Diffusion pump: characteristics, principle of operation

Table of contents:

Diffusion pump: characteristics, principle of operation
Diffusion pump: characteristics, principle of operation

The traditional diffusion pump belongs to a large category of vacuum units that are used to create certain working conditions. The key feature of such products is that they do not have any limitation in providing pressure. Today, this technology is considered not fully understood, since experts have not yet had time to conduct a sufficient amount of research. But many experts say that the principle of operation of diffusion pumps allows you to achieve the highest performance.

Diffusion pump at home


When working with various units, the quality of the final result often depends on the knowledge of the basic principles of operation of the diffusion pump. Depending on the basic element that is installed in the vacuum unit, even with a slight change in pressure in the pipes, both mercury vapor jets and oil can be used. The final efficiency of each product differs in individual indicators.

The principle of operation of the diffusion pump is based on the capture and subsequent transportation of gas particles, whichpenetrate into the inner compartment through small holes leading to the nozzle. Next to the name, manufacturers often indicate displacement. For example, the H400 diffusion pump model says that the product needs four hundred liters of water to work.

Pumping station


Irrespective of the displacement of the coolant used, the diffusion vacuum pump differs in the principle of operation, which is the same for absolutely all models:

  1. The installed steam vent consists of heavy duty aluminum four-stage nozzles, which are equipped with small clearances for nuts and wear washers.
  2. To reduce the loss of working fluid in the outlet pipe, manufacturers have provided for the presence of a universal oil deflector.
  3. Tube heaters made of copper are subject to stable heating, as they are partially in the working fluid. The heat generated during operation is transferred to the charged substance.
  4. In order to qualitatively eliminate the process of back-flow of displaced gas particles, an oil deflector is placed above the uppermost nozzle. The unit is cooled by water.

Classic steam oil diffusion pumps can be used in combination with any filling media. It can be not only vapors, but also gases that do not act destructively on the unit itself. To use the product at full capacity, it must be equipped with a backing pump, which is installed exclusively at the outlet of the pipes. Quality oil fordiffusion pumps ensures the smooth operation of the entire system.

Pump oil

Working principle

The NVDM diffusion pump in its specifics is more like a classic ejector. A similar situation is with the principle of operation, which consists in a kind of diffusion of the pumping gas (outwardly, it looks more like a steam jet). When the condensation process comes to a logical conclusion, the gas gradually leaves the unit, which does not affect the level of vacuum in the internal compartment at all. Timely pumping is carried out by activating the installed pump. The use of a durable and reliable nozzle allows you to increase the performance level by several times, increasing the efficiency of the unit.

advanced model

Terms of Use

Today, the universal principle of the diffusion pump is actively used in various industries. The correct approach to the operation of the unit can significantly improve performance. Wide functionality is highly appreciated by experienced professionals. The equipment is most often used in the following industries:

  1. Metallurgy.
  2. Medicine.
  3. Serial production.
  4. Oil industry.

The leadership of all these industries is interested in buying steam jet diffusion pumps. If all the functionality of the unit is applied as intended, then the productivity of the entire enterprise can be improved. Anyone can buy a unit.You just need to understand that there are a number of specific criteria that must be taken into account by both specialists and beginners. The main thing is that all installed products are compatible with each other.

Diffusion vacuum pump

Demanded manufacturers

Experts identify several brands whose products are most popular among modern consumers. The most popular are:

  1. Erstevak.
  2. "Intech Analytics".
  3. MSHTechno.

Each of these companies professionally produces a wide range of products. The total cost of a diffusion pump varies depending on what performance characteristics the unit is endowed with. More expensive models are designed to create a deep vacuum.

Modern model

Universal products NVDM

You can buy an oil diffusion pump in any specialized store that sells expensive and high-quality equipment, featuring excellent technical parameters and a well-coordinated principle of operation. If a beginner cannot make the right choice, then it is best to consult a professional. To solve standard problems, you can purchase the diffusion pump H 250, which is suitable for both domestic needs and for installation in organizations.

The multifunctional device will be a great helper in any modern production, as it is distinguished not only by good power, but alsoa high degree of performance. With a purchase, you should never rush, as you can buy a low-quality fake. More advanced pumps have found their application in the chemical, oil, and food industries. Those enterprises that are professionally involved in the sale of such units must provide customers with a warranty card. Only in this case, you can be completely sure that the purchased pump will not fail in the first week of active operation.


By studying the detailed documentation of the diffusion pump, even a beginner can understand that the principle of the unit is quite simple. Positive characteristics are achieved due to the fact that the product has a clear sequence of actions:

  1. Heated steam in the tank gradually moves through the main pipe.
  2. At the point of connection with a small capillary tube, it interacts with the main working fluid, which boasts low elasticity.
  3. Gas particles are captured, after which the steam transfers them to an equipped trap, consisting of a cooling oil deflector. Due to this, condensation occurs.
  4. Installed foreline pump pumps out all excess.

Insufficient pumping rate most often indicates a lack of water supply. The final efficiency of the gas outlet, which is provided by a vapor-jet diffusion pump, largely depends on the shape of the installed nozzles. Flat products improve the quality and speed of pumping.

Powerful photo station


Modern manufacturers produce a huge number of different diffusion pumps, which differ from each other in performance and price. All of them are unique in their own way. But there are a few models that are in high demand in large production areas. The H 100 unit is distinguished by its low power and minimum price. Such products are common in the household industry, where there is enough low performance.

The model H 250 belongs to the middle class, which can be periodically used in large enterprises. The main thing is to choose the most suitable operating conditions. The diffusion pump H 400 has optimal performance. Large factories use such units in series production, where they can show their full potential.


The operation of the diffusion pump can be compared to a household vacuum cleaner, which is actively used by builders for whitewashing rooms. Small gas molecules are eliminated by the strong flow created by the working medium. The great popularity of such products is associated with numerous advantages:

  1. The pumping speed is at the highest level.
  2. You can use the unit even for domestic purposes, since the product does not need to be additionally cooled with liquid nitrogen.
  3. Long service life.
  4. Affordable price.
  5. Mutual overlapping of surfaces, which ensures high-quality pumping.
  6. Stablehigh performance designs.

If you need to create a certain vacuum at the production site and maintain it continuously, then diffusion steam-oil pumps are ideal for these purposes, which can be safely used to pump out air, various vapors and gases. If the consumer takes into account all technological requirements and environmental features, then the production process will be carried out without any disturbances and with high performance.

Popular topic