JP3264826B2 - Pressure vessel cap screwing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure test apparatus for a pressure vessel, and more particularly, to a cap screwing apparatus for screw-fitting a screw joint for connecting and fixing a lid of a test tank to a cap of the pressure vessel.

2. Description of the Related Art As disclosed in, for example, Japanese Patent Application Laid-Open No. Hei 7-110292 (see FIG. 3), a clamp device for fixing and supporting a pressure vessel in an upright posture and the pressure vessel are disclosed. And an elevating device (air cylinder) disposed above the air conditioner. The elevating device is provided with a screw joint for screwing into a base of the pressure vessel, and means for rotating the screw joint.

However, since the above conventional screwing device for a base is rotatably mounted on the elevating device, the base of the clamped pressure vessel and the axis of the screw joint are displaced. In the case or when the base is inclined and welded to the container body, the screw joint is not accurately fitted to the screw part of the base, causing leakage from the base or damaging the screw part of the base. There was something to do. In addition, the screw portion may be damaged by an impact when the screw joint comes into contact with the base. The present invention has been made in view of the above circumstances, it is possible to absorb the misalignment of the screw joint with respect to the base of the pressure vessel, and to accurately screw-fit the base.
It is another object of the present invention to provide a cap screwing device capable of reducing an impact when the screw joint comes into contact with the cap.

In order to achieve the above object, the present invention comprises a clamp device for fixedly supporting a pressure vessel in an upright posture, and an elevating device arranged above the pressure vessel. A lower end of a support shaft mounted to be vertically movable with respect to the elevating device, in a base screw-in device in which a screw joint screwed into a base of the pressure vessel is mounted on the elevating device, and a rotation driving means for the screw joint. To
Two sets of flexible shaft couplings are connected, and the outer circumferences of the two flexible shaft couplings
A coil spring is wound around the portion in a tight contact state, the screw joint is rotatably connected to the lower end portions of the two flexible shaft joints, and the rotation driving means is attached. . The support shaft penetrates a sleeve bearing fixed to a lower end of the elevating device and is slidably mounted vertically, and a compression spring is provided between a flange portion provided at an upper end of the support shaft and the sleeve bearing. Preferably, it is interposed.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a pressure test apparatus 1 for a pressure vessel provided with a mouthpiece screwing device according to the present invention, and FIG. 2 is a longitudinal enlarged front view of a main part of the mouthpiece screwing device. In the pressure resistance test apparatus 1, a carrier 3 reciprocating in the lateral direction of FIG. 1 is mounted on a base 2, and is mounted on the carrier 3 at an intermediate portion of a column 4 erected on the base 2 to a test position. A clamp device 5 for fixedly supporting the moved pressure vessel A in an upright posture is provided. An arm 6 projects horizontally from the upper end of the column 4, and an air cylinder 7, which is an elevating device of a cap screwing device 10 described later, is vertically installed on the arm 6. Further, a test water tank 9 is installed below the base 2 so as to face the air cylinder 7 and to be substantially coaxial. The base screwing device 10 includes:
The air cylinder 7 is mounted on a mounting bracket 11 fixed to a lower end of a piston rod 8. The mounting bracket 11 can move up and down along the column 4 in a posture where the mounting bracket 11 is stopped from rotating by the column 4. A sleeve bearing 12 is fixed to the mounting bracket 11, and a flange portion 14 is provided at an upper end protruding portion of a support shaft 13 formed of a spline shaft which is slidably fitted up and down through the sleeve bearing 12. A compression spring 15 is interposed between the flange portion 14 and the sleeve bearing. The mounting bracket 11 operates in response to the upward movement of the flange portion 14 and detects a rising movement of the support shaft 13.
Is provided. On the other hand, two sets of flexible shaft joints 18 are connected to the lower end of the support shaft 13 via a pivot pin 17, and the lower flexible shaft joint 18 is connected to the bearing housing via the pivot pin 19. 20 are connected. Further, a coil spring 21 is wound around the outer circumferences of the two sets of flexible shaft couplings 18 in close contact with each other to prevent the two flexible shaft couplings 18 from buckling when a compressive load is applied. Preventing. The bearing housing 20 is provided with a pressurized introduction chamber 23 having a compressed air supply port 22 and a bearing portion 24. A boss portion 27 a of a large gear 27 fitted and fixed to a rotating shaft 26 of a screw joint 25 is provided. The rotating shaft 26 is rotatably supported by the bearing portion 24, and the upper end of the rotating shaft 26 protrudes into the pressure introducing chamber 23. The lid 28 of the water tank 9 is fitted and fixed to the rotating shaft 26. . A tapered guide 2 is provided at the lower end of the threaded joint 25.
9 are protruded. On the other hand, a bracket 30 projecting in the lateral direction is fixed to the outer side of the bearing housing 20, and an air motor 31 is mounted on the bracket 30, and the pinion 3 fitted to a rotary drive shaft 32 of the air motor 31 is mounted.
3 meshes with the large gear 27, and the screw joint 25 and the lid 28 are rotated via the large gear 27 and the rotating shaft 26. The screw joint 25 and the rotating shaft 2
A test fluid, for example, a water passage 34 is provided along the axis 6. The upper end of the passage 34 communicates with the pressure introduction chamber 23 through the communication hole 35, and the lower end communicates with the discharge port 36 provided in the guide portion 29. Further, both flexible shaft couplings 1
Tension springs 3
7 are connected to each other via adjustment nuts 38. The tension spring 37 is moved by the weight of the air motor 31 attached to one side of the bearing housing 20 depending on the weight of the two flexible shaft couplings 18,
18 is provided to prevent the cover 18 from bending rightward and downward. The length of the tension spring 37 can be changed by the adjustment nut 38 to adjust the spring pressure. Next, the operation of the base screwing device 10 having the above configuration will be described. Pressure vessel A that has completed the water injection process
Is mounted on the carrier 3 and moves to a predetermined position above the test water tank 9 shown in FIG. 1, the clamp device 5 is operated, and the pressure vessel A is sandwiched and fixed by both arms 5a, 5a. To support. At this time, although the base a of the pressure vessel A is temporarily centered with respect to the threaded joint 25, the axes are rarely exactly aligned, and the base a is distorted and welded to the container body. May be misaligned. In this state, the air cylinder (elevator) 7
Is activated, the entire mouthpiece screwing device 10 is lowered, and when the screw joint 25 comes into contact with the mouthpiece a, the reaction force causes the support shaft 13 to move upward through the two flexible shaft joints 18, 18, and the mouthpiece a
And the sensor 16 detects the upward movement of the flange portion 14 linked to the support shaft 13. Then, the air motor 31 operates in response to the sensor 16, and the lid 28 and the screw joint 25 integrated with the rotating shaft 26.
Is rotated. At the same time, the air cylinder (elevating device) 7 operates further downward, and the screw joint 25
Screwed into. At this time, screw joint 2
If the center 5 is misaligned or the base a is distorted, the two flexible shaft joints 18 bend freely, and the threaded joint 25 moves or tilts so as to match the axis of the base a. It moves to follow and is screwed into the base a accurately. On the other hand, the buckling of the two flexible shaft couplings 18 and 18 due to the compressive load applied during the screwing operation of the
It is prevented by the restoring force. Further, the coil spring 21 has an action of keeping the axis of the flexible shaft joint 18 straight against an unbalanced load. When the threaded joint 25 is screwed into the base a as described above, the clamp by the clamp device 5 is released, and then the air cylinder 7 is slightly moved upward to slightly raise the pressure vessel A and the base screwing device 10. In the state
The transfer table 3 is moved along the base 2 to a transfer position (to the right in FIG. 1). After that, the air cylinder (elevator) 7
Is actuated to the descending side again to lower the pressure vessel A together with the base screw-in device 10, to sink the pressure vessel A into the water tank 9, and to seal the water tank 9 with the lid 28. Subsequently, a test fluid supplied from the supply port 22 by a pressurizing device (not shown) is injected into the pressure vessel A through the passage 34 to apply pressure, and the amount of expansion is measured by a measuring device (not shown). When the measurement is completed, the pressure vessel A is transferred to the carrier 3 in the reverse order.
And prepare for the next step.

As described above, according to the present invention,
When the axis of the screw joint is displaced from the base of the pressure vessel, or even when the base is distorted and welded to the container body, the screw joint smoothly moves to follow the base and is moved. Can be screwed into the base accurately. In addition, it is possible to reduce the impact when the screw joint comes into contact with the base, and effectively prevent the screw portion of the base from being damaged by the impact. In particular, a coil spring is provided on the outer periphery of the two flexible shaft joints.
Are wound in close contact with each other,
Prevents buckling and prevents shafts of both flexible shaft joints
There is a centering effect that keeps the core straight. Further, according to the invention according to claim 3, the screw joint abuts the base,
In conjunction with this, since the ascending support shaft is detected by the sensor, the screw joint can be accurately operated regardless of the position of the base due to a difference in size of the pressure vessel.

[Brief description of the drawings]

FIG. 1 is a front view of an apparatus for testing the pressure resistance of a pressure vessel provided with a cap screwing device according to the present invention.

FIG. 2 is a longitudinal sectional enlarged front view of a main part of the base screwing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Withstand pressure test device 5 Clamping device 7 Air cylinder (elevating device) 10 Cap screwing device 12 Sleeve bearing 13 Support shaft 14 Flange part 15 Compression spring 16 Sensor 18 Flexible shaft coupling 20 Bearing housing 21 Coil spring 25 Screw joint 26 Rotating shaft 28 Lid 29 Guide part 31 Air motor

Claims (3)

(57) [Claims] A clamping device fixedly supporting the pressure vessel in an upright posture; an elevating device arranged above the pressure vessel; a screw joint screwed into a base of the pressure vessel into the elevating device; in die screwing device comprising a rotary drive means of the threaded joint is mounted, two pairs of flexible shaft coupling to the lower end of the support shaft mounted for vertical movement relative to the lifting device is connected, the two flexible Coil spring wound tightly around outer periphery of shaft coupling
The screwing device for a pressure vessel, wherein the screw joint is rotatably connected to the lower ends of the two flexible shaft joints, and the rotation driving means is attached to the joints. 2. The apparatus according to claim 2, wherein the support shaft is vertically slidably mounted through a sleeve bearing fixed to a lower end of the elevating device, and a flange provided at an upper end of the support shaft and the sleeve bearing. 2. The screw device according to claim 1, further comprising a compression spring interposed therebetween. 3. The screwing device according to claim 1, further comprising a sensor for detecting the elevation of the support shaft.