JP2002202231A - Fixing device for pressure test for cylindrical component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To preclude an axis-directional tensile load from acting on a cylindrical component, in a pressure test for the cylindrical component. SOLUTION: A fixing ring 4 is set in the central part on a base plate 2, and a lower end of the cylindrical component is fixed in an upper end of the ring 4. A shield frame 7 is erected in an outer circumferential part on the base plate 2, and an upper end opening of the shield frame 7 is closed removably with a lid. A support ring 11 is attached to a lower face of the lid, and a dummy casing 12 attached to an upper end of the cylindrical component is engaged with a lower end part of the support ring 11 via an O-ring 13 to be freely slidable along the axial direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing device used for performing a pressure test on a cylindrical component to which no axial tensile load is applied.

[0002]

2. Description of the Related Art In various types of pressure vessels, when an outer wall portion of the pressure vessel is constituted by a cylindrical part, usually,
A pressure test is performed to confirm the pressure resistance of the cylindrical component.

[0003] Fig. 2 shows a procedure of a pressure test of a cylindrical part which is generally carried out. The openings at both ends in the axial direction of the cylindrical part a are closed with lids b and c to form a closed container structure. , A pressure test is performed by applying a pressure P inside the cylindrical part a.

[0004]

However, in the pressure resistance test as shown in FIG. 2, an axial tensile load T acts on the cylindrical part a due to an expansion load acting on the inside of the closed vessel structure. When the component a is, for example, a casing of a gas turbine, there is a problem that an accurate pressure resistance cannot be applied.

That is, in the case of a gas turbine casing, there are compressor blades for increasing the pressure inside the casing and turbine blades that work by using the internal pressure before and after the casing. The shaft is not directly connected to the casing, but is subjected to an axial tensile load generated by the pressure acting on the compressor blade and the turbine blade. Therefore, no axial tensile load acts on the casing,
When the pressure test is performed as shown in FIG. 2, an excessive load is applied to the casing, and the pressure test is not proper.

Accordingly, an object of the present invention is to provide a fixing device for a pressure resistance test of a cylindrical part which is suitable for performing a pressure resistance test on a cylindrical part to which no axial tensile load is applied.

[0007]

According to the present invention, in order to solve the above-mentioned problems, a cylindrical shield frame having a required height is erected on an outer peripheral portion on a base plate, and is provided at an upper end opening of the shield frame. A lid is detachably attached, and a fixing ring for detachably attaching the lower end of the cylindrical component is installed on a base plate located inside the shield frame. The lower surface of the lid is substantially the same as the cylindrical component. The upper end of the support ring having a diameter is fixed, and a dummy casing for detachably attaching to the lower end of the support ring is detachably attached to the upper end of the cylindrical component in the axial direction of the cylindrical component via an O-ring. It is movably fitted, and the inside pressure test space is sealed in the area surrounded by the base plate, the fixing ring, the cylindrical part, the dummy casing, the support ring, and the lid. And it was configured so as to form a.

When an internal pressure is applied to the inner pressure test space, the axial extension force based on the expansion load is absorbed by the relative sliding displacement between the dummy casing and the support ring in the axial direction. No axial tensile load acts, and only a radial expansion load acts.

In addition, outside the inner pressure resistance test space, a portion surrounded by the shield frame, the base plate, and the lid,
In a case where a closed outer pressure test space is formed, a pressure test of the cylindrical component can be performed by an external pressure.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1A and 1B show an embodiment of the present invention, and show a case where a casing 1 of a gas turbine is used as a cylindrical component. That is, a circular gantry 3 having a required height is installed at a central portion on a circular base plate 2, and an outer peripheral portion on the gantry 3 has a diameter corresponding to the diameter of the casing 1 and an upper end portion. A low-height fixed ring 4 having a mounting flange 4a provided on the outer periphery is installed. And 4a are sandwiched by a sealing material 5 and connected by bolts 6 so that the casing 1
And has a cylindrical shape on the outer peripheral portion of the base plate 2 so as to reach a position higher than the height position of the casing 1 disposed on the fixing ring 4 on the gantry 3. A shield frame 7 is erected, and the casing 1 is placed at the upper end opening of the shield frame 7.
The outer peripheral portion of the ring-shaped outer lid 8 formed at the center with an opening 8a larger than the diameter of the outer lid 8 is attached, and a circular center lid 9 is placed on the opening 8a of the ring-shaped outer lid 8 by bolts 10. A cylindrical support ring 11, which is detachably attached and whose lower end extends to near the upper end of the casing 1, is sandwiched between the lids 8 and 9 at the lower surface of the central lid 9. Fixed
Further, a dummy casing 12 provided with a mounting flange 12a corresponding to the mounting flange 1a at the upper end of the casing 1 on the outer periphery of the lower end is placed on the casing 1, and the mounting flanges 1a and 12a are sandwiched by the sealing material 5. Between the inner peripheral surface of the upper end of the dummy casing 12 and the outer peripheral surface of the lower end of the support ring 11.
The casing 13 is slidably fitted in the up-down direction which is the axial direction of the casing 1 with the ring 13 interposed therebetween.

In the above configuration, the portion where the gantry 3 contacts the base plate 2 and the fixing ring 4, the support ring 1
Although not shown, a sealing material is interposed between a portion where the flange 11a contacts the outer lid 8 and the center lid 9 and a portion where the shield frame 7 contacts the base plate 2 and the outer lid 8, respectively. As a result, a sealed inner pressure test space 14a is formed in a portion surrounded by the fixing ring 4, the casing 1, the dummy casing 12, and the support ring 11 between the gantry 3 and the center lid 9, and the base plate 2 and the shield are formed outside the sealed pressure test space 14a. Frame 7 and outer lid 8
Pressure test space 14 sealed in a portion surrounded by
b is formed. A pressure fluid pipe 15a for supplying a pressure fluid for a pressure test to the inner pressure test space 14a is provided on the gantry 3 from below the base plate 2 through the lower part of the gantry 3 of the base plate 2. In addition to being guided to the supply port 16, the detachable plug 1 is inserted through the base plate 2 through the pressure fluid pipe 15 a.
7, a pressure fluid supply port 19 having a detachable plug 18 is provided at a position corresponding to the outer pressure test space 14b of the base plate 2, and a pressure fluid pipe 15b is guided to the detachable plug 18.

In FIG. 1A, reference numerals 20 denote pressure gauges.

When the pressure test of the casing 1 of the turbine is carried out by the internal pressure, the center lid 9, the support ring 11, the outer lid 8, and the shield frame 7 are detached, and the upper end is previously attached. The casing 1 in which the dummy casing 12 is mounted on the flange 1a via the mounting flange 12a with the bolts 6 is attached to the mounting flange 1b at the lower end by the bolt 6 to the mounting flange 4a at the upper end of the fixing ring 4 on the gantry 3. After being mounted, the casing 1 is fixedly arranged on the gantry 3 via the fixing ring 4.

Next, the shield frame 7 is attached to the base plate 2, and the outer lid 8 is fixed to the upper end of the shield frame 7.

Next, the removed center cover 9 is placed on the opening 8a of the outer cover 8 and attached by bolts 10. At this time, the lower end of the support ring 11 fixed to the lower surface of the center cover 9 Is fitted to the inner peripheral portion of the dummy casing 12. Thereby, the inner pressure test space 14 a of the casing 1 is formed above the gantry 3.

After this state, the pressure fluid piping 15a
Pressure fluid (water or air) introduced through the cradle 3 is supplied from the pressure fluid supply port 16 of the gantry 3 to the inner pressure test space 14a,
For example, a pressure of 8 to 10 MPa is applied.

In the above description, an internal pressure causes an expansion load along the axial direction and a radial expansion load of the casing 1 to act on the member forming the inner pressure test space 14a. Since the shaft 12 is slidably fitted in the axial direction, the extension force due to the axial expansion load is absorbed by the relative sliding displacement of the support ring 11 and the dummy casing 12 in the axial direction. At this time, since the O-ring 13 is interposed between the outer peripheral surface of the lower end portion of the support ring 11 and the inner peripheral surface of the dummy casing 12 in the fitted state, the pressure fluid does not leak from between the two. Therefore, a radial expansion load acts on the casing 1, but an axial tensile load does not act, and an excessive load is not applied. Therefore, a pressure resistance test with an appropriate load can be performed.

Next, when the pressure test of the casing 1 needs to be performed by the external pressure, the outer pressure test space 1 is required.
A pressure fluid is supplied to 4b through a pressure fluid pipe 15b, and a pressure of, for example, about 1 MPa is applied. At this time, the central lid 9 may be removed.

Also in this case, the extension force along the axial direction of the casing 1 is absorbed by the relative sliding displacement in the axial direction of the support ring 11 and the dummy casing 12 via the O-ring 13 as in the case of the internal pressure test. Therefore, no tensile load acts on the casing 1 in the axial direction, and the pressure test can be performed with an appropriate pressure load.

Note that the lid attached to the upper end opening of the shield frame 7 does not necessarily need to be separated into the outer lid 8 and the central lid 9, but may be integrated.
The arrangement relationship between the inside and outside of the support ring 11 and the dummy casing 12 may be reversed. Further, the present invention can be similarly applied to cylindrical parts other than the turbine casing 1, and other ranges that do not depart from the gist of the present invention. It is needless to say that various changes can be made within.

[0022]

As described above, according to the fixing device for a pressure resistance test of a cylindrical part of the present invention, a cylindrical shield frame having a required height is erected on the outer peripheral portion on a base plate, and the shield frame is provided. A lid is detachably attached to an upper end opening of the cylindrical component, and a fixing ring for detachably attaching a lower end of the cylindrical component is installed on a base plate located inside the shield frame. A dummy casing for fixing the upper end of a support ring having substantially the same diameter as the cylindrical part and detachably attaching the lower end of the support ring to the upper end of the cylindrical part,
The base plate, the fixing ring, the cylindrical part, and the cylindrical part are slidably fitted in the axial direction of the cylindrical part via the ring.
The inner casing is designed to form a sealed inner pressure test space in the area surrounded by the dummy casing, the support ring, and the lid. Therefore, when internal pressure acts on the inner pressure test space, the cylindrical component expands in the axial direction. The elongation force due to the load can be absorbed by the relative sliding displacement of the dummy casing and the support ring in the axial direction, without applying an axial tensile load to the cylindrical part,
This allows a pressure test to be performed with an appropriate load on the cylindrical component, and a sealed outer pressure test is performed outside the inner pressure test space in a portion surrounded by the shield frame, the base plate, and the lid. With such a configuration that the space is formed, an excellent effect that a pressure resistance test by an external pressure can be performed with an appropriate load on the cylindrical component is exhibited.

[Brief description of the drawings]

FIG. 1 shows an embodiment of a fixing device for a pressure resistance test of a cylindrical part of the present invention, wherein (a) is a cut side view, and (b).
FIG. 2 is an enlarged view of a part A of FIG.

FIG. 2 is a schematic view showing a conventional pressure test procedure for a cylindrical component.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Casing (cylindrical part) 2 Base plate 3 Stand 4 Fixing ring 7 Shield frame 8 Outer lid (lid) 9 Center lid (lid) 11 Support ring 12 Dummy casing 13 O-ring 14a Inner pressure test space 14b Outer pressure test space

Claims (2)

[Claims] 1. A cylindrical shield frame having a required height is erected on an outer peripheral portion of a base plate, a lid is detachably attached to an upper end opening of the shield frame, and a base plate located inside the shield frame is provided. A fixing ring for detachably attaching the lower end of the cylindrical part is installed on the upper part, and the upper end of a support ring having substantially the same diameter as the cylindrical part is fixed to the lower surface of the lid, and the lower end of the support ring is fixed. A dummy casing for detachably attaching to an upper end portion of the cylindrical part is slidably fitted in the axial direction of the cylindrical part via an O-ring, and the base plate, the fixing ring, and the cylindrical part Characterized in that a sealed inner pressure test space is formed in a portion surrounded by the dummy casing, the support ring, and the lid. Fixing device for pressure test of cylindrical parts. 2. A pressure test for a cylindrical part according to claim 1, wherein a sealed outer pressure test space is formed outside the inner pressure test space and surrounded by the shield frame, the base plate and the lid. Fixing device.