K-800 ,KT-800 Series oil diffusion Vacuum pump
KT, K series oil diffusion pump is the main pump used to obtain high vacuum (2 ~ 10-10-5 pa)t. It can be combined with water-cooled plate, pipe, valves and mechanical vacuum pump together and becoming high vacuum system, the ultimate pressure can be up to (2 ~ 10-10-4 pa) . If it takes liquid nitrogen cooling device with baking, the vacuum can be up to the ultra high vacuum10-6 (pa).
The characteristics of the pump is strong pumping ability, Large puming capacity from 480 to 130000 l/s are suitable. It has Observation window, oil filling port and discharge port, pump oil measurement device. The products take stretching technology on manufacturing, reducing weld, increasing strength, reducing the discharge volume.Heater is equipped either with heating wire or electric heating plate, you can choose when you order it.
It is widely used in vacuum coating, vacuum furnace, electronics, chemical industry, aviation, aerospace, metallurgy, material, biological medicine, atomic energy, space exploration and other high-tech fields, and it has also been widely used in titanium sponge field with high praise.
Oil Diffusion Pump has K type and KT type.:
K type diffusion pump is straight cavity.
KTtypediffusion pump is convex cavity.
3. Product Application
The pump is applicable to vacuum melting,vacuum furnace, vacuum degassing, vacuum drying, vacuum coating, vacuum impregnation and Solar industries and other vacuum operations.
4. Working principle
Diffusion pumps differ from conventional mechanical pumps in that they use a high-speed jet of fluid to direct gas molecules in the pump throat, down to the bottom of the pump and out the exhaust, which is usually called the foreline. The high-speed jet is produced by boiling the fluid (such as silicone oil) and then directing the resultant vapor through a series of vertically stacked cone-shaped jet assemblies. Typically there are three jet stages of diminishing size with the largest at the bottom and the smallest at the top (Fig. 1).
The boiling oil moves upward through the jet assemblies and is expelled in a downward direction at the top of each assem-bly. Exiting from the jets, the high-energy oil droplets travel downward in the periphery of the chamber at speeds up to 335 meters per second. The vapor jets entrain gas molecules and direct them towards the exhaust port, where they are pumped away by a roughing pump. The effect of removing molecules is to create a high vacuum in the upper portion of the chamber, which is connected to the vacuum chamber. The roughing pump lowers the pressure inside the diffusion chamber to approximately 10-2 mbar or lower. This makes it possible for the diffusion pump to create a vacuum ranging from 10-3 to 10-9 mbar (10-1 to 10-7 Pa). Pumps and jet designs have evolved over the years and improved synthetic fluids have been developed, enabling the high levels of vacuum to be achieved with this pump technology. The pump external housing (or shell) is generally water-cooled to prevent thermal run-away. In all diffusion pumps, a small amount of backstreaming, or movement of oil molecules into the vacuum chamber, occurs. In many applications this is acceptable. In more critical applications an optically dense baffle is typically provided to deflect parti-cles before they can reach the process stream. A trap is placed above the baffle and cooled to a low temperature to condense hydrocarbons and water vapor from the pump chamber. Due to the possibility of backstreaming, diffusion pumps may not be suitable for use with the most sensitive analytical equipment.
5. Structure characteristics
The diffusion pump main part including pump shell,pump core, evaporation boiler,heater, cooling water pipe and so on.
KT series pump shell is made to convex cavity shape between the first stage nozzle and the second stage nozzle, to increase the pumping speed.
The pump shell is mainly used for installing pump core, cutting off the air completely, condensing the oil vapor. the surface inside is polished.The pump core is made up of multiple nozzle and vapour pipe, and is fixed in the pump shell.