The invention discloses an orifice sealing part which comprises a sealing ring. The orifice sealing part is characterized by further comprising a framework, wherein a closing part is connected with one side surface of an opening of the sealing ring; a circle of flange which exceeds the outer surface of the sealing ring is arranged on the outer surface of the closing part; the framework is arranged inside the closing part and the sealing ring; the framework is a U-shaped framework; the U-shaped framework comprises a top part and an extended part; the top part is arranged inside the closing part; the extended part which is formed in the way that the top part extends downwards extends into the sealing ring. By adopting the orifice sealing part, the problems in the prior art that relatively great trouble can be caused to sealing and application as sealing parts are very likely to drop off and are complicated to mount and dismount when being mounted inside oil holes due to relatively small diameter and depth of the oil holes are solved, and the orifice sealing part is simple in structure, high in strength, not easy to drop off and convenient to mount and dismount.