In the process of industrial production, it is often required to meet the accurate transportation process of small flow, low viscosity, high pressure difference and non pulsation transportation at the same time. Users usually consider using conventional multistage centrifugal pump, diaphragm metering pump, ordinary oil pump or some relatively cheap low end gear pumps. However, there are always many defects in the process. For example, in the coating industry, optical media additives and micro spray require the medium to be transported with low flow rate and low viscosity, and no pulsating precision transportation is required. However, conventional pumps are difficult to achieve. So what kind of pumps should be used to meet the above requirements? The answer is to choose an external meshing micro gear pump with good performance. This pump can handle the above working conditions well by optimizing material, internal clearance control and modular design. Based on this, this article will give you a comprehensive understanding of the solution of jonsn brand micro gear pump in dealing with small flow, low viscosity, high pressure difference and no pulsation transmission.

General customers mainly have the following problems:

1. The centrifugal pump has large flow, low pressure and instability, and is inefficient when transporting viscous media. It is suitable for low viscosity media, large flow transportation and no accuracy requirements;

2. Peristaltic pump / hose pump can transport small flow quantitative addition conditions, but the output pressure is low, the pulsation is large and the continuity is poor when transporting liquid;

3. Although the diaphragm pump / metering pump measures accurately, it also has large pulsation and poor liquid continuity.

4. Ordinary gear oil pump can handle some media with high lubricity and viscosity, but transporting materials with low viscosity and poor lubricity will make the gear wear quickly and shorten the service life.

Through the above analysis, the conventional pump is difficult to meet the requirements of small flow, low viscosity, high pressure difference, no pulsation and accurate conveying at the same time. There are many process defects in the conveying process. Next, focus on the micro gear pump.

Working principle and design points of precision micro gear pump:

The micro gear pump adopts the working principle of the traditional external meshing gear pump (see the figure above). The liquid enters the suction end of the pump and is sucked by the non meshing inter tooth cavity. The outer diameter and both sides of the gear are closely matched with the shell. With the rotation of the teeth along the shell, the liquid between the teeth is brought to the outlet end, and the liquid is continuously transported out without pulse again and again. Gear pump, also known as positive displacement pump, has the characteristics of stable flow, high and stable pressure. Theoretically, the rated flow of positive displacement pump has nothing to do with the pressure, but the internal leakage problem is inherent to all positive displacement pumps, especially when transporting low viscosity media, which will directly affect the flow and pressure. In order to meet the required flow when reaching the high pressure difference, The gear pump must overcome the problem of internal leakage to the greatest extent. There are four ways of internal leakage (see the figure below). In order to maximize the performance of the pump, theoretically, the matching clearance of these components must be as small as possible to control internal leakage. However, just reducing the clearance is not as simple as it says. It is also necessary to design different clearances under different working conditions, such as temperature, viscosity and material characteristics. In the gear pump, a certain amount of internal leakage is good for the pump. For example, it can be used for internal bearing lubrication, reduce the friction temperature of sliding bearing and improve the service life of the pump. Clearance control is a contradictory process. If the clearance is large, the internal leakage will be large, and if the clearance is small, the bearing lubrication and cooling will not be good. Therefore, the clearance control needs a lot of application data and experience to support.

The selection of material is a very important part in the selection of micro gear pump. Micro gear pump is often used to transport various organic solvents and corrosive media. In addition to matching the selection of pump body, gear shaft, sliding bearing and seal with liquid, the dynamic stress analysis of gear shaft should also be considered. The gear is tested by contact stress and fatigue strength in the process of rapid meshing, And the application occasions are mostly used under the condition of low viscosity and no lubrication, which puts forward higher requirements for the gear shaft.

At present, the mainstream methods of micro gear shaft in the market are polyphenylene sulfide PPS injection molded gear embedded stainless steel shaft, peek injection molded gear embedded stainless steel shaft and peek modified injection molded gear embedded ceramic shaft, as shown in the figure.

1. Peek modified material is preferred for gears. Peek is a special engineering plastic with excellent performance. Compared with other special engineering plastics, peek has more significant advantages, such as high temperature resistance, excellent mechanical properties, good self-lubricating property, chemical corrosion resistance, flame retardant, peel resistance, wear resistance and other super strong mechanical properties. Compared with metal materials, peek has good self-lubricating performance, so it can work for a long time without additional lubrication system when transporting low viscosity non lubricating media. Usually, metal gears are mainly used in media with viscosity and certain lubricity, so when transporting low viscosity lubricating media, using ordinary oil pump will have problems and wear will be very serious.

2. Ceramic shafts are preferred. New structural ceramics have the advantages of corrosion resistance, high toughness, high bending strength, high wear resistance and thermal expansion coefficient close to steel. They have been widely used in the fields of aviation and nuclear industry. Under severe working conditions, the pump with stainless steel shaft can not compare with it. The experiment shows that the bearing life of the pump with ceramic shaft is greatly improved, which is 2-3 times that of the stainless steel shaft pump.

Why choose jonsn micro gear pump when dealing with small flow, low viscosity, high pressure difference and no pulsation?

Jonsn micro gear pump is a rising star. It summarizes the design shortcomings and advantages of gear pumps of peers at home and abroad. Through in-depth research on gear pumps of previous generations (or on the market) and long-term use visits to customers, we deeply optimize and improve the pump, carry out lean management in design, development and production, and adopt modified peek materials, The selection of imported ceramic gear components has made a qualitative leap in the service life of our gear pump. Under the same working conditions, the service life of our gear pump is longer.

In designing products, we pay special attention to the following points:

-Standardized and modular structure

-Miniaturization of internal and external dimensions

-Accuracy and interchangeability

-High reliability

-Low power consumption

Professional selection before sales

Tens of thousands of micro gear pumps have accumulated a large number of experimental data and professional type selection evaluation to formulate solutions for you and reduce risks.

With the perfect internal structure optimization and high-performance materials as the support, the next step is to apply the pump to suitable occasions with low viscosity, small flow, high pressure difference and no pulsation requirements: it is commonly used in fine chemical industry, polymer special materials, SCR industrial tail gas treatment system, lithium battery coating, electronic optical film and other industries. The practical applications of several industries are listed below.

Lithium battery coating application:

Description of working conditions:

1. Medium N-methylpyrrolidone has low viscosity and requires accurate flow for real-time transportation,

2. It is required that when the outlet pressure is stable, the pump is not allowed to produce pressure fluctuation during delivery,

By controlling the machining accuracy and clearance, jonsn brand micro gear pump has the ability to deliver low viscosity, small flow, high precision and pulse free delivery. Our pump has been widely used in Ningde era new energy.

Optical film applications:

Working condition description: the addition of additives requires high fluid transmission accuracy, high repeatability, continuous addition without pulsation and small flow, so as to ensure the consistency of product mechanism.

Jonsn brand micro gear pump has been successfully applied to the production of Kangde new optical film.

Application of SCR industrial tail gas treatment system:

Working condition description: when transporting urea solution, the medium has no viscosity, small flow and high pressure, so it is required to obtain good atomization effect.

JONSN brand micro gear pump can work under 10Bar-15Bar pressure for a long time. The accuracy of the conveying flow can be controlled by the speed of the motor. It can also achieve very good spray effect without the gas source. We have worked with several large environmental protection companies in China and have made many successful achievements.

Application of jonsn micro gear pump in nuclear industry and heavy water industry:

As early as 2012, we had a user who mainly produced heavy water. Heavy water is known as gold in water. It is used in the nuclear industry and needs to be extracted from a large amount of water. The production unit is required to operate 24 hours a year, with a transmission water volume of 220l / h and a working pressure of 6bar. Japanese technology was adopted in the early stage of plant construction. All the pumps equipped in the production process are vortex pumps of a Japanese brand, one for operation and one for standby, As the vortex pump is not a positive displacement positive displacement pump, its efficiency is extremely low under such high pressure. All pumps have to operate at full load, and new spare parts must be replaced every two months, which makes the maintenance engineer miserable. Because all spare parts are imported from Japan, the annual cost of spare parts is up to several hundred thousand yuan. Our engineer conducted a field survey after learning about it, We provided them with a professional selection scheme. The selected pump model is mrb170szklf. The motor adopts ABB high-efficiency 370W variable-frequency motor, and the speed is set at 2300rpm. After two years of operation, not only did we not replace spare parts, but the flow was very stable and did not fluctuate. At the same time, the service life of instruments and meters in the rear section of the pipeline was improved. The owner praised our pumps and services, All vortex pumps on the previous units have been replaced one after another, and jonsn micro gear pumps have been adopted for new projects in 2015.

Summary: when you meet the precise conveying process of low viscosity, small flow, high pressure difference and non pulsation conveying at the same time, many types of pumps can not meet it, so please choose the precision micro gear pump.

At present, there are many manufacturers of micro gear pump, but few can optimize gear tooth profile design, adopt high-performance materials, gap calculation and gap control ability and application experience in relevant industries, which are often the embodiment of enterprise soft power and the character of micro gear pump.