JPH0211656Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an improvement of a sliding ring that is a component of a mechanical seal related to shaft sealing technology.

[Conventional technology]

A mechanical seal having sliding rings airtightly fixed to a rotating shaft side and a non-rotating device housing side, respectively, and sealing the rotating shaft by sliding the sliding rings closely against each other. In recent years, sliding rings made of ceramic, which has excellent heat resistance, wear resistance, corrosion resistance, and electrical insulation, and silicon carbide, which has excellent heat resistance, wear resistance, corrosion resistance, and appropriate conductivity, have been widely used. ing.

FIG. 3 schematically shows an example of this type of sliding ring, which includes a sliding ring main body a made of ceramic, silicon carbide, etc., and a means such as shrink fitting on the outer peripheral surface of the main body a. It is composed of a metal annular reinforcing ring b fitted by.

[Problem that the invention attempts to solve]

However, according to the above configuration, since ceramics, silicon carbide, etc. are relatively brittle materials, if the interference between the sliding ring main body a and the reinforcing ring b is large, the sliding ring will be damaged due to excessive fitting stress. If a crack occurs in a and the interference is small, there is a problem that the fitting force between a and b is lost under high temperature conditions, making it unusable.

[Means for solving problems]

The present invention has been made to solve the above-mentioned problems, and provides a sliding ring for a mechanical seal in which a reinforcing ring is fitted onto the outer peripheral surface of a sliding ring main body made of a relatively brittle material. is cut at one point in the circumferential direction, and the surface of the inner circumferential surface of the reinforcing ring that corresponds to the seal mounting recess formed on the inner circumferential surface of the sliding ring main body on the side opposite to the sliding surface is cut at one point in the circumferential direction. The structure is such that the stepped surface does not come into contact with the outer peripheral surface of the main body.

[Effect]

In other words, by cutting the reinforcing ring at one point in the circumferential direction, the reinforcing ring has appropriate elasticity in the radial direction, and the stress caused by shrink fitting is alleviated, so that the sliding ring body and the reinforcing ring are It is possible to set a large tightening allowance.

Moreover, the stress does not act on the non-sliding surface side of the sliding ring main body, which is thin in the radial direction due to the seal mounting recess.

〔Example〕

Next, an embodiment of the sliding ring of the mechanical seal according to the present invention will be described with reference to FIGS. 1 and 2.

In FIG. 1, 1 is a sliding ring body made of ceramic, silicon carbide, etc., and 2 is the main body 1.
This is a reinforcing ring made of steel or the like that is shrink-fitted onto the outer peripheral surface of the ring. The reinforcing ring 2 has a cut portion 3 at one location in the circumferential direction.

Because of this cutting portion 3, the reinforcing ring 2 has appropriate elasticity in the radial direction as shown in FIG. The stress generated in the sliding ring body 1 is relaxed.

Furthermore, a stepped surface 5 is formed on the inner circumferential surface of the reinforcing ring 2 on the side corresponding to the seal mounting recess 4 formed on the inner circumference of the sliding ring main body 1 on the opposite side to the sliding surface 1a. The stepped surface 5 is not in contact with the outer circumferential surface of the sliding ring main body 1, and the fitting pressure is applied to the anti-sliding surface side portion 1b which is radially thin and has low strength due to the packing mounting recess 4. It seems like it doesn't work anymore.

[Effect of idea]

As described above, the sliding ring of the mechanical seal according to the present invention has a reinforcing ring that is fitted externally to the sliding ring body made of a relatively brittle material such as ceramic or silicon carbide, at one location in the circumferential direction. Since the structure is designed to alleviate the stress of cutting and fitting,
Since problems such as cracking due to excessive fitting stress do not occur in the sliding ring body, and a large tightening margin can be set, the fitting force will not be lost even under high temperature conditions. This provides an excellent effect in that the sliding ring main body can be protected without applying a destructive fitting pressure to the thin walled portion formed by the recess.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a partial cross section of a sliding ring according to an embodiment of the present invention, Fig. 2 is a front view of a reinforcing ring in the same embodiment, and Fig. 3 is a front view of a sliding ring according to a conventional example. FIG. 1... Sliding ring main body, 2... Reinforcement ring, 3... Cutting section.

Claims (1)

[Scope of utility model registration request] In a sliding ring in which a reinforcing ring is fitted onto the outer circumferential surface of a sliding ring main body made of a relatively brittle material, the reinforcing ring is cut at one point in the circumferential direction, and the inner circumferential surface of the reinforcing ring is cut off at one point in the circumferential direction. , a sliding mechanical seal characterized in that the surface corresponding to the seal mounting recess on the inner circumferential surface on the non-sliding surface side of the sliding ring body is a stepped surface that does not come into contact with the outer circumferential surface of the sliding ring body. ring.