Abstract: In order to look for a new way of reciprocating seal, the study on the reciprocating seal of piston ring in 2D25W-69/2.2～8.8 compressor is carried out. Firstly the defects of the traditional reciprocating seals and magnetic fluid seal are analyzed and the viewpoint of the combined reciprocating seal structure is proposed. In view of the real work condition of 2D25W-69/2.2～8.8 compressor, three kinds of combined magnetic fluid reciprocating seal structures, three-inclined cut packing rings and magnetic fluid seal, C-shape slip ring and magnetic fluid seal and improved C-shape slip ring and magnetic fluid seal, are designed. Then the magnetic field distribution and the anti-pressure capacity of the above three seal structures are analyzed theoretically. And the test bed of magnetic fluid reciprocating seal is designed and manufactured. Then the seal performances of the three reciprocate seal structures are tested. The test results indicate that the improved C-shape slip ring and magnetic fluid seal structure has certain practical value.

Key words: Magnetic fluid, Mechanical design, Pressure, Seal