The Roots blower used in the oil blending workshop in a plant in Henan Oilfield, with the model SD36*28, is a product produced by Changsha Blower Factory in 1995 and has been used for more than 10 years. In recent years, it had such faults as great vibration, skeleton seal leakage, difficult barring, impact of rotor, reduced outlet wind pressure and reduced air volume.

Our improvement experts went to the plant and, with the vibration analyzer, found that the 2X frequency component in the spectrum was too high, thus concluding that there was something wrong with the blade installation gap and collision existed. After dismantling, it was found that the drive shaft and the driven shaft were severely worn, and the bearings and gears were also worn.

Due to long-term service of the fan, most of the equipment had been aging, with too many parts to be replaced. Finally, it was decided to re-purchase a brand new three-leaf Roots blower instead of repairing the old one. The installation test produced good effect, high efficiency and small noise.