JP2004108036A - Contraction allowance measuring device of pipe joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To measure a contraction allowance formed in the joint of an aseismatic pipe from the outside in an aseismatic pipeline such as city water, gas, and sewer. <P>SOLUTION: The device is provided with an external pipe and internal pipe slidably inserted in the external pipe. Bill-shaped measuring terminals protruding in the right angled direction against the axial direction are provided at front ends of the internal and external pipes. Graduations by which the relative shift distance of the internal pipe to the external pipe can be measured are made at rear ends of the internal and external pipes. It is preferable that a supporting element with a caster rotatably supporting the external and internal pipes around the axis is provided. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a shrinkage allowance measuring device that can externally measure a shrinkage allowance provided in a joint portion of an earthquake-resistant pipe in a water pipe, a gas, a sewer, or the like laid with the earthquake-resistant pipe. .
[0002]
[Prior art]
BACKGROUND ART Some ductile cast iron pipes and the like used for water pipes and the like are provided with earthquake-resistant pipe joints that can expand and contract when a large force due to an earthquake or the like acts on the pipes after the pipes are buried and absorb the external force. In order to secure the expansion and contraction function of this type of pipe having earthquake resistance, when a pipe is laid underground, a shrinkage allowance, which is referred to as a trunk gap, must be left at the joint between the front and rear pipes.
[0003]
When laying this kind of pipe, a propulsion method is often adopted in which a fume pipe or the like is used as a sheath pipe and the pipe is spliced inside the pipe. When a pipe is laid by this propulsion method, a thrust (force at the time of inserting the pipe) is transmitted from a succeeding pipe to a preceding pipe. If NS-type pipe joints (same as S-type pipe joints and other seismic joints) are used, and if no means for maintaining the spacing is taken, the insertion port at the tip end as shown by the dotted line in the figure. The front end face Pb of the insertion port on which the projection is formed is pushed into the deep end Pa of the receiving port, and there is no margin for pushing (shrinkage allowance, body spacing) L, and the joint needs to expand and contract in both directions. There is a problem that the performance as a certain seismic pipe P is not provided.
[0004]
During propulsion of seismic pipes, crushed by its own inflation pressure after embedding inside an exterior frame having a pair of front and rear annular plates fixed to each other facing each other at a predetermined interval to secure the shrinkage allowance of the pipe joint (Japanese Patent Application Laid-Open No. 2000-282779) A method in which an annular brittle molded body is sandwiched, and after the propulsion is completed, the pipe is propelled using a propulsion force transmitting collar that allows the two annular plates to approach each other by crushing the brittle molded body. In addition, a method has been developed in which a spacer that can be removed by an external operation after completion of propulsion is interposed in a joint portion and propulsion is performed with a contraction allowance secured. According to these methods, the propulsive force can be transmitted efficiently, and the joint can be contracted after the propulsion is completed.
[0005]
[Problems to be solved by the invention]
By the way, in this type of seismic pipe propulsion method, there is a case where it is checked whether a contraction allowance of a joint portion of a laid pipe is secured to a specified amount. Conventional methods for measuring the shrinkage allowance include a method in which an operator directly enters the pipe and measures the spacing with a torso with calipers, a method in which a camera is inserted into the pipe and analysis and measurement is performed on a television image, This is a method of measuring the position of a mark (white line or the like) displayed on the outer periphery and calculating the body spacing.
[0006]
However, the method in which the worker directly enters the pipe to perform the measurement has a problem that the pipe inner surface is soiled by a foot or the like, the inner surface protection material is damaged, and there is also a risk of an accident due to lack of oxygen. In addition, the method of measuring by inserting a camera into a tube requires expensive equipment, requires a skill in the measurement, and requires a long working time. Further, the method of measuring with a mark displayed on the outer periphery of the pipe cannot be measured by a method of inserting an earthquake-resistant pipe into the sheath because the mark cannot be seen. Accordingly, an object of the present invention is to provide a simple measuring device that can relatively easily measure the trunk interval from outside even when a person cannot enter the pipe.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, the present invention employs the following configuration. That is, the pipe joint shrinkage allowance measuring apparatus according to the present invention is a measuring apparatus for measuring a shrinkage allowance of a pipe joint part in a water pipe or the like buried underground by propelling a plurality of pipes while joining the pipes. A pipe, comprising an inner pipe slidably inserted into the outer pipe, and a beak-shaped measuring terminal projecting in a direction perpendicular to the axial direction is provided at a tip portion of each of the outer pipe and the inner pipe, A scale is provided at the rear end of the outer tube and the inner tube so as to measure a relative movement amount of the inner tube with respect to the outer tube.
[0008]
In this measuring device, a pair of measuring terminals provided on an outer tube and an inner tube are inserted into the tubes, and the measuring terminals are inserted into the front and rear end faces of the jointed body, that is, the front end face of the insertion port and the depth of the receiving port. Make contact with the end face. This operation can be easily performed by relatively moving the inner tube and the outer tube. When the pair of measuring terminals abut against the end face of the body spacing, the body spacing can be measured by reading the relative movement of the inner and outer tubes at that time on a scale.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described more specifically based on embodiments of the present invention shown in the drawings.
[0010]
FIG. 1 illustrates a method using this shrinkage allowance measuring device (abbreviated as "measuring device") 1. This measuring device 1 is a double tube of an outer tube 2 and an inner tube 3 inserted into the outer tube. It has a structure. A first measuring terminal 4 having a measuring surface 4a which is in contact with an end face on the receiving side of the seismic pipe (NS type seismic pipe in FIG. 1) P, that is, an inner end face Pa of the receiving port, is provided at the tip of the outer pipe 2 in the axial direction. It is fixed so as to protrude at right angles. Further, a second measuring terminal 5 having a measuring surface 5a that is in contact with the distal end surface Pb of the insertion port is fixed to the distal end of the inner tube 3. In the illustrated example, the inner pipe 3 is also made of a pipe and is lightweight, but in some cases, the inner pipe 3 may be made of a solid rod.
[0011]
The measuring terminals 4 and 5 have a plate shape with a wide base, and a thin measuring portion extends therefrom. The inner surfaces of the measuring terminals 4 and 5 facing each other are parallel, and the inner surfaces are in close contact with each other when the inner tube 3 is fully drawn into the outer tube 2. The outer surfaces of the measuring section are the measuring surfaces 4a and 5a. Since the inner end surface of the receptacle is a curved surface, it is preferable that the end of the measurement surface 4a that comes into contact with this surface be rounded (R) as shown in FIG.
[0012]
A plurality (usually two) of support members 10 are attached to an intermediate portion of the outer tube 2. The support 10 has a caster 12 attached to the lower surface of a cylindrical body 11 that fits over the outer tube 2. The measurement terminals 4 and 5 project below the lower surface of the caster 12. The outer tube 2 is rotatable with respect to the cylinder 11, and stoppers 13, 13 for regulating the axial movement of the support 10 are attached to the front and rear of the cylinder 11.
[0013]
Indicator protrusions 16 and 17 indicating the direction of the measurement terminal are attached to the rear ends of the outer tube 2 and the inner tube 3. Since the indicator projections 16 and 17 project in the same direction as the measurement terminals 4 and 5, the direction of the measurement terminal in the tube can be known from the outside of the sheath tube. The indicator projections 16 and 17 can be rotated in the circumferential direction of the outer tube to adjust the directions by loosening the fixing screws 18. This is to correct when the directions of the measurement terminals 4 and 5 change.
[0014]
At the rear end of the inner tube 3 protruding from the rear end of the outer tube 2, there is provided a scale 20 representing the amount of movement with respect to the outer tube 2. The scale 20 is pushed into the outer tube 2 when the distance between the measuring terminals 4 and 5 is increased by moving the inner tube 3 forward, but by reading the scale at the position of the rear end face of the outer tube 2. The distance between the measuring surfaces 4a and 5a of the two measuring terminals, that is, the shrinkage allowance can be measured. As shown in FIG. 2, the distance A between the measurement surfaces 4a and 5a in the closed state where the measurement terminals 4 and 5 are in close contact with each other, and the scale 20 on the rear end surface of the outer tube 2 in that state are aligned with A. In other words, since the read amount is directly used as the interval of the body of the joint portion, the measurement becomes easier.
[0015]
A connecting portion 30 is provided at an intermediate portion between the outer tube 2 and the inner tube 3. The structure of the connecting portion 30 is as follows. That is, in the case of the outer tube 2, the screw portion 2 c provided at the rear end of the front outer tube 2 (A) and the screw portion 2 d provided at the front end of the rear outer tube 2 (B) are shared by a common screw cylinder 31. Are joined by screwing from both sides. In the case of the inner pipe 3, a screw hole 3b is provided at the rear end of the front inner pipe 3 (A), and a screw screwed into the screw hole at the front end of the rear inner pipe 3 (B). A rod 3c is protruded and joined by screwing the screw rod 3c into the screw hole 3b.
[0016]
The outer pipe 2 and the inner pipe 3 can be extended by adding splicing pipes 32 and 33 as necessary, for example, when the length of the seismic pipe changes. FIG. 3 shows this refilling method, in which a connecting portion 30 provided at an intermediate portion between the outer pipe 2 and the inner pipe 3 is removed, and connecting pipes 32 and 33 are connected between the separated front and rear pipes. In the case of the outer tube 2, the threaded portion 32 a of the joint pipe 32 is screwed into the screw hole on the rear side of the screw tube 31, and another screw tube 31 is screwed on the threaded portion on the rear side of the joint tube 32. A separated rear outer tube 2 (B) is screwed into the other (rear) screw hole of the rear screw tube 31.
[0017]
In the case of the inner pipe 3, the rod 3c of the rear inner pipe 3 (B) is pulled out from the screw hole 3b of the front inner pipe 3 (A), and the rod 33c of the connecting pipe 33 is screwed. The rod 3c of the rear inner pipe 3 (B) is screwed into the screw hole 33b at the rear end of the connecting pipe 33. As described above, the lengths of the outer tube 2 and the inner tube 3 can be easily extended.
[0018]
A method for measuring the spacing of the pipes after propulsion using the measuring device 1 will be described. At the time of measurement, before inserting the measuring device 1 into the propelled pipe P, the inner pipe 3 is pulled into the outer pipe 2 until the measuring terminal 5 of the inner pipe 3 comes into contact with the measuring terminal 4 of the outer pipe 2. The measurement terminals 4 and 5 are closed, and the scale A in this state is read. Thereafter, the measuring device 1 is inserted into the pipe P from the rear end of the pipe. When inserting the measuring device 1 into the pipe, the outer terminals 2 and the inner tube 3 are rotated half an axis around the measuring terminals 4 and 5 so that the measuring terminals 4 and 5 do not rub the inner surface of the tube. Keep it. In addition, since the measuring device 1 is supported by the support 10 having casters, this insertion is easy.
[0019]
When the tip of the measuring device 1 reaches the joint J of the pipe (which can be easily known from the length of the tube and the length of the measuring device 1), the outer tube 2 and the inner tube 3 are rotated around the axis to measure. Terminals 4 and 5 face down. At this time, since the positions of the measuring terminals 4 and 5 are located at the interval of the fitting of the pipe joint, when the measuring terminal is turned downward, the tip of the measuring terminal is inserted into the interval of the fitting, that is, the back end face Pa of the receptacle. It fits between the front end face Pb of the mouth. In this state, when the outer cylinder 2 is pulled backward (FIG. 6), the measurement surface 4a of the measurement terminal 4 on the outer cylinder comes into contact with the inner end face Pa of the receptacle. Thereafter, the inner cylinder 3 is pushed forward to bring the measurement surface 5a of the measurement terminal 5 into contact with the front end surface Pb of the insertion port (FIG. 7). By reading the movement distance until the measurement surface 5a comes into contact with the front end surface of the insertion port with the scale 20, the body-to-body spacing L can be calculated. That is, the value obtained by adding the above-mentioned moving distance to the distance A between the two measurement surfaces 4a and 5a in a state where both the measurement terminals 4 and 5 are closed is the body-fitting interval (shrinkage allowance). It is only necessary that this value be equal to or longer than the specified length. According to the “Technical Standards for Seismic Joints for Underground Pipes and Pipes” (draft) of the National Land Development Technology Center, this body spacing, ie, shrinkage allowance, is 1% or more of the pipe length.
[0020]
In the illustrated example, since the indicator protrusions 16 and 17 are provided at the rear ends of the inner tube 3 and the outer tube 2, the operation can be performed while grasping the direction of the measuring terminal. In other words, when inserting or pulling out, the indicator protrusion can be directed upward so that the measuring terminal does not rub the inner surface of the tube. At the time of measurement, the tube is rotated and the indicator protrusions 16 and 17 are directed downward. Can be easily known. In addition, since the measuring terminal protrudes in the diameter direction of the tube, it is possible to prevent the inner tube 3 from getting into the outer tube 2 too much. When the measurement is completed, the measuring terminal 5 of the inner tube 3 and the measuring terminal 4 of the outer tube 2 are overlapped again, and the outer tube 2 and the inner tube 3 are rotated half a turn so that the measuring terminals 4 and 5 are turned upward. What is necessary is just to pull out 2 from the pipe together with the inner pipe 3.
[0021]
The measuring device 1 can measure the distance between the body and the outside of the pipe without entering the pipe after joining the joint. Since the insertion and the drawer are moved while rolling the casters, there is no possibility that the inner surface of the pipe is stained or damaged. In addition, since the indicator indicating the direction of the measuring terminal is provided at the rear end of the measuring device 1, the direction of the measuring terminal can be easily known outside the tube. Since the outer tube 2 and the inner tube 3 have a structure in which the front and rear divided tubes are connected at an intermediate portion thereof, when the length of the tube changes, the outer tube 2 and the inner tube 3 are connected to the outer tube 2 and the inner tube 3. The length of the pipe can be easily adjusted by adding the pipe.
[0022]
【The invention's effect】
As is clear from the above description, the shrinkage allowance measuring device for a pipe joint according to the present invention can easily measure the shrinkage allowance from outside without an operator entering a propelled water pipe or the like. Therefore, it has become possible to easily check whether or not the seismic pipe joints in the laid pipe have appropriate seismic resistance. Needless to say, this measuring device can be used for purposes other than the measurement of the shrinkage allowance of the earthquake-resistant pipe joint, for example, for measuring the length of a concave portion in a structure where no human can enter.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating a state in which a shrinkage allowance of a pipe joint is measured using the measuring device of the present invention.
FIG. 2 is a front view of the measuring device.
FIG. 3 is an explanatory diagram of a case where a connecting pipe is added to a connecting portion.
FIG. 4 is an enlarged view of a measurement terminal.
FIG. 5 is a cross-sectional view illustrating a state in which the measuring device is inserted into a pipe.
FIG. 6 is a cross-sectional view illustrating a state in which a measurement terminal faces downward.
FIG. 7 is an explanatory diagram of a measuring method.
FIG. 8 is an explanatory view of an NS type earthquake-resistant pipe joint.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Measuring device 2 Outer tube 3 Inner tube 4 Measuring terminal 5 Measuring terminal 10 Support 12 Caster 16 Indicating protrusion 17 Indicating protrusion 20 Scale 30 Connecting part

Claims (5)

A measuring device for measuring a shrinkage margin of a pipe joint portion in a water pipe or the like buried underground by propelling while joining a plurality of pipes, comprising an outer pipe and an inner pipe slidably inserted into the outer pipe. A beak-shaped measuring terminal is provided at the tip of each of the outer tube and the inner tube, which protrudes in a direction perpendicular to the axial direction. An apparatus for measuring a shrinkage allowance of a pipe joint portion, wherein a scale capable of measuring a relative movement amount of a pipe is provided. The shrinkage allowance measuring device for a pipe joint according to claim 1, wherein the inner pipe and the outer pipe are supported by a support provided with casters so as to be rotatable about an axis. The shrinkage allowance measuring device for a pipe joint according to claim 1 or 2, wherein the inner pipe and the outer pipe are configured to be adjustable in length by joining different joint pipes. The shrinkage allowance measuring device for a pipe joint according to any one of claims 1 to 3, wherein a rounded portion corresponding to a curved surface of a receiving end surface of the pipe joint is formed on an outer surface of a distal end portion of the measurement terminal. The shrinkage allowance measuring device for a pipe joint according to any one of claims 1 to 4, wherein indicator protrusions are provided at rear end portions of the inner pipe and the outer pipe in the same direction as the protruding direction of the measurement terminal.

Images