What are the design requirements for Roots fans at different temperatures (ambient and high)? BelowRoots FansI'll take you through it.
One, it's the sealing of high temperature gases
The high temperature gas seal adopts double-sided mechanical seal, which not only has good sealing performance, but also meets the requirement of medium sealing performance, and the circulating fluid sealant can take away part of the heat conduction through the diaphragm. The heat generated by itself keeps the fan bearings, gears and other transmission parts that require low-temperature operation in good working condition. In addition to the suitability of the medium for the sealing material, the suitability for high temperatures is also considered. The machine seals are made of corrosion-resistant, high-temperature-resistant metal materials and perfluoroether material O-rings.
Second, the design of the insulation structure
In order to minimize the effect of high temperature gases on the lubrication drive of the Roots fan, it is necessary to consider insulation measures in the structural design. Adding side panels to the bulkheads at both ends of the fan and adding insulation between the side panels and the bulkheads - thermal insulating gaskets, which have a low thermal conductivity, are effective in reducing the heat transfer from the machine chamber to the ends. At the same time, thermal insulating gaskets are also used between the wall panels and the partitions to minimize the heat transfer from the partitions to the wall panels. The choice of this type of thermal structure and insulation material is beneficial in reducing the heat transfer from the gas heat to the mechanical drive section.
III. Ancillary cooling measures
Heat transfer is inevitable even if good insulation does not achieve thermal insulation. Under the influence of high temperatures, part of the heat will continuously pass through the air chamber and rotor source to the machine seals, wall plates, bearings, oil tanks and gears. Transmission. In order to ensure the reliable operation of the fan, the wall panels on both sides of the Roots fan are changed from the traditional closed structure to an open structure, which further reduces the wall and shaft temperatures through air convection. The main and auxiliary oil tanks are reinforced with water-cooled casing structure for full heat exchange to reduce the lubricant temperature.
IV. Matching of parts and clearance between impellers
The proper sizing of Roots fan components should take into account the effects of temperature. Casing clearances, impeller clearances, wall clearances and fan gear clearances are important design points in the design and manufacture of Roots Fans. The temperature fields of the components are very different when comparing a high temperature application of a Roots fan to room temperature. The impact on the design of each clearance is also significant.
V. High temperature materials
The main components of the high temperature gas overflow are made of high performance ductile iron, the O-rings are made of perfluoroether and the surfaces of the parts are made of high temperature resistant coatings. Temperature adaptability considerations are used to select other components such as oil seals, bearings and lubricants.