Several performance and technical characteristics and application fields of progressive cavity pump

Able to transport high-concentration sludge: The progressive cavity pump has a large volume and can convey high-concentration sludge, which is suitable for sewage treatment sites with high sludge concentration.

Low noise and low vibration: The operation noise of the progressive cavity pump is low, the vibration is small, and it will not cause interference to the surrounding environment and equipment.

Able to convey high-viscosity media: The progressive cavity pump has a large volume and a small internal clearance, which is capable of conveying high-viscosity media, and is suitable for treating high-concentration sludge and high-viscosity sewage.

Energy-efficient: The screw pump has high conveying efficiency, which can save energy and reduce operating costs.

Easy maintenance: The progressive cavity pump has a simple structure and easy maintenance, which can reduce maintenance costs and downtime.

The application fields of progressive cavity pump in sewage treatment mainly include:

Sludge Conveying: The progressive cavity pump is capable of conveying high concentration sludge and is suitable for sewage treatment sites with high sludge concentration.

Sewage lifting: Progressive cavity pumps are capable of conveying high viscosity sewage and are suitable for sewage lifting and conveying.

Sewage treatment: progressive cavity pumps can transport sewage and sludge, and are suitable for various sewage treatment sites, such as municipal sewage treatment plants, industrial wastewater treatment plants, etc.

Sludge dewatering: Progressive cavity pumps are capable of conveying high concentrations of sludge and are suitable for conveying and pressurizing sludge dewatering processes.

1. The speed of the screw pump is selected.

The flow rate of the screw pump is linearly related to the speed, compared with the low speed of the screw pump, although the high speed of the screw pump can increase the flow and head, but the power increases significantly Chinese New Year's Eve, the high speed accelerates the wear between the rotor and the stator, must make the screw pump fail prematurely, and the stator and rotor length of the high speed screw pump is very short, easy to wear, thus shortening the service life of the screw pump. The speed is reduced by the deceleration mechanism or the stepless speed regulation mechanism, so that the speed is connected in a more reasonable range of less than 300 revolutions per minute, and the service life can be extended several times compared with the high-speed operation of the screw pump.

2. Make sure that debris does not enter the pump body.

The solid debris mixed in the wet sludge will cause damage to the rubber stator of the screw pump, so it is very important to ensure that the debris does not enter the cavity of the pump.

Third, the quality of the screw pump.

At the moment, there are many types of screw pumps on the market, relatively speaking, the imported screw pumps are fair in design, exquisite in material, but the price is higher, some of the service is not in place, the price of accessories is high, and the order cycle is long, which may affect the normal operation of production. Most of the domestic production is imitation of imported products, the quality of the products is uneven, in the selection of domestic production products, when considering its cost performance, the selection of low speed, long lead, transmission parts of good material, long rated life of the product.

Fourth, avoid material breakage.

The screw pump is never allowed to run under the scene of breaking the material, once generated, the rubber stator burns out due to dry friction, instantaneously high temperature occurs, therefore, the destruction machine is intact, and the grid is unobstructed is one of the conditions required for the normal operation of the screw pump, for this reason, some screw pumps are also installed on the pump body to stop the assembly, when the material is broken, because the screw pump has the characteristics of self-priming function, the vacuum will occur in the cavity, and the vacuum device will make the screw pump curb the operation.

5. Connect to a constant outlet pressure.

Screw pump is a kind of volumetric reverse rotary pump, when the outlet end is blocked in the future, the pressure will gradually rise, so that it crosses the predetermined pressure value, at this time the electromechanical load increases sharply, the load of the transmission machinery related parts will also exceed the design value, in serious cases, electromechanical burning, transmission parts breakage, in order to avoid the destruction of the screw pump, generally will be installed at the outlet of the screw pump bypass relief valve, in order to keep the outlet pressure, the normal operation of the pump.

Activated carbon filtration, multi-media filtration, membrane filtration (microfiltration, ultrafiltration, reverse osmosis), crystallization evaporation.

Sludge screw pump Chunbu sedan is a special-purpose screw pump, which is mainly used to transport sludge, slurry, sludge and other media with high viscosity and solid particles. The following are the categories and selections of sludge progressive cavity pumps, and the flow control and adjustment methods

Category & Selection:

The categories of sludge progressive cavity pumps are generally classified according to the rotor structure, drive mode, flow regulation mode, etc. The common categories are progressing cavity pumps, twin screw pumps, triple screw pumps, etc. The selection needs to be determined according to the nature of the medium, the conveying distance, the flow rate, the pressure and other parameters.

Flow Control Regulation Method:

There are generally the following methods for flow control and adjustment of sludge screw pump:

1) Manual valve adjustment: The flow rate can be adjusted by manually adjusting the opening of the valve.

2) Inverter control: The flow control is realized by adjusting the speed of the motor through the inverter.

3) Adjust the speed of the screw: The control of the flow rate is realized by adjusting the speed of the screw.

4) Adjust the inlet pressure: Control the flow by adjusting the inlet pressure.

5) Intelligent control system: use sensors and controllers to realize automatic control of flow.

In short, when selecting sludge screw pump, it is necessary to select the type according to the specific application scenario and the characteristics of the conveying medium, and in the process of use, it is necessary to choose the appropriate flow control and adjustment mode to ensure the safe and stable operation of the pump and achieve the best work efficiency.

Performance characteristics of sludge progressive cavity pump:

Sludge progressive cavity pumps, i.e., single progressive cavity pumps, have the common advantages of progressive cavity pumps. It is suitable for conveying media with low viscosity such as water, but also for suspensions containing solid particles or short fibers, as well as for media with very high viscosity.

1. Wide range of pressure and flow. The pressure is about kilogram-force cm2, and the flow rate can reach 18600cm3 minutes;

2. A wide range of types and viscosities of liquids to be transported;

3. Because the inertia force of the rotating parts in the sludge screw pump is low, a high speed can be used;

4. Good inhalation performance and self-priming ability;

5. The flow rate is uniform and continuous, the vibration is small, and the noise is low;

6. Compared with other rotary pumps, it is less sensitive to incoming gases and dirt;

7. The structure is solid, and the installation and maintenance are easy.

Working principle of sludge progressive cavity pump:

The sludge progressive cavity pump is a single-screw conveying pump, and its main working components are the screw (called the rotor) of the eccentric spiral body and the screw bushing (called the stator) with a double-line spiral surface on the inner surface. Its working principle is that when the motor drives the pump shaft to rotate, the screw rotates around its own axis on the one hand, and on the other hand, it rolls along the inner surface of the bushing, thus forming the dense smile sealing chamber of the pump. With the continuous rotation of the screw, the liquid in the sealing chamber is pushed forward by one pitch, and with the continuous rotation of the screw, the liquid is pressed from one sealing chamber to another to touch the sealing chamber, and finally the pump body is extruded.

Screw pump is a new type of machinery for transporting liquids, which has the advantages of simple structure, safe and reliable work, convenient use and maintenance, continuous and uniform liquid, and stable pressure.

A sludge progressive cavity pump is a pump that uses the rotation of the screw to suck and discharge liquids, and it is most suitable for sucking and discharging viscous liquids.

Selection of sludge progressive cavity pumps.

1. Determine the pressure: the rated pressure of the selected sludge screw pump should be slightly higher than the actual maximum pressure required, generally higher than 10 20. Don't choose too high, too much pressure will waste energy, increase the investment and operating costs of the equipment.

2. Determine the flow rate: the selected sludge screw pump flow rate should be equal to or slightly greater than the flow required by the process. The use range of sludge screw pump flow is better in the rated flow range of sludge screw pump 30 100, and the repeatability of sludge screw pump is high at this time.

Considering the economy and practicality, it is recommended that the actual required flow rate of the sludge screw pump should be selected as 70 90 of the rated flow rate of the sludge screw pump.

3. Determine the material of the pump head (hydraulic end): after the specific model and specification of the sludge screw pump are determined, the material of the overflow part is selected according to the attributes of the overflow medium, this step is very important, if the selection is not done properly, it will cause the medium to corrode and damage the overflow parts or the medium leakage and pollution system. In severe cases, it can also cause major accidents.

Sludge screw pump flow control and adjustment methods.

There are three kinds of adjusting the piston or piston stroke, adjusting the pump color, and building the stroke adjustment and pump speed, among which the way of adjusting the stroke is the most widely used. The method is simple and reliable, and can maintain high metering accuracy at small flow rates. There are three ways to adjust the stroke:

1. Manual adjustment when parking: Manually lift the stroke of the sludge screw pump when parking.

2. Manual adjustment during operation: change the axial displacement during the operation of the pump to change the radius of the crank concisely to achieve the purpose of adjusting the stroke length. The commonly used methods include N-shaped crankshaft adjustment, L-shaped crankshaft adjustment and eccentric cam adjustment.

3. Automatic adjustment during operation: there are two common types: pneumatic control and electric control. Pneumatic control is to achieve the purpose of automatically adjusting the stroke by changing the pressure signal of the air source; Electric control is to achieve the purpose of automatically adjusting the stroke by changing the electrical signal.

Control of sludge progressive cavity pump: the precise processing accuracy ensures the output of each pump and realizes the precise measurement of the conveyed medium. At a certain effective plunger area, the volume flow rate of the output fluid of the pump is proportional to the stroke length and reciprocating frequency, i.e., the pump speed. Or messy.

Categories and selection of sludge progressive cavity pumps:

According to the structure and use of the pump, sludge screw pump can be divided into ordinary sludge screw pump, anti-clogging sludge screw pump, rubber lined sludge screw pump, etc.

The ordinary sludge progressive cavity pump is suitable for conveying general sludge or liquids containing a small amount of solid particles, while the anti-clogging sludge progressive cavity pump is suitable for conveying more viscous sludge or liquids containing more solid particles. Rubber-lined sludge progressive cavity pumps are suitable for conveying highly corrosive liquids such as hydrochloric acid, sulfuric acid, etc.

When selecting the model, it is necessary to select the appropriate sludge screw pump model, material and configuration according to the actual use requirements and fluid characteristics of the section core.

Flow control and regulating the flow control of sludge screw pumps

Manual adjustment: The flow rate of the sludge progressive cavity pump can be controlled by manually adjusting the opening of the inlet valve.

Frequency conversion speed regulation: Install a frequency converter to realize the regulation and control of the flow rate by controlling the motor speed of the pump.

Frequency control: Regulate and control the flow rate by controlling the motor frequency of the pump.

PID control: The PID controller is installed to achieve accurate control of the flow rate of the sludge screw pump according to the flow feedback signal.

It is necessary to choose the appropriate flow control and adjustment method according to the actual situation to ensure the normal operation and use effect of the sludge progressive cavity pump.

Because of its variable conveying, strong self-priming ability, reversible, and ability to convey liquids containing solid particles, progressive cavity pumps are widely used in sewage treatment plants to transport water, wet sludge and flocculant liquids. The selection of screw pump should follow the principle of economy, reasonableness and accessibility. If the design and selection are not well considered, it will bring trouble to the future use, management and maintenance, so the selection of a reasonable and reasonable screw pump according to the actual needs of production can not only ensure the smooth progress of production, but also reduce the repair cost.

1. The speed of the screw pump is selected.

The flow rate of the screw pump is linearly related to the speed, relative to the screw pump of low speed, although the screw pump of high speed can increase the flow rate and head, but the power is obviously increased, the high speed accelerates the wear between the rotor and the stator, must make the screw pump fail prematurely, and the stator and rotor length of the high speed screw pump is very short, and it is easy to wear, thus shortening the service life of the screw pump.

The speed is reduced by the deceleration mechanism or the stepless speed regulation mechanism, so that the speed is kept within a reasonable range of less than 300 revolutions per minute, and the service life can be extended several times compared with the high-speed operation of the screw pump.

Second, the quality of the screw pump.

Now there are many types of screw pumps on the market, relatively speaking, the imported screw pumps are reasonably designed and made of excellent materials, but they are high, the service is not in place, the accessories are high, and the order cycle is long, which may affect the normal operation of production.

Most of the domestic production is imitation of imported products, the quality of the products is uneven, in the selection of domestic products, in the consideration of its cost performance, the selection of low speed, long lead, transmission parts of the material is excellent, the rated life of the long products.

3. Ensure that debris does not enter the pump body.

The solid debris mixed in the wet sludge will cause damage to the rubber stator of the screw pump, so it is very important to ensure that the debris does not enter the cavity of the pump.

Fourth, avoid material breakage.

The screw pump is never allowed to run in the case of material breaking, once it happens, the rubber stator is burned out due to dry friction, instantaneously produces high temperature, therefore, the crusher is intact, and the grid is unobstructed is one of the necessary conditions for the normal operation of the screw pump, for this reason, some screw pumps are also installed on the pump body to stop the material stop device, when the material is broken, due to the self-priming function of the screw pump, the cavity will produce vacuum, and the vacuum device will make the screw pump stop running.

5. Maintain a constant outlet pressure.

A progressive cavity pump is a positive displacement rotary pump, and when the outlet end is blocked, the pressure gradually rises to a predetermined pressure value. At this point, the motor load increases dramatically. The load of transmission machinery-related parts will also exceed the design value, and in severe cases, motor burnout and transmission parts will break.

In order to avoid damage to the progressive cavity pump, a bypass relief valve is generally installed at the outlet of the progressive cavity pump to stabilize the outlet pressure and maintain the normal operation of the pump.