JPH0118924Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a pressure vessel having a skirt-like support member for preventing a pressure vessel erected on the ground from overturning, and in particular, the present invention relates to a pressure vessel having a skirt-like support member for preventing a pressure vessel erected on the ground from falling over. This invention relates to a pressure vessel that allows flaw detection of welded parts to be performed reliably and quickly.

FIG. 1 shows a schematic view of a pressure vessel 1 and a skirt-shaped support member 2 that supports it. As is clear from the figure, when the pressure vessel 1 is subjected to an external force due to an earthquake or the like, the support member 2 supports the load at the welded part 3, so any defects that occur in the welded part must be repaired immediately. There is. Therefore, it is necessary to periodically inspect the welded part, but the
In the conventional mounting structure as shown in FIGS. 3 and 3, no flaw detection inspection is planned, so flaw detection operations are difficult. That is, in a general support member attachment part as shown in FIG. The support member 2 is welded 7, but in this case there is limited space to install the ultrasonic flaw detection sensor.
Sufficient flaw detection could not be performed, and especially in part 8, the sensor could not be inserted after the support member 2 was welded, so flaw detection could not be performed thoroughly. Furthermore, in this structure, even if a crack or the like is found in the 8th part, the supporting member is fully penetrated welded, so it is difficult to remove the supporting member in that part, and the welding cannot be repaired. Further, as shown in FIG. 3, when the ring-shaped member 9 is welded 10, the welded portion 10 is a fillet weld, so its strength is weak and cracks are likely to occur. Further, the ultrasonic waves are reflected by the non-welded surface 11, making flaw detection impossible.

Therefore, an object of the present invention is to provide a pressure vessel that has sufficient strength to support the pressure vessel and is equipped with a skirt-like support member so that flaw detection operations can be performed reliably and quickly. In a pressure vessel in which a skirt-shaped pressure vessel support member is attached to a ring-shaped member attached by welding around the body of the pressure vessel, the weld between the body of the pressure vessel and the ring-shaped member is formed by a full penetration weld. At the same time, an auxiliary plate is attached to the lower surface of the ring-shaped member via a boundary surface that can reflect ultrasonic waves, and the protrusion length of the ring-shaped member from the body of the pressure vessel is determined in the height direction of the ring-shaped member. The present invention provides a pressure vessel having a support member that is larger than twice the thickness of the support member, and further characterized in that the support member is attached to a ring-shaped member via the auxiliary plate.

An embodiment embodying the present invention will be described in detail below with reference to FIG. 4 showing a cross section of the support member attachment portion. In the figure, 12 is the pressure vessel body;
A ring-shaped member 14 having a thickness of t is completely penetrate-welded 15 to the outer circumferential surface 13, and the leg length of the welded portion 15 is α. The protrusion length T of the ring-shaped member 14 from the outer circumferential surface 13 of the pressure vessel body is determined to be slightly wider than 2t+α, for example, about 3t. An auxiliary plate 17 with a width W is provided on the lower surface of the ring-shaped member 14 via a boundary surface 16 that can reflect ultrasonic waves.
are welded 23. Skirt-shaped support member 1
8 is a welding 20,
Attached by 20. The width W of the auxiliary plate 17 is smaller than the protrusion length T of the ring-shaped member 14 so that the end portion 21 and the welded portion 15 do not overlap.

In order to perform flaw detection on the welded portion 15 between the pressure vessel body 12 and the ring-shaped member 14 in the pressure vessel described above, the ultrasonic probe 22 is placed on the upper surface of the ring-shaped member 14 and is emitted. Then, the ultrasonic signal propagates in the direction of 45 degrees to the bottom surface as shown by the broken line,
The ultrasonic wave is reflected at the interface 16 capable of reflecting, and the inside of the surface 15' of the weld 15 and the body 12
Since it passes through the center, any defects that exist during this time can be discovered. Therefore, by placing the probe at the position 22, it is possible to detect flaws on the surface 15' of the welded portion 15.
Furthermore, when the probe is placed at the position 22' shown by the two-dot chain line, the ultrasonic waves emitted in the 45-degree direction as shown by the broken line are inside the ring-shaped member 14 and the surface 15'a of the welded part 15a. Flaw detection is performed to propagate inside the body 12. Therefore, flaw detection can be performed over the entire thickness of the welded portion 15 by moving the probe from the rightmost portion 22 in a leftward direction. For flaw detection, perform the above operation around the entire circumference of the container. Since the position 22 where the probe is moved to the right most in this way is a position 2t+α to the right from the body surface 13, the protrusion length T of the ring-shaped member 14 is 2t+α.
It must be more than that.

Moreover, as a result of such flaw detection, welded parts 15, 15a
If scratches such as cracks are found on the surface of the plate, the welded part must be repaired and the support member 18 must be removed, but the support member 18 is welded 20 to the auxiliary plate 17, Further, since the auxiliary plate 17 is only welded 24 to the ring-shaped member 14 at one end, it is easy to remove the auxiliary plate 17 from the ring-shaped member 14, and repair work can be performed quickly.

As described above, the present invention forms the weld between the body of the pressure vessel and the ring-shaped member by a full-penetration weld, and also provides an interface on the lower surface of the ring-shaped member that can reflect ultrasonic waves. an auxiliary plate is attached through the support plate, the length of the ring-shaped member protruding from the body of the pressure vessel is made larger than twice the thickness of the ring-shaped member in the height direction; Since the pressure vessel has a support member that is attached to the ring-shaped member through the support plate, the probe can be reliably and efficiently covered over the entire area of the weld by simply moving the probe along the top surface of the support plate. In addition to being able to detect flaws, the welded parts are extremely strong and safe, and if flaws are found, they can be easily repaired, increasing the reliability of pressure vessels such as reactors in various chemical plants. Significantly improved.

[Brief explanation of the drawing]

Figure 1 is a schematic side view of a general pressure vessel, Figure 2
3 are side sectional views of a conventional skirt attachment part, and FIG. 4 is a side sectional view of a skirt attachment part according to an embodiment of the present invention. 1... Pressure vessel, 18... Support member, 14...
Ring-shaped member, 12...Pressure vessel body, 15, 1
5a... Full penetration welded part, 17... Auxiliary plate, 1
6... Boundary surface, 22, 22'... Probe.

Claims (1)

[Scope of utility model registration request] In a pressure vessel in which a skirt-shaped pressure vessel support member is attached to a ring-shaped member attached by welding around the body of the pressure vessel, the weld between the body of the pressure vessel and the ring-shaped member is a full penetration weld. At the same time, an auxiliary plate is attached to the lower surface of the ring-shaped member via an interface that can reflect ultrasonic waves, and the length of the ring-shaped member protruding from the body of the pressure vessel is adjusted to the height of the ring-shaped member. 1. A pressure vessel having a support member having a thickness greater than twice the thickness in the transverse direction, and further comprising: the support member being attached to a ring-shaped member via the auxiliary plate.