In order to improve the pressure capability of Magnetorheological fluid (MRF) reciprocating seal with four
magnetic sources, MRF reciprocating seal structure was designed based on the formula of MRF reciprocating
seal. The magnetic field distributons in the sealing gap of MRF reciprocating seals were analyzed by using finite
element analysis of magnetic field. The influences of structure parameters such as sealing gap, ratio of
permanent magnet height to length, ratio of pole tooth length to width, ratio of slot width to pole tooth width
and ratio of pole piece height to the shaft radius on the sealing capabilities were studied. The results were
analyzed and discussed. The results show that the pressure capability of MRF seal decreases significantly with
the increase of sealing gap. The pressure capability of the MRF seal increases firstly and then decreases with
the increase in the ratio of permanent magnet height to its length. The pressure capability of the MRF seal
increases firstly and then decreases with the increase in the ratio of pole tooth length to its width. The pressure
capability of the MRF seal increases firstly and then decreases with the increase in the ratio of slot width to pole
teeth width. The pressure capability of MRF seal decreases with the increase in the ratio of pole piece height to
shaft radius.