JPS6271530A - Ultrahigh vacuum flange - Google Patents

Abstract

PURPOSE:To fix a clamping ring after a seal ring is welded to a pipeline by providing a screw on the part having larger diameter than the diameter of a gasket and making the seal ring part and the clamping ring part freely attachable and detachable. CONSTITUTION:A screw 12 is provided on the part having larger diameter than the diameter of a gasket 11 and a clamping ring 13 can be fastened to a seal ring 14 by the screw. Consequently, the clamping ring can be freely rotated in accordance with the position of a clamping screw hole of the counter flange. Moreover, the clamping ring can be fixed after the seal ring is welded to a pipeline, hence the operability and performance are improved and further the edge part can be advantageously repaired by detaching the clamping flange.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an improvement in the structure of an ultra-high vacuum flange.

[Background of the invention]

As a vacuum flange that can be baked out under an ultra-high vacuum (10" TOrr (10-'Pa)), a metal gasket made of copper or the like is commonly used, commonly known as a conflat flange. This is shown in Figure 1. By tightening the conflat flanges 1 with several tightening screws 2, the edges 3 sink into the gasket 4, and the metal gasket (vacuum is released due to reaction force from the outer diameter). It will be sealed.

When making piping for vacuum equipment using these vacuum flanges, one side of the vacuum flange should be attached to a normal Integral flange 1, the opposite side is
A so-called rotary flange 5 is generally constructed in which a portion into which a tightening screw is inserted is used as a tightening ring 6 and is separated from a seal ring edge portion (9) so that it can freely rotate in the circumferential direction. The purpose of this is to prevent leakage from the seal portion due to unbalanced tightening force caused by forcibly tightening the flanges without matching the positions of the tightening screw holes.

However, as shown in Figure 1, after the seal ring is welded to the piping, the tightening ring cannot be inserted, so if the work instructions are not followed thoroughly or the tightening ring is forgotten due to carelessness during welding work, etc. There was a risk of re-welding. (9) Due to the influence of heat during welding and ease of work, it is common to weld by shifting the tightening/g in the axial direction, but if the branch pipe is attached at right angles, In that case, it was not possible. Furthermore, damage to the edge is fatal to the vacuum seal performance, so when you try to repair it later, there are disadvantages such as the tightening ring getting in the way and repair work being difficult. Just be sure to shave off the flange end face (tightening ring end face) as well.

[Purpose of the invention]

The present invention eliminates these drawbacks and provides an ultra-high vacuum rotating flange, i.e., a tightening ring is inserted after welding, and
The objective is to provide a vacuum flange in which the clamping ring is freely rotatable.

[Summary of the invention]

According to the present invention, a screw is provided on the outer diameter portion rather than the seal portion, and the tightening ring can be removed using the screw.

[Embodiments of the invention]

An example will be shown in which the vacuum flange according to the present invention is used for vacuum piping of an analytical device. That is, as shown in FIG.
2 is provided, and the tightening ring 13 is coupled to the seal ring 14 by the screw thereof. The tightening ring can be freely rotated according to the position of the tightening screw hole of the mating flange. Of course, during this rotation, the tightening ring moves in and out in the axial direction, but the amount is
The pitch of the screws was 0.5 m, and there were 6 tightening screws, so the maximum is 1/12 of 0.5 fi.
Considering the thickness of the gasket and the tightening force, this amount is not a problem. (Actually, it is rotated in the direction that increases the flange spacing.) Also, gasket tightening force acts on the screw, but the stress applied to the screw is approximately 5 kg/-, so there is no problem with strength or deformation. .

In this embodiment, a step is provided at the threaded portion, the small diameter of which is equal to the diameter of the gasket, but this serves to guide the axial movement of the screw and is not essential. . Providing threads with a diameter larger than the gasket diameter throughout the flange thickness also serves the purpose.

〔Effect of the invention〕

According to the implementation of the present invention, many effects as described below can be obtained as a result of such a structure.

(1) It is no longer necessary to insert a tightening ring before welding the seal ring to the pipe, making it easier to weld and allowing welding to be performed without applying additional heat to the pipe, improving work efficiency. Improved performance.

(2) The edge can be repaired by removing the tightening flange, making it much easier to repair, and it is no longer necessary to process the end face of the tightening ring at the same time.

(3) Since conventional flanges receive the tightening force of the seal part as shearing force and bending force at the shoulder of the tightening ring (Fig. 1, 8), a certain degree of thickness is required, and as a result, The integrated flange is also thicker, but according to the present invention, the load receiving part can be provided in the seal ring (Fig. 2, 14), so it is possible to do this with a flange of the same thickness. This is advantageous in terms of saving material costs, etc.

(4) When baking is performed to achieve an ultra-high vacuum, the gasket and flange may come into close contact with each other, making it difficult to remove them when replacing them. However, according to the structure of the present invention, by turning the tightening ring, It applies force, so it's easy to remove.

(5) By changing the distance between the tightening ring and the flange end face, the amount of gasket deformation at the edge can be changed.
Can accommodate slight changes in gasket thickness.

'6) It is clear from the above explanation that both flanges on both sides can be constructed of rotating flanges according to the present invention. There is no need for a large hole diameter as in the conventional case.

[Brief explanation of drawings]

FIG. 11 is a longitudinal sectional view showing a conventional flange structure, and FIG. 2 is a longitudinal sectional view showing a flange structure according to an embodiment of the present invention. 1... Ninflat flange, 2... Tightening screw, 3
... Edge, 4... Gasket, 5... Rotating flange, 6... Tightening ring, 7... Piping, 8... Tightening ring shoulder, 9... Paseal ring, 11 ...Gasket, 12...Screw, 13...Tightening ring, 14
···Seal ring. Tomi 1 figure

Claims (1)

[Claims] 1. In an ultra-high vacuum flange that is vacuum-sealed by tightening a metal gasket made of copper or the like with a flange with a convex edge, the edge portion and the tightening ring are attached to the gasket. An ultra-high vacuum flange that makes it possible to separate the edge part and the tightening ring by loosening and removing the screws, which are connected by a screw with a diameter larger than the diameter of the flange. 2. Item 1: By rotating the tightening ring, the tightening screw hole of the integrated mating flange and the tightening screw hole of the flange tightening ring can be aligned and held at that position. Ultra-high vacuum flange as described. 3. The ultra-high vacuum flange according to item 1, wherein the amount of edge deformation with respect to the gasket can be changed by rotating the tightening ring.