JP2013011555A - Tube deformation inspection tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inspection tool capable of easily checking a strain on the entire periphery of tube end.SOLUTION: The inspection tool includes: a centering member 2; and a branch member 3 mounted rotatably at the center of the centering member via a rotation shaft 4. The centering member 2 is provided with hooking parts 22 and 22' each protruding in parallel to the rotation shaft 4 at both ends of the centering member 2. Each of the hooking parts is attached to the centering member so that a holding part for fixing the centering member to the end portion of a tube P is movable forward and backward in a longitudinal direction of the centering member. Both ends of the centering member 2 and the end area of the branch member 3 have a mark which indicates a distance from the rotation shaft 4. With this, the rotation shaft 4 of the inspection tool 1 is positioned at the shaft center of the tube, and the branch member 3 rotates around the shaft center of the tube in a complete circle along the edge of the tube P. By checking the distance between the track of the mark given in the end area of the branch member 3 and the outer surface of the tube in a pipe diameter direction, a strain on the tube is checked on the entire periphery of the tube.

Description

  The present invention relates to a tube deformation inspection tool, and more particularly to an inspection device for confirming a strain state of an end portion of a tube.

  As shown in FIG. 5, cast iron pipes used for water pipes, etc., have a cylindrical straight part P1 having a uniform outer diameter and extending straight, a receiving part P2 provided at one end thereof and having an expanded outer diameter, and the like. It is mainly comprised from the insertion port part P3 provided in the end. And as shown in this figure, joining of cast iron pipes is performed by inserting the insertion port part P3 of another pipe inside the receiving port part P2.

  By the way, a large-diameter tube having a large diameter and a thin-walled tube having a small thickness are easily deformed, and even if no external force is applied, distortion may occur only by its own weight.

  In the case of a joint type that inserts the insertion port into the receiving port like a cast iron pipe and connects the tubes to each other, the tube is distorted, and a portion with a large outer diameter is formed at the insertion port, or the inner diameter at the receiving port. If a small part is made, it cannot be inserted into the receiving part and cannot be joined.

  For this reason, conventionally, the pipe ends are inspected to check the distortion before being brought into the pipe joining construction site, and if there is a distortion that seems to hinder the joining, it has been corrected in advance.

  The inspection is to check the presence or absence and degree of distortion by measuring the outer diameter at several locations in the circumferential direction of the end of the tube, and the measurement is usually performed using a tape measure or a straight scale.

  As another inspection method, a method in which an inner diameter measuring device is used to check the deformation of a pipe is disclosed (for example, see Patent Document 1). This is because the inner diameter measuring device with a measuring bar is installed in a steel pipe, the measuring bar is swung around the axis of the pipe, the inner diameter (radius) is measured at several locations in the circumferential direction, and the deformation state of the pipe is confirmed. To do.

  As described above, as a method of inspecting the deformation of the pipe, a method of directly measuring the outer diameter dimension or the like at the end of the pipe using a tape measure or a straight scale, or a high accuracy of the inner diameter dimension of the pipe using a measuring device. A method of measuring is conventionally known.

JP 07-43103 A

However, even if the outer diameter is measured at several locations in the circumferential direction at the end of the tube using a tape measure or straight scale, it does not measure over the entire circumference, so there is a risk of overlooking distorted distortion and local swelling. was there.
Further, when the above-described inner diameter measuring device is used with a large-diameter pipe, the weight increases due to the increase in the size of the apparatus, so carrying and mounting in the pipe are heavy work.
In addition, distortion is a problem when joining cast iron pipes, mainly because of the insertion section where the pipe thickness is thin. Therefore, it is necessary to simplify the inspection of the outer diameter of the insertion section. There has been a demand for an apparatus that can easily inspect distortion of the outer diameter over the entire circumference of the pipe, not the inner diameter measurement performed by an apparatus.

  An object of the present invention is to provide an inspection tool that has a simple structure and is light and can easily check the distortion of a tube.

In order to solve the above problems, an inspection tool of the present invention is a deformation inspection tool for a pipe that is attached to an end of a pipe to check the distortion of the pipe, and includes a centering member that is longer than the outer diameter of the pipe, and a core. And a branch member attached to the center side of the centering member so as to be pivotable via a rotating shaft. Both the distance from the rotating shaft to both ends in the longitudinal direction of the centering member and the turning radius of the tip of the branching member are It is longer than the radius of the centering member, and on both ends of the centering member, there are provided a pair of hanging portions that protrude opposite to the attachment position of the branch member, and each of the hanging portions is in contact with the tube. A gripping piece for fixing the centering member to the end of the tube is attached so as to be able to advance and retreat in the longitudinal direction of the centering member. It was set as the structure to attach.
With this configuration, the centering member can first be attached to the end of the tube so as to intersect the axial center of the tube by sandwiching the tube in a radial direction with a pair of gripping pieces, and then both ends of the centering member The center of the centering member (rotating shaft) can be aligned with the axis of the tube by moving the gripping piece forward and backward so that the radial distance between each mark provided on the side and the end of the tube is equal. If the branch member is turned around the rotation axis in this state, the mark at the tip of the branch member moves along the pipe end so as to draw a perfect circle around the axis of the pipe. By checking the distance (distance) in the tube radial direction from the end, distortion can be inspected over the entire circumference of the end of the tube.

Further, as the mark, a ruler can be attached to either or both of the centering member and the branch member along the longitudinal direction thereof.
By attaching a ruler as a mark to display the distance from the rotation axis in this way, the radial distance between the rotation axis and the pipe end can be confirmed accurately by reading the scale. If the mark is a ruler, the centering center (rotation axis) of the centering member can be accurately aligned with the axis of the tube, and if the marker at the tip of the branch member is a ruler, the entire circumference of the end of the tube The work of measuring the distortion amount can be performed more accurately.

Furthermore, the joint part which bends the front end side of a branch member can be provided in the middle of the longitudinal direction of the said branch member.
Thereby, when the front-end | tip of the branch member in turning interferes with the both end sides of a centering member, a branch member can be bent from a joint part and swiveled, and the both end sides of a centering member can be dodged. This allows the strain to be inspected all around the circumference of the tube, except for the interfering portion.

In addition, a fastener for fixing and releasing the joint can be attached to the joint.
Thereby, fixation and cancellation | release of a joint part can be performed easily.

  The tube deformation inspection tool of the present invention has a simple and light structure, and if this is used, the deformation (distortion) of the tube can be easily inspected over the entire circumference of the tube end. Never overlook distorted distortions or local bulges.

It is a front view which shows the use condition which mounted | wore the pipe | tube with the pipe deformation inspection tool based on this invention. It is an AA arrow top view of FIG. 1, (a) is the whole figure, (b) is an enlarged view of the centering member edge part. It is explanatory drawing of the branch member of the tube deformation | transformation inspection tool which concerns on this invention, (a) is the whole figure, (b) is the principal part enlarged view of C arrow, (c) is D arrow sectional drawing. It is explanatory drawing of the branch member which concerns on other embodiment of this invention. It is explanatory drawing of a cast iron pipe.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. Components common to the background art described above are assigned the same reference numerals and redundant description is omitted.

FIG. 1 is a front view showing a use state in which a tube deformation inspection tool according to the present invention is mounted on an insertion port end of a large-diameter tube.
As shown in the figure, the tube deformation inspection tool 1 is mainly composed of a centering member 2 and a branch member 3.
The centering member 2 intersects the axial center line of the pipe P, and is attached to the end of the pipe so that the longitudinal direction thereof is aligned with the radial direction of the pipe. A branch member 3 is attached to the center of the centering member 2 in the longitudinal direction via a rotating shaft 4 so as to be rotatable around the rotating shaft 4. The branch member 3 is divided into an arm part 31 on the rotating shaft 4 side and a gauge part 32 on the turning tip side, and the arm part 31 and the gauge part 32 are connected via a joint part 33.
Here, the rotating shaft 4 is aligned with the axis of the tube P, and both ends of the centering member 2 and the turning tip of the branch member 3 protrude outward from the outer surface of the tube P.
In addition, the branch member 3 has a rectangular bar shape when viewed from the front, and the centering member 2 has a shape in which a pair of slats 23 and 23 'for supporting the branch member 3 during turning are attached to both sides of the center of the rectangular bar body. doing.

2 is a plan view taken along the line AA in FIG.
The centering member 2 includes a rod-shaped casing portion 21 having a rectangular section that extends straight, a pair of hook portions 22 and 22 ′ that are bent at right angles in the same direction at both ends of the casing portion, and are opposed to each other. The slats 23, 23 'projecting from the side surfaces are provided.
Screw holes 221 and 221 ′ that pass through the hook portions 22 and 22 ′ in parallel with the longitudinal direction of the housing portion 21 are formed. An adjusting screw 11 is screwed into both screw holes, and a head 111 provided at one end of the adjusting screw protrudes outside the pair of hanging portions 22 and 22 ′ and is attached to the other end of the adjusting screw 11. The grip piece 5 protrudes inside the pair of hanging portions 22 and 22 '.

Both the housing part 21 and the hanging parts 22 and 22 'are made of metal, and the gripping piece 5 is made of resin. When the head 111 of the adjustment screw is turned by hand, the gripping piece 5 attached to the tip of the screw moves to one side in the screw axis direction, and when the screw is turned in the opposite direction, it moves to the other side.
Since the axial direction of the screw is parallel to the longitudinal direction of the housing part 21, the gripping piece 5 provided on one hanging part 22 can be advanced and retracted toward the other hanging part 22 'by turning the adjusting screw 11. It has become.

Further, at the center of the longitudinal direction of the housing part 21, the round bar is rotated in the direction opposite to the bending direction of the hanging parts 22, 22 ', that is, in the direction perpendicular to the longitudinal direction of the housing part and away from the pipe P. A shaft 4 is protruded.
Then, on the side surfaces near both ends of the casing portion 21, straight scales 6 and 6 ′ (scale) are attached along the longitudinal direction. The straight scales 6 and 6 ′ are each attached at a position separated from the axis of the rotary shaft 4 by an equal distance L1. By reading the scales of the straight scales 6 and 6 ′ pointed to by the end (outer surface) of the tube P, the relative position between the tube P and the centering member 2 (rotating shaft 4) can be confirmed.

  The branch member 3 is also a rod-shaped metal member having a rectangular cross section, and the aforementioned rotating shaft 4 is inserted into a round shaft hole 35 formed at one end thereof. The nut 41 is screwed onto the tip end side of the rotating shaft 4 and is prevented from coming off, and the branch member 3 can be turned around the shaft hole 35 (the rotating shaft 4) like a watch hand.

3A and 3B are explanatory views of the branch member, in which FIG. 3A is an overall view as seen from an arrow B in FIG. 1, FIG. 3B is an enlarged view of a main part as seen from an arrow C, and FIG. .
As shown in FIG. 3A, the arm portion 31 and the middle of the branch member 3 can be bent so that the distal end side of the branch member 3 can be bent away from the tube P (in the direction of arrow T in the figure). Two members of the gauge portion 32 are connected via a hinge 8 to constitute a joint portion 33. Fasteners 9 are attached to both side surfaces of the joint portion 33 to prevent it from being bent.
The stopper 9 includes a hook 94, a trigger 91, and a hook 93 that connect one ends of the two coil springs 92. The coil spring 92 can turn around the other end connected to the trigger 91, and the trigger 91 is attached to the arm portion 31 so as to freely turn. The hook 93 is fixed to the gauge portion 32. After the hook 94 is hooked on the hook 93, when the trigger 91 is pulled back in the direction away from the hook 93, the trigger stops with the coil spring 92 being pulled, and the hinge portion (joint portion) is fixed by the pulling force of the coil spring. It has become.

As shown in FIGS. 3A and 3B, the insert 10 is attached to the tip of the branch member 3. The insert 10 is formed by bending a thin steel plate with a narrow width at right angles to the thickness direction so as to form an L-shape. The bent tip is parallel to the axial direction of the rotary shaft 4 toward the tube P side, that is, It is attached to the tip of the branch member 3 so as to be opposite to the projecting direction of the rotating shaft 4. In the present embodiment, the bent tip of the insert 10 serves as a mark.
As shown in FIG. 3B, a long hole 101 is formed in the insert 10 so that it can be screwed to the tip of the branch member 3 while adjusting the attachment position.
In order to confirm the dimension L3 from the core of the shaft hole 35 (swivel center) to the tip of the insert (mark), the tip of the branch member has the insert 10 having a length L4 at a position away from the center of rotation by a certain distance L2. A straight scale 7 (scale) is attached so as to be arranged horizontally.

  A pair of guide portions 34, 34 ′ that face the end surface of the pipe P when the branch member is turned are projected from the centering member side, that is, the surface of the pipe P at the tip of the branch member. The insert 10 is attached between the pair of guide portions 34, 34 ′, and the tip thereof protrudes from the tip of the gauge portion 32.

  Next, a method for confirming the presence / absence of deformation (distortion) of the outer diameter over the entire circumference of the pipe end using this pipe deformation inspection tool will be described.

  First, the housing portion 21 of the centering member 2 is applied to the end portion of the tube P from the side of the hanging portions 22 and 22 ′. At this time, the positioning is performed so that the gripping pieces 5 and 5 ′ of the hanging portion are on the outside of the outer surface of the pipe and the rotation shaft 4 of the centering member 2 is close to the axis of the pipe P.

  Next, the centering member 2 is moved in the longitudinal direction until the gripping piece 5 of one of the hanging portions 22 hits the outer surface of the pipe P. When one gripping piece 5 comes into contact with the outer surface of the tube P, the centering member 2 is slowly swung along the end surface of the tube P with the gripping piece 5 as a fulcrum, and the other gripping piece 5 ' Find the angle (positional relationship) closest to the outer surface of the tube.

At that angle (positional relationship), the adjustment screw 11 ′ of the other gripping piece 5 ′ is tightened, and the pipe P is sandwiched in the radial direction by the gripping pieces 5, 5 ′.
Next, looking at the straight scales 6 and 6 ′, the scales pointed to by the outer surface of the pipe P, that is, the scales of the intersections of the straight scales 6 and 6 ′ and the outer surface of the pipe P are read, and both scales are equal. In such a manner, the adjusting screws 11 and 11 ′ are turned to insert and remove the gripping pieces 5 and 5 ′. If the scales are equal, the tube deformation inspection tool 1 is attached to the end surface of the tube P in a state where the rotation shaft 4 of the centering member 2 is aligned with the axis of the tube P, that is, in a state where the centering is completed. It will be.

  Subsequently, the radial gap between the tip (mark) of the insert 10 attached to the branch member 3 and the outer surface of the pipe P is confirmed. The clearance is confirmed over the entire circumference of the pipe P while turning the branch member 3 around the rotation shaft 4. Here, the insert 10 is attached to the branch member 3 so that the distance L3 between the tip (mark) and the axis of the rotary shaft 4 is half of the allowable maximum value of the outer diameter of the pipe P.

  As the branch member is swung, the tip of the insert 10 and the guide portions 34 and 34 'hit the hooking portions 22 and 22' and the gripping pieces 5 and 5 'of the centering member and interfere with each other. At this time, the fasteners 9 attached to both side surfaces of the branch member 3 are removed, the joint portion 33 is unfixed, and the gauge portion 32 is bent away from the tube P (see arrow T in FIG. 3A). In this state, when the gauge portion 32 continues to turn and passes the hook portion, the bent branch member is returned and extended, and the joint portion 33 is locked again using the stopper 9.

  After fixing the joint portion 33, the branch member 3 is turned again, and the radial gap between the tip (mark) of the insert 10 and the outer surface of the pipe P is continuously checked. If there is no gap or a spot where the tip of the insert (mark) contacts the outer surface of the tube is found, distortion that affects the joining work has occurred, so correction work is performed to eliminate the distortion.

In this embodiment, a straight scale is attached to both ends of the centering member and used to check the distance from the turning center (rotating shaft). However, without attaching a straight scale, the distance from the turning center is a mark. A mark display may be written or a protrusion or groove serving as a mark may be provided.
In the present embodiment, the insert 10 is attached to the tip of the branch member as a mark. However, as shown in FIG. 4, a straight scale 7 'may be attached instead of the insert. In that case, distortion of the outer diameter can be confirmed by reading the scale of the intersection of the straight scale 7 'and the outer surface of the pipe over the entire circumference of the pipe while turning the branch member.

  Furthermore, in the present embodiment, the casing part and the hanging part and the branch member of the centering member are made of metal, but not limited to metal, any material that can secure the rigidity of each member can be used. For example, it can be made of resin or wood. Similarly, the grip piece is not limited to resin, but may be any material that does not slip when the pipe P is gripped and does not damage the pipe, and may be made of metal or wood.

1 Tube deformation inspection tool
2 Centering member 3 Branch member 4 Rotating shaft 5, 5 'Holding piece 6, 6' Straight scale (measurement / mark)
7 Straight Scale 7 'Straight Scale (Measurement / Mark)
8 Hinges 9 Fasteners 10 Fee (mark)
11 Adjustment screw 22, 22 'Hanging part 33 Joint part 101 Long hole P Cast iron pipe (pipe)

Claims (4)

A tube deformation inspection tool that is attached to the end of a tube to check the distortion of the tube,
A centering member that is longer than the outer diameter of the tube, and a branch member that is pivotally attached to the center side of the centering member via a rotating shaft,
Each distance from the rotation axis to both ends in the longitudinal direction of the centering member and the turning radius of the tip of the branch member are both longer than the radius of the pipe outer surface,
On both ends of the centering member, there are provided a pair of opposing hooks protruding opposite to the attachment position of the branch member, and in each hook, the centering member is brought into contact with the pipe at the end of the pipe. Attach the gripping piece to be fixed so that it can advance and retreat in the longitudinal direction of the centering member.
A tube deformation inspection tool, characterized in that marks indicating the distance from the rotation axis are attached to both ends of the centering member and the tip of the branch member.   2. The tube deformation inspection tool according to claim 1, wherein a ruler is attached to one or both of the centering member and the branch member along the longitudinal direction as the mark.   3. The tube deformation inspection tool according to claim 1, wherein a joint portion that bends the distal end side of the branch member is provided midway in the longitudinal direction of the branch member.   The tube deformation inspection tool according to claim 3, wherein a stopper for fixing and releasing the joint is attached to the joint.

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