is damaged, called electrochemical corrosion.
2. Stainless steel surface adhesion of organic juice, in the presence of water and oxygen, constitutes an organic acid, a long time then the organic acid corrosion of the metal surface.
3. Stainless steel surface adhesion containing acid, alkali, salt substances cause local corrosion
4. In the polluted air (such as containing a large number of sulfides, carbon dioxide, nitrogen oxide atmosphere), condensation, the formation of sulfuric acid, nitric acid, acetic acid liquid point, causing chemical corrosion
All of the above can cause the destruction of the protective film on the surface of stainless steel triggering rust and corrosion. Therefore, to ensure that the metal surface is permanently bright and free from rust and corrosion, we recommend that
1. The stainless steel surface must be cleaned and scrubbed frequently to remove adherents and eliminate external factors that cause rust and corrosion
2. According to the centrifugal pump use environment and media to choose the appropriate grade of stainless steel material, such as seaside areas to use 316 stainless steel, 316 material can resist seawater corrosion
3. Some stainless steel centrifugal pumps on the market cannot meet the chemical composition of the corresponding national standards and fail to meet the stainless steel material requirements, thus also causing rust, which requires users to carefully select a reputable stainless steel centrifugal pump manufacturer.
Our client feedback for ss316 material seawater high-pressure multistage pump after running 3 years
The centrifugal pump (except the self-priming pump) must be filled with water before starting, otherwise, the pump will not be able to lift water. The centrifugal pump does not produce water after starting, which is often caused by the fact that the pump is not filled with water before the pump is started, and the air in the pump is not expelled.
There are two main methods of filling water before starting:
One is to use the assembled bottom valve to fill the water. The bottom valve is a one-way valve and is installed at the inlet of the water inlet pipe. The disadvantage of this method is that the head loss of the bottom valve is large, which affects the installation efficiency of the pump;
The other is water filling without the bottom valve. The biggest advantage of this method is energy saving.
Here are some water filling methods for centrifugal pumps for users to choose when running the pump.
self-priming water filling
For the semi-submerged pump house (the pump station where the water inlet pipe and the pump top are both below the water level of the water inlet pool), the water can be introduced into the pump by itself without manual irrigation. The disadvantage of this pumping station is that the water absorption capacity of the pump is not fully utilized, and the installation elevation of the pump is reduced, which not only increases the amount of foundation excavation but also makes the operation and management more inconvenient; but the advantages are also obvious, that is, it is easy to realize the pumping station. Automatic and time-sensitive.
Manual water filling
For small pumping stations with an inlet pipe diameter less than 300mm, the inlet of the inlet pipe is usually equipped with a bottom valve, which is generally used to fill the water manually, i.e. from the special water filling vent at the upper part of the pump shell by the water filling funnel, and also from the outlet of the pump (pumping stations with shorter outlet pipe) to fill the pump with water.
For small pumping stations without the bottom valve, check valve, and short pipeline, you can also use the method of starting while filling water from the outlet to the pump, so as to gradually bring out the air in the pump and pipeline, generally after a few minutes of continuous water filling, the pump can work normally pumping water
Vacuum tank filling
For small pumping stations without the bottom valve, the vacuum water tank filling method can be used. The vacuum water tank is a closed water tank welded with iron sheets, and its volume is at least 3 times the volume of the water inlet pipe. The installation position of the water tank should be as close to the water pump as possible, and the bottom height of the water tank should also be slightly lower than the axis of the water pump. The height of the vacuum tank is generally 2 times the diameter of the tank.
Before starting the pump, fill the tank with water to seal it. After the water pump is started, the water pump enters the water from the vacuum tank. Due to the drop of the water level in the water tank, a certain vacuum is formed in the water tank. The pump starts to run normally.
Jet pump water filling
When the diesel engine is used to drive the water pump to pump water, the exhaust gas discharged by the diesel engine can be used to pass into the jet connected to the top of the water pump to pump air and fill the water, thereby removing the bottom valve of the water pump. When the water pump is started, the valve cover connected to the handle is closed, the exhaust gas is ejected from the ejector, and the air in the pump is sucked out through the connecting pipe. After filling the water, open the valve cover and close the control valve. The advantages of this water filling method are that the power machine is fully utilized, and the efficiency of the pumping station is improved.
Self-suspension water filling
The self-suspension water filling method is realized by the principle of "water-gas replacement" by using the bulk density difference between water and gas. This method can remove the bottom valve of the water pump. First of all, design a ventilation tank with an appropriate amount of containers. The ventilation tank is generally made of plastic or can be a thin iron piece, and the cost is only half of the bottom valve. Then, place the ventilation tank at the water inlet of the water pump to form a connection with the water pump and pipeline. At the same time, a ventilation control valve is installed on the ventilation channel between the ventilation tank and the water pump. When filling with water, fill the ventilation tank with water in advance, then seal it with a lid, and then open the ventilation valve. After the ventilation is completed, close the ventilation valve, and part of the diversion water will be suspended in the water inlet pipe. Repeat this method several times, the air will be completely exhausted, and the water inlet pipe will be filled with water. At this point, the water pump can be started for pumping. Before shutting down, as long as the gate valve is closed first and then shut down, the water diversion will not sit back. The next time you startup, you don't need to water it again. The advantages of this water filling method are that the price of the ventilation tank is lower, the manufacture is easy, the labor intensity is low, and energy is saved
Vacuum pump water filling
For large and medium-sized pumping stations with a water inlet pipe diameter greater than 300mm, or pumping stations with high automation requirements, a vacuum pumping device is a commonly used water-filling equipment. It is assembled by the vacuum pump and other equipment. Most of the vacuum pumps often used in irrigation and drainage stations are water ring vacuum pumps.
The water ring vacuum pump has an eccentric tooth-shaped impeller installed in the cylindrical pump casing. When the pump casing is filled with circulating water, the impeller rotates and under the action of centrifugal force, the circulating water in the pump casing is thrown around the impeller, forming a rotating water ring on the inner wall of the pump casing. Because the impeller is installed eccentrically in the pump casing, the space formed between the water ring and the tooth-shaped vane is different in size. When the impeller rotates clockwise, the space between the two vanes in the right half of the impeller increases gradually, and under the closed condition, as the volume of air increases, the pressure decreases, and a vacuum is formed. Finally, the air is discharged from the vacuum pump through the crescent-shaped exhaust port on the left side of the pump casing and enters the water-gas separation tank, so that the circulating water is separated and then reused. The impeller keeps rotating, the vacuum pump keeps sucking and exhausting, and finally, the pump is filled with water.
Manual pump filling method
As a kind of reciprocating positive displacement pump, it is convenient and economical to fill the centrifugal pump with water. The most common usage is: to install the manual pump on the suction hole of the centrifugal pump or on the water inlet pipeline near the water pump and carry out air suction and water diversion, making it a tool for filling water when the centrifugal pump is turned on, thus saving the need for the water inlet pipeline of the pump. The bottom valve reduces the energy loss and improves the efficiency of the pump unit
Horizontal multistage centrifugal pump installation will involve the installation of the pump head, motor and piping, the process is very complex, if the installation of which link is not in place, may lead to horizontal multistage centrifugal pump unit in later operation can not fully play the energy efficiency, and in serious cases even can not work properly. Today, the technical team of An Pump Machinery to share the horizontal multistage centrifugal pump inlet installation considerations for user reference
Before installing the coupling or belt, check that the steering of the drive is correct and look at the slurry pump for clockwise rotation It is strictly prohibited reverse operation! Otherwise, there will be great damage to people and equipment.
The sludge pump must not be operated for a long time at low or no flow. Otherwise, it will cause the pump unit vibration or even pumping liquid Vaporization, cause equipment damage
The pump is rotating equipment, before installing and maintaining the pump unit, must cut off the power. Otherwise may cause personal injury.
When the pump unit operates, it is forbidden to enter or remove the protective cover, otherwise, it will cause personal injury.
Bearing component assembly
Preheat the inner ring of the bearing during assembly, the temperature is not allowed over 1200C, The bearing inner ring must be fastened to the shaft shoulder or butter retaining ring
For A, B, C, D, E, F, G type bearing components, using a single row of tapered roller bearings, Assembly should be adjusted at the end of the bearing pad to ensure that the axial clearance, axial clearance should be consistent with the following table:
For R, S, ST, T, TU, U bearing components, double row tapered roller bearings are used in the pump end. As the bearing itself has ensured the axial clearance, it is not necessary to adjust the axial clearance.
When assembling the bearing, pay attention to adding the appropriate amount of bearing grease, Bearing end cover is sealed with a piston ring and a labyrinth. When installing the piston ring, note that the gap is diametrically opposed to the arrangement.
The bearing grease is recommended lithium grease 2 # or 3 #. The amount of grease added during assembly can refer to the following table:
|B||C||D||E||F||G||R, RS||S, ST||T, TU|
|Drive end bearing||30||50||100||200||500||1150||200||500||1150|
|Pump end bearing||30||50||100||200||500||1150||400||1000||2300|
Install pump frame plate and cover plate: When tightening the frame plate bolts, tighten the Angle evenly to avoid unevenly damaging the fame plate and cover plate.
Before starting, check the entire unit as follows
The slurry pump should be placed on a solid foundation to withstand the full weight of the sludge pump to remove vibration, tighten all the anchor bolts
The inlet and outlet pipes should have their own brackets. The pipe weight can not be imposed on the pump and the pump and pipe can not be installed when they are not on the same line. There is a gasket on the pump flange when tightening the coupling bolts, should pay attention to making the volute liner higher than the pump flange, at the same time can not over tighten, to avoid damage to the gasket.
Use hands to turn the shaft in the direction of the rotation of the pump. The shaft should be able to drive the impeller and there should be no friction, otherwise, the gap between the impeller and frame plate liner and the gap between the impeller and the throat bush should be adjusted
Check the direction of rotation of the electric motor. Make sure the pump turn in the direction as labeled on the frame plate. Note that the pump must not turn in the reverse direction. Otherwise, the impeller may be screwed off the shaft and damage the pump.
In the direct drive, the shaft of the pump should be exactly co-centric with the shaft of the electric motor. For V-belt drive, the pump shaft and the motor shaft should be parallel. Adjust the position of the groove such that it is perpendicular to be a belt, so as to avoid violent vibration and wear and tear
At the suction pipe, a short removable pipe should be equipped, the length of which should be such that the cover plate and other wearing parts could be repaired easily by removing this pipe.
Check the shaft sealing systems. If the expeller ring has a grease cup, lubricants should be added via the grease cup.
Before starting the pump, first, open the shaft seal water to prevent the packing or mechanical seal from being burned due to heat generation. During the operation, the pressure and flow of the shaft seal water should be regularly checked to adjust the packing gland or replace the packing. To ensure that there is always a small amount of clean water through the shaft
Fully open the inlet valve;
Fill water into a pump (when the pump is in the flood suction no need to fill with water );
Adjust the outlet valve opening to 1/4;
Start the pump. when the speed is normal, can slowly open the outlet valve until completely open or meet the requirements of working conditions.
Check the bearing assembly regularly. If the bearing gets overheated when the operation is started, the pump should be switched off to let the bearing cool down, then switch on the pump again. When the bearing still gets severely overheated and the temperature keeps rising, the bearing assembly should be stripped and carefully examined to find out the reason. Usually, overheating is caused by excessive lubricant or impure lubricant. The lubrication should be a clean and appropriate amount. The grease should be added regularly.
The efficiency of the pump decrease as the gap between the impeller and throat bush increases. Thus the impeller should be moved forward regularly to ensure the gap is kept at an appropriate size. When the parts are worn such that the system requirement can not be met, the wearing parts should be replaced.
Before shutting down the pump, if possible, the pump should be allowed to transport clean water for a while so as to clean the slurry inside the pump
Then close the inlet and outlet valves
The packing seal water must be open throughout the continuous operation cycle, which is to be activated during start-up, operation, parking, and re-operation. If it is a mechanical seal after the pump is stopped, it is necessary to continue to maintain the supply of seal water, and the mechanical seal can be stopped after it has cooled down
To make the pump safe operation, we must pay attention to the daily maintenance, maintenance should pay attention to several aspects
For a packed gland seal pump the water pressure and water volume of flush seal water should be checked regularly. Make sure that there is always some clean water passing around the shaft. Adjust the gland assembly regularly. check the stuffing regularly and replace the stuffing if necessary. The pressure and flow rate of the sealing water should meet the standards stated. The expeller seal pump with grease cups should be filled with grease regularly to lubricate the internal packing
In order to ensure the efficient operation of the pump, the gap between the throat bush and the impeller should be adjusted regularly. The distance between the impeller and the throat bush should be kept at 0.5-1 mm in the metal liner pump. The gap between the impeller and liners should be kept the same in the rubber liner pump. To adjust the gap between liners and impeller, shut down the pump first. Lose the bolt which presses the bearing assembly tight. Tighten the nut on the adjusting screw to move the bearing assembly forward. At the same time, use hands to turn the shaft in the direction of the pump until the impeller and throat bush are next to each other. For metal liner pumps, loose the just tightened nuts half a circle and tighten backward. The gap between the impeller and throat bush is 0.5-1 mm. For rubber liner pumps, tighten the nut on the adjusting screw to move the bearing assembly forward, so that the impeller just touches the cover plate liner. Then move the bearing assembly backward until the impeller touches the frame plate liner insert. Measure the distance that the bearing assembly has been moved. Take half of this distance as the gap between impeller and cover plate liner and impeller and frame plate liner. Adjust the position of bearing assembly using an adjusting Screw to make sure that the gap between impeller and front and back liners are of the appropriate amount. After adjustment check, if the impeller operates correctly before starting the operation again.
The service life of the pump will be longer if the bearing assembly is correctly assembled. the lubricant is of the right amount and the pump is regularly maintained.
Maintenance staff should check the bearing assembly and the amount of lubricant regularly. Usually, the pump should be maintained at least every 2 months. When the pump is in operation, lubricant should be added regularly. The frequency and amount of which depends on the speed of revolution, type of bearing, continuous work time, the number of times that the pump is shut down, ambient, temperature, etc.
The Pump that has not been used for a long time should be turned a quarter of a revolution every week to make sure that every part of the bearing evenly withstands the static load and external vibration.
The Frame Plate and Frame are used for a long time and the tensile strength is reduced. Check and replace them in time
The quality of centrifugal pump installation directly affects the efficiency of pump use, service life, economic efficiency, and the safety of the person and the unit, and must be given full attention.
In the case of ensuring safety, install the pump as close to the water source and steep slope as possible to shorten the length of the inlet and outlet pipes and reduce unnecessary bends and joints, so as to reduce the possibility of air leakage and head loss.
The vertical height of the pump from the river surface or the water surface of the inlet pool must be less than the maximum allowable suction head of the pump at the driest water level and not flood the unit in the flood season
The foundation where the pump is installed should be solid and dry so that the pump will not sink and the motor will be damp due to vibration during operation.
The location where the pump is installed should have sufficient workspace for disassembly and overhaul
Before installing the coupling or belt, check that the steering of the drive is correct and look at the pump for clockwise rotation It is strictly prohibited reverse operation! Otherwise, there will be great damage to people and equipment.
When the water pump is directly connected to the motor or diesel engine, it must use the integral base and pay attention to the flat base
For units directly connected by coupling, the pump and drive shaft must be concentric to prevent damage to the machine parts due to vibration.
When using a belt-drive, the tight side of the belt should be at the bottom and the loose side should be at the top.
The inlet pipe support must be firm and cannot fall on the pump, and the joints should be strictly sealed and should not leak.
The elbow cannot be directly connected with the pump inlet, and a straight pipe with a length of about 3 times the diameter must be installed, otherwise, the water flow at the water inlet of the pump will be disturbed and the efficiency of the pump will be affected
The inlet pipe with a bottom valve should be installed vertically if it must be installed obliquely due to terrain limitation, the angle with the water surface should be more than 45 degrees, and the direction of the valve shaft pin should be in the horizontal direction, so that the bottom valve can not be closed or closed tightly, affecting the work of the pump.
Before starting the pump, check whether the bolts at each fastening are loose, whether there are abnormal noises, whether the lubrication parts have sufficient oil, etc., so as to exclude possible problems as early as possible to avoid losses.
Turn the shaft by hand in the direction of rotation of the pump, Should be able to drive the impeller shaft rotation， there should be no friction
Before starting the pump, the pump body and inlet pipe filled with liquid, close the gate valve and outlet pressure gauge, after the pump is running normally, slowly open the outlet pipe valve and pressure gauge.
Regularly check the bearing assembly operation. If the bearing heats up at the beginning of the operation, the pump can be stopped and the bearing can be cooled and then run again. If the bearing is still serious heat, the temperature continues to rise, the maximum temperature must not exceed 80 ℃. The bearing assembly must be dismantled to check the cause. General bearing heat is caused by excess oil or impurities in the oil. The amount of bearing oil is based on the oil level in the middle of the oil window. After the oil level is lower than the centerline of the oil window, add oil immediately.
Before stopping the pump shutoff gate valves, the pressure gauge, and then stop the motor.
When the pump is used during the winter season, it is necessary to drain the medium in the pump after stopping it to prevent frost cracking.