pvd coating machine is currently the most widely used vacuum equipment for making vacuum conditions. It is generally composed of three parts: vacuum chamber, vacuum unit and electrical control cabinet. polycold" composition. The company specializes in the research and development and production of pvd coating equipment. It has an experienced technical team and a high-quality after-sales service team to solve any problems you encounter during the use of the equipment. Below, the composition of each part of the pvd coating machine and its working principle are introduced in detail.

Vacuum main body: The size of the vacuum chamber varies according to the requirements of the processed products. At present, the most widely used diameters are 1.3M, 0.9M, 1.5M, 1.8M, etc. The chamber is made of stainless steel stainless steel The material is required to be free from rust and solid, etc. Each part of the vacuum chamber has a connection valve to connect each air pump. Auxiliary air extraction system: The air extraction system is an important part of the vacuum system of the coating machine, mainly composed of mechanical pumps. , booster pump (mainly introduces roots pump), oil diffusion pump. This exhaust system is composed of "diffusion pump + mechanical pump + roots pump + low temperature cold trap + polycold". The exhaust process is: mechanical The pump first evacuates the vacuum chamber to a low vacuum state of less than 2.0*10-2PA, which provides the premise for the subsequent vacuuming of the diffusion pump. Then, when the diffusion pump evacuates the vacuum chamber, the mechanical pump cooperates with the oil diffusion pump to form a series connection. way to complete the pumping action.

       Mechanical pump: also known as the backing pump, the mechanical pump is the most widely used low vacuum pump. It uses oil to maintain the sealing effect and relies on mechanical methods to continuously change the volume of the suction cavity in the pump to make the pumped container. The volume of the gas inside expands continuously to obtain a vacuum.
      1. Classification of mechanical pumps: There are many kinds of mechanical pumps, commonly used are slide valve type (this is mainly used in large equipment), piston reciprocating type, fixed plate type and rotary vane type (this is currently the most widely used, this article mainly introduces) Four types.
      2. The mechanical pump starts to work from the atmosphere, and its main parameters are the ultimate vacuum and the pumping rate, which are the important basis for the design and selection of the mechanical pump. The single-stage pump can pump the container from the atmosphere to the ultimate vacuum of 1.0*10-1PA, and the two-stage mechanical pump can pump the container from the atmosphere to 6.7*10-2Pa, or even higher. The pumping rate refers to the volume of gas that can be discharged per unit time when the rotary vane pump operates at the rated number of revolutions. It can be calculated by the following formula: Sth=2nVs=2nfsL fs represents the cross-sectional area of the cavity at the end of suction, and L represents the empty space. The length of the cavity, the coefficient means that the rotor has two exhausting processes every one rotation, Vs means that when the rotor is in a horizontal position, the suction ends, the volume in the cavity is the largest at this time, and the speed is n. The exhaust effect of the mechanical pump is also related to the speed of the motor and the tightness of the belt. When the belt of the motor is relatively loose and the speed of the motor is very slow, the exhaust effect of the mechanical pump will also deteriorate, so it is necessary to maintain it frequently. Inspection, the sealing effect of the mechanical pump oil also needs to be checked frequently. If the oil is too small, the sealing effect will not be achieved, and the pump will leak air. The oil level should be 0.5 cm below the line.
      3. Mechanical pumps are often used to remove dry air, but cannot remove gases with high oxygen content, explosive and corrosive gases. Mechanical pumps are generally used to remove permanent gases, but they have no effect on moisture. Good effect, so it can't pump out moisture. The main parts of the rotary vane pump are the stator, rotor, shrapnel, etc. The rotor is inside the stator but has a different mandrel from the stator, like two inscribed circles. It is ensured that the shrapnel is tightly attached to the inner wall of the stator.