JPH0141990Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to pipe joints, particularly flexible expansion pipe joints,
A pipe joint in which a tie bolt is attached across a flexible member between both ends of a flexible pipe joint such as an expansion joint, or between opposite ends of two pipes connected via a pipe joint. Regarding.

[Conventional technology]

In conventional flexible pipe joints such as flexible expansion joints and expansion joints, as shown in FIG. In order to restrict elongation, a plurality of tie bolt insertion holes 4 are provided in mounting portions 4, 4 provided on flanges, etc. at both ends of the pipe joint 1, so that the plurality of tie bolts 2 straddle the flexible member 3.
a and is fixed to the mounting portions 4 with nuts 5 from the outside.

By using such tie bolts, the axial elongation of the pipe joint can be controlled, but if the pipe joint becomes eccentric due to ground subsidence on the side of one of the pipes to which it is connected, the tie bolt will follow and tilt. Therefore, there is a problem that the fixing portion of the tie bolt is bent, and the interval between the attachment portions provided on the flanges to which the tie bolt is attached (hereinafter referred to as attachment interval) becomes short. In order to deal with the bending of the tie bolt fixing part among the above problems, as shown in Fig. 3, a spherical washer 6 is fitted to the tie bolt 2, so that even if the tie bolt 2 is tilted, the spherical surface of the spherical washer 6 (at the attachment part) 4
The problem is solved by configuring the tie bolt fixing part to rotate while slidingly contacting the corresponding surface of the tie bolt.

However, to date, no suitable solution has been found to solve the problem of shortening the mounting interval among the above problems. If the installation interval is shortened, the distance l between the middle b pipes of pipes a and b will increase as shown by the dashed line in Figure 2.
As a result, excessive force is applied to the tubes a and b and the tie bolt 2, which may cause them to break. In order to prevent this, a method is used in which a distance corresponding to the shortening of the installation interval due to eccentricity is secured in advance as a gap between the nut 5 and the tie bolt attachment part 4 (attachment member) provided on the flange, etc., but in this case, This is an effective solution because the thrust caused by the fluid causes the downstream pipe b to move toward the downstream side, that is, in the direction of arrow A, and the gap that had been secured in case of eccentricity disappears. The current situation is that there is no such thing.

[Problems to be solved with the idea]

The present invention was developed with the aim of solving the above-mentioned problems of pipe joints using tie bolts, and the purpose of this invention is to create a joint that does not shorten the installation interval even if the tie bolts are tilted due to eccentricity of the pipe joint. This is what we are trying to provide.

[Configuration to solve the problem]

In order to achieve the above object, the present invention mounts a tie bolt between both ends of a flexible pipe joint or between opposite ends of two pipes connected via a pipe joint so as to straddle a flexible member. In a pipe fitting, a fixed taper washer is fixed on the outside in the axial direction of the tie bolt at the attachment part of the tie bolt provided at each end of the pipe fitting or pipe, with its inclined surface facing outward and the direction of inclination matching the set eccentric direction of the tie bolt. The tie bolt insertion hole is connected to the tie bolt insertion hole of the mounting portion and the fixed taper washer, and the tie bolt inserted into the tie bolt insertion hole of the fixed taper washer has an inclined surface on one side that engages with the inclined surface of the fixed taper washer, and a spherical washer. A movable taper washer having an engaging surface on the other side thereof, and a spherical washer having a partially spherical surface that engages with the engaging surface of the movable taper washer, and is fixed from the outside with a nut. It is.

[Effect]

With the above configuration, when the tie bolt is tilted, the movable taper washer slides in the eccentric direction of the tie bolt with respect to the fixed taper washer due to the rotational force of the tie bolt, and as a result, the sum of the thicknesses of both taper washers decreases due to the tie bolt in the direction parallel to the tube axis. It is equal to the decrease in the spacing between the nut mounting positions at both ends, and the mounting spacing despite the tilt of the tie bolt,
That is, the spacing between the tie bolt mounting portions provided on the flanges or the like to which the tie bolts are mounted remains unchanged compared to before the tie rod is tilted.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 and 4.

FIG. 1a is a side view showing the main parts of the pipe joint according to the present invention, and FIG. 1b is a side view of the same pipe joint when eccentric. The structure of the pipe joint other than the portion shown in FIG. 1 is the same as that shown in FIG. 2, so a description thereof will be omitted.

In FIG. 1a, on the outside in the tie bolt axial direction of the tie bolt mounting portion 4 provided on the flange of the pipe fitting 1, there is a fixed taper washer 7 with its inclined surface facing outward and its inclination direction being the same as that of the tie bolt 2. The tie bolt insertion holes 4a and 7a are connected to each other and fixed by welding or the like so as to match the set eccentric direction. A tie bolt 2 is inserted through the tie bolt insertion hole 4a and the tie bolt insertion hole 7a of the fixed taper washer 7.
The outside of the fixed taper washer 7 has a concave surface on one side that has an inclined surface 8b that has the same inclination angle as the inclined surface 7b of the fixed taper washer 7 and engages with the surface 7b, and forms a partially spherical surface. A movable taper washer 8 having an engagement surface 8c on the other side, and a spherical washer 6 having a partial spherical surface 6a that has the same radius of curvature as the engagement surface 8c of the movable taper washer 8 and engages with the engagement surface 8c. The movable taper washer 7 and the spherical washer 6 are fixed to the fixed taper washer 7 from the outside with a nut 5.

Next, the operation of this pipe joint will be explained. Pipe b (Fig. 4) is eccentric due to ground subsidence, etc., and pipe joint 1
When the tie bolt 2 tilts, as shown in FIG. Since a rotational force in the direction of arrow B is applied to the tip of the spherical washer 6, the partial spherical surface 6a of the spherical washer 6 slides along the engagement surface 8c of the movable taper washer 8, while the inclined surface 8b of the movable taper washer 8 slides along the engagement surface 8c of the movable taper washer 8. It moves in the direction of arrow C while sliding along the inclined surface 7b of No.7. Therefore, the fixed taper washer 7
The sum L of the thickness of the moving taper washer 8 is shown in Figure 1 a.
This reduction value m is a decrease in the distance n between the tip position of the spherical washer 6 and the end surface of the attachment part in the direction parallel to the tube axis (corresponding to Fig. 2/2). almost equal to Furthermore, on the pipe a side, as shown in FIG. 4, the tie bolt 2 rotates about the contact point P' as a fulcrum, and the movable taper washer 8 similarly moves. Therefore, the decrease in the distance between the nut attachment positions at both ends of the tie bolt 2 in the direction parallel to the tube axis due to the inclination of the tie bolt 2 is offset by the decrease in the sum L of the thicknesses of both tapered washers 7 and 8 at both ends, and the attachment distance is reduced. That is, the distance R (FIG. 4) between the mounting parts 4, 4 is not affected in any way.

In the above embodiment, two tie bolts 2 are provided axially symmetrically, but the present invention is not limited to this, and the number of tie bolts 2 may be one or more. However, tie bolt 2
It is preferable in terms of balance to provide an even number of them axially symmetrically. The sliding of the movable taper washer 8 can be improved by applying a suitable lubricant to each inclined surface of the fixed taper washer and the movable taper washer 8, or by treating the surface with a lubricant such as Teflon.
The degree of inclination of the inclined surfaces 7b and 8b of each taper washer 7 and 8 may be arbitrarily set according to the length of the pipe joint so that the mounting interval becomes constant during eccentricity. In the above embodiment, the direction of inclination of each taper washer 7, 8 is determined so that the tie bolt 2 is eccentric downward as the pipe b sinks; however, it is not limited to this. The direction of inclination may be determined according to the direction in which the object is tilted. In addition, in the above embodiment, the attachment parts 4, 4 of the tie bolt 2 are provided on the flanges at both ends of the pipe fitting 1, and the tie bolt 2 is provided between the flanges at both ends of the pipe fitting 1. The position where parts 4, 4 are provided is not limited to this, but the tie bolt 2 is located at the pipe joint 1.
As long as it is provided across both ends of the flexible member 3, it may be provided either on the inner or outer periphery of a pipe joint or on the inner or outer periphery of two pipes to be connected.

[Effect of idea]

As detailed above, according to the present invention, when the tie bolt is inclined, the movable taper washer slides in the eccentric direction of the tie bolt with respect to the fixed taper washer, and the movable taper washer slides between the nut mounting positions at both ends of the tie bolt in the direction parallel to the tube axis. Since the decrease in the gap is offset by the decrease in the sum of the thicknesses of both taper washers by 2L, the installation gap, that is, the gap between the attachment parts where the tie bolts are attached, does not decrease, and therefore, unreasonable force is applied to the pipe and tie bolts. I don't want to miss anything. In addition, since a spherical washer is used in combination with a set of taper washers, the fixed part of the tie bolt does not bend, resulting in an extremely simple structure that solves all the problems of pipe fittings using tie bolts that were previously solved. can be solved.

[Brief explanation of the drawing]

Fig. 1 is a side view showing the main parts of the pipe joint according to the present invention, Fig. 1a shows the non-eccentric state, Fig. 1b
Figure 2 shows the outline of a conventional pipe joint using a tie rod, Figure 3 shows a part of a conventional pipe joint using a spherical washer, and Figure 4 shows the state when eccentric. FIG. 2 is a diagram schematically showing a pipe joint of the present invention at a time. DESCRIPTION OF SYMBOLS 1... Pipe joint, 2... Tie bolt, 4... Tie bolt attachment part, 5... Nut, 6... Spherical washer, 7... Fixed taper washer, 8... Moving taper washer.

Claims (1)

[Scope of utility model registration request] In a pipe fitting in which a tie bolt is installed across a flexible member between both ends of a flexible pipe fitting or between opposite ends of two pipes connected via a pipe fitting, A fixed taper washer is fixed to the outside in the tie bolt axial direction of the tie bolt attachment part provided at each end, with its inclined surface facing outward and the direction of inclination matching the set eccentric direction of the tie bolt, so that the tie bolt insertion hole is connected and fixed. , furthermore, a tie bolt inserted into the tie bolt insertion hole of the mounting portion and the fixed taper washer;
a movable taper washer having an inclined surface on one side that engages with the inclined surface of the fixed taper washer and an engaging surface with the spherical washer on the other side; and a partial spherical surface that engages with the engaging surface of the movable taper washer. A pipe joint characterized in that a spherical washer is arranged and fixed from the outside with a nut.