JP2011191240A - Strain-measurement device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately measure the state of a strain of a surface of a plate member, having an outer circular edge which is used to form a flange potion of a pipe, etc. <P>SOLUTION: A strain measuring device 101 includes a plurality of long supporting arms 102. Each supporting arm has its end supported by a base 103 and extends radially within a plane parallel to a surface to be measured 201a. Each surface to be measured 201a is provided with a holding section 104, that holds an edge portion of the surface to be measured 201a. A measuring arm 105 extends in parallel with the surface to be measured 201a and expands and contracts freely along its length. A dial gauge 106, provided on the measuring arm 105, measures the strain of the surface to be measured. A coupling section 107 couples the base 103 and the measuring arm 105 with each other so that the dial gauge 106 becomes free to rotate within a plane parallel to the surface to be measured 201a. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a strain measuring device for measuring the surface strain of a plate-like member that is used in a flange portion or the like provided at an end of a pipe and whose outer edge is circular.

  Conventionally, in pipes such as turbines, boilers, and reactors that have been introduced into power plants and chemical plants, flanges are formed at the ends, and the sheet surfaces of the flanges are brought into contact with each other to connect the pipes together. To be done.

  The seat surface of the flange portion may be distorted due to a tightening force applied by bolts when the pipe is connected, heating, corrosion or deterioration due to aging. For this reason, it is important to periodically repair the sheet surface to prevent leakage from between the sheet surfaces at the connection point of the piping. And when repairing the sheet | seat surface of a flange part, measuring the distortion | strain of a sheet | seat surface using the distortion | strain measuring apparatus as described in patent document 1 or a nonpatent literature 1 is performed. In this strain measuring apparatus, the support column 1 forms the center of rotation of a measuring shaft 26 having a dial gauge 25 attached to the tip.

Japanese Patent No. 3767588 (paragraphs 0005 to 0006, FIGS. 1 and 4)

Satoshi Kirihara, “Special Feature Axial Force Measurement, Leakage Prevention Technology from Flange Joint”, page 14, right column, line 19 to page 15, right column, line 10, [online], October 2003, Shinsei Plantech Co., Ltd. Web In the site, [Search February 22, 2010], Internet <URL: http://www.s-plantech.co.jp/technical/pdf/0310_rosetubosi.pdf>

  However, even if the strain measuring device described in Patent Document 1 or Non-Patent Document 1 is attached to the flange F, the support is not supported by play of the main link 4 or the sub link 6 and play on the pins 5, 7, 8, and 9. 1 is not necessarily stable by extending in a direction perpendicular to the surface formed by the flange F. For this reason, using the strain measuring device described in Patent Document 1 or Non-Patent Document 1, the distortion of the surface of the plate-like member used in a flange portion or the like provided at the end of the pipe is formed in a circular shape. When trying to measure, the measurement result changes every time measurement is performed.

  The present invention has been made in view of the above points, and an object of the present invention is to accurately measure the state of distortion of the surface of a plate-like member whose outer edge is circular.

  The strain measurement device of the present invention is a strain measurement device that measures strain on a measurement target surface having an outer edge formed in a circular shape, and includes a plurality of long support arms and the measurement by holding each of the support arms. A base that extends radially in a plane parallel to the target surface, a holding portion that is provided on the support arm and holds an edge portion of the measurement target surface, extends parallel to the measurement target surface, and is in the length direction A measuring arm that is freely extendable and retractable, a measuring unit that is provided on the measuring arm and that measures the distortion of the measurement target surface, and the measurement unit is rotatable in a plane parallel to the measurement target surface. A connecting portion that connects the base and the measurement arm.

  According to the present invention, when the holding portion holds the edge portion of the measurement target surface, the base portion is positioned at the circular center of the measurement target surface, and the measurement portion is rotated along with the rotation of the measurement arm around the base portion. Rotates in a plane parallel to the surface to be measured, so that the state of distortion of the surface of the plate-like member whose outer edge is circular can be accurately measured.

It is a top view of a distortion measuring device. FIG. 2 is a cross-sectional view taken along line AA in FIG. 1. It is a top view of a base. It is front sectional drawing of a connection part.

  One embodiment will be described with reference to FIGS. 1 to 4. In the present embodiment, one surface of a ring-shaped metal disc 201 constituting a flange portion provided at an end of a pipe of a turbine, boiler, reactor or the like introduced in a power plant or chemical plant (measurement object) This is an application example to the strain measuring apparatus 101 for measuring the strain of the surface 201a).

  FIG. 1 is a plan view of the strain measuring apparatus 101. The strain measuring apparatus 101 includes a supporting arm 102, a base 103, a holding unit 104, a measuring arm 105, a dial gauge 106 as a measuring unit, and a connecting unit 107 (see also FIGS. 2 and 4). Including. The measuring device 101 is attached to a metal disk 201 that is arranged in advance horizontally and measures the distortion of the measurement target surface 201 a of the metal disk 201.

  The support arm 102 is a long member, and is formed of aluminum metal as an example, so that the weight of the entire measuring apparatus 101 is reduced. The cross-sectional shape of the support arm 102 is substantially square. Four supporting arms 102 are provided in the measuring apparatus 101, each extending in parallel with the measurement target surface 201a, and as shown in FIG. 1, centering on a base 103 (details will be described later based on FIG. 3). Arranged at intervals of 90 degrees in the circumferential direction.

  FIG. 2 is a cross-sectional view taken along line AA in FIG. The holding unit 104 will be described with reference to FIGS. 1 and 2. The holding unit 104 is provided at the end of each supporting arm 102 opposite to the base 103 and holds the edge portion of the measurement target surface 201a. Each of the holding portions 104 includes a columnar member 151, an upper fixing portion 152, an adapter portion 153, a lower surface pressing portion 154, and an upper surface pressing portion 154a.

  The columnar member 151 is a prismatic body extending in the vertical direction. A through hole (not shown) penetrating in the horizontal direction is formed in an upper portion of the columnar member 151. The upper fixing portion 152 fixes the support arm 102 inserted through the through hole to the columnar member 151.

  An adapter part 153 is attached to the lower end of the upper fixing part 152. The adapter unit 153 has a base plate 155. The base plate 155 extends horizontally and contacts the lower surface of the columnar member 151. A standing plate 156 is erected above the base plate 155. The standing plate 156 faces the side surface of the columnar member 151. The adapter part 153 also has a lower fixing part 158. The lower fixing portion 158 has a cushion material 157 and sandwiches the columnar member 151 together with the standing plate 156. Further, the first rack gear 160 hangs down from the lower surface of the base plate 155. The first rack gear 160 has a tooth portion 159 facing the inside of the metal disc 201. A lower piece 161 extends from the lower end of the first rack gear 160 toward the inside of the metal disc 201. The lower piece 161 is formed with a female screw hole (not shown) penetrating vertically.

  The lower surface pressing portion 154 has a shaft 162. A male screw portion (not shown) that is screwed into the female screw hole of the lower piece 161 is formed in the middle of the shaft 162. A handle 163 is provided at the lower end of the shaft 162. A contact body 164 that contacts the lower surface 201 b of the metal disc 201 is provided at the upper end of the shaft 162.

  The upper surface pressing portion 154 a has a plate material 165. The lower surface of the plate material 165 is in contact with the measurement target surface 201a. A cushion material 166 is provided on the upper surface of the plate material 165. A second rack gear 167 that meshes with a tooth portion 159 of the first rack gear 160 extends vertically from an edge of the plate member 165 facing the outside of the metal disc 201.

  The operator moves the columnar member 151 in the vertical direction with respect to the support arm 102 and in the length direction of the support arm 102. Subsequently, the worker fixes the support arm 102 and the columnar member 151 by the upper fixing portion 152. The operator attaches the adapter portion 153 to the columnar member 151 by the lower fixing portion 158. Subsequently, the operator brings the cushion material 166 into contact with the lower surface of the base plate 155, engages the second rack gear 167 with the first rack gear 160, sandwiches the metal disc 201 between the plate material 165 and the contact body 164, and handles 163. To move the contact body 164 against the lower surface 201b of the metal disc 201. By doing in this way, each holding part 104 pinches | interposes the metal disc 201 from the outer side, and hold | maintains the edge part of the measurement object surface 201a.

  FIG. 3 is a plan view of the base 103. Based on FIG.2 and FIG.3, the base 103 is demonstrated. The base 103 holds the ends of the respective support arms 102 and extends these support arms 102 radially in a plane parallel to the measurement target surface 201a. The base 103 includes a first foundation pillar 171, a case body 172, a second foundation pillar 173, an arm connecting member 174, and a bolt 174 a.

  The case body 172 includes three plate-like members 175a, 175b, and 175c that are spaced apart from each other and arranged vertically. The first basic pillar 171 is a cylindrical body extending vertically, and connects the center of the upper plate member 175a and the center of the intermediate plate member 175b. The corner region of the upper plate member 175a and the corner region of the intermediate plate member 175b are connected by four column members 176. The ends of the support arms 102 enter the upper space 177 between the upper plate member 175a and the intermediate plate member 175b. The end surface of the support arm 102 is in contact with the side surface of the first foundation pillar 171.

  The arm connecting member 174 is a plate-like member that is bent in a substantially L shape in plan view. The arm connecting member 174 is disposed across the side surface in the vicinity of the end of the adjacent support arm 102. The bolt 174 a fastens the end of the arm connecting member 174 and the side surface of the support arm 102. Then, by using two bolts 174a for one arm connecting member 174, the arm connecting member 174 connects adjacent supporting arms 102, and each supporting arm 102 is connected in a plane parallel to the measurement target surface 201a. 1 The base pillar body 171 is extended radially.

  The second foundation pillar 173 is a cylindrical body that extends vertically so as to coincide with the axis AX of the first foundation pillar 171 and connects the center of the intermediate plate member 175b and the center of the lower plate member 175c. The corner region of the intermediate plate member 175 b and the corner region of the lower plate member 175 c are connected by four column members 178. A connecting portion 107 is provided in a lower space 179 between the intermediate plate member 175b and the lower plate member 175c.

  Please refer to FIG. 1 and FIG. An arm bracket 180 is disposed below the case body 172. The arm bracket 180 has two protruding pieces 180a and a connecting piece 180b for connecting them, and has a U-shape that is opened downward. The connecting piece 180b has a flat plate shape extending in parallel with the measurement target surface 201a. The two protruding pieces 180a are parallel to each other, and both form a flat plate shape orthogonal to the connecting piece 180b.

  The measurement arm 105 is held by the two protruding pieces 180a of the arm bracket 180 and extends in parallel with the measurement target surface. The measuring arm 105 includes three slide units 181 that can be expanded and contracted in the length direction. Each slide unit 181 includes a large-diameter pipe 181a, a small-diameter pipe 181b that is slidably inserted therein, and a fixing lever 181c that fixes the small-diameter pipe 181b to the large-diameter pipe 181a. Such slide units 181 are arranged in parallel to each other so as to be located at the apex of the triangle when viewed from the cross-sectional direction, one above and two below. Here, the two protruding pieces 180a respectively hold one end and the middle part of each large-diameter pipe 181a, and extend the large-diameter pipe 181a outward from the one protruding piece 180a. The other end of each large-diameter pipe 181 a is connected by a plate member 182. The distal ends of the small diameter pipes 181b are connected by a plate member 183.

  The dial gauge 106 measures the distortion of the measurement target surface 201 a and is attached to a plate member 183 located at the distal end portion of the measurement arm 105. The dial gauge 106 has a probe 184 that extends downward. The tip of the probe 184 contacts the measurement target surface 201a of the metal disc 201. Then, the tip of the measuring element 184 rotates around the axis AX of the first basic pillar body 171 in accordance with the rotational movement of the measuring arm 105 (described later based on FIGS. 2 and 4), and the measurement target surface 201a. Slide. The dial gauge 106 outputs a detection value corresponding to the size of the unevenness of the measurement target surface 201a based on the vibration of the probe 184 caused by the sliding.

  FIG. 4 is a front sectional view of the connecting portion 107. Based on FIG.2 and FIG.4, the connection part 107 is demonstrated. The connecting portion 107 connects the base portion 103 and the measuring arm 105 so that the dial gauge 106 is rotatable in a plane parallel to the measurement target surface 201a. The connecting portion 107 includes a gear 185, a rotating column 186, a radial bearing 187, a thrust bearing 188, and a load receiving member 189.

  A radial bearing 187 is attached to the second base pillar 173 extending downward from the lower surface of the plate-like member 175b. On the outer periphery of the radial bearing 187, a gear 185 is provided in the direction around the axis of the second basic pillar body 173. A rotating column 186 extends downward from the gear 185 so as to coincide with the axis AX. The rotating column 186 enters the hole 190 formed at the center of the plate-like member 175 c and is connected to the center of the upper surface of the connecting piece 180 b of the arm bracket 180.

  The load receiving member 189 is attached to the lower surface of the plate-like member 175c. A through hole 191 is formed in the load receiving member 189 along the axis AX. The rotating column 186 enters the through hole 191.

  The thrust bearing 188 is positioned in the hole 190, is placed on the upper surface of the load receiving member 189, and supports the rotating column 186 so as to be rotatable about its axis.

  Incidentally, a worm gear 192 is engaged with the gear 185. The worm gear 192 is supported on the case body 172 by a support member (not shown) so as to be rotatable about its axis. The worm gear 192 extends in the horizontal direction and extends from the lower space 179 to the outside of the case body 172. At the tip of the worm gear 192, a handle 193 is provided for an operator to turn the worm gear 192 around its axis.

  Using the measuring apparatus 101 according to the present embodiment configured as described above, the operator can set the edge of the measurement target surface 201a of the metal disc 201 arranged in the holding unit 104 so as to be horizontally oriented in advance. Hold the part. Here, the supporting arms 102 extend radially from the base 103 in a plane parallel to the measurement target surface 201a at intervals of 90 degrees. For this reason, if each holding | maintenance part 104 hold | maintains the edge part of the measurement object surface 201a, the base 103 will be located in the circular center position which the metal disc 201 forms.

  Subsequently, the operator moves the fixing lever 181c to expand and contract the measurement arm 105, positions the dial gauge 106 above the measurement target surface 201a, and brings the tip of the measuring element 184 into contact with the measurement target surface 201a.

  Subsequently, the operator moves the handle 193 and rotates the worm gear 192 around its axis. As a result, the gear 185 rotates in the direction around the axis AX, and accordingly, the tip of the measuring element 184 slides in the circumferential direction of the metal disc 201 in contact with the measurement target surface 201a. The dial gauge 106 outputs a detection value corresponding to the size of the unevenness of the measurement target surface 201a based on the vibration of the probe 184 caused by the sliding.

  As described above, according to the measurement apparatus 101 of the present embodiment, when the holding unit 104 holds the edge portion of the measurement target surface 201a, the base 103 is positioned at the circular center of the measurement target surface 201a of the metal disc 201. Accordingly, the dial gauge 25 rotates in a plane parallel to the measurement target surface 201a with the rotation of the measurement arm 105 around the base portion 103, and thus the metal disk 201 whose outer edge has a circular shape. It is possible to accurately measure the state of distortion of the surface (measurement target surface 201a).

  Furthermore, in the measuring apparatus 101 of the present embodiment, the connecting portion 107 includes a radial bearing 187 and a thrust bearing 188. For this reason, the measurement arm 105 rotates very smoothly around the axis AX. As a result, rattling that occurs at the connecting portion 107 is eliminated, and the measurement of the distortion of the surface of the metal disk 201 (measurement target surface 201a) by the dial gauge 106 becomes even more accurate.

  In the present embodiment, the measuring apparatus 101 includes the four support arms 102, but the number of the support arms 102 is not limited to four. As an example, the measurement apparatus 101 may include six support arms 102, and these support arms 102 may be arranged so as to extend radially at intervals of 60 degrees with the base 103 as the center.

DESCRIPTION OF SYMBOLS 101 Measurement apparatus 102 Support arm 103 Base 104 Holding part 105 Measurement arm 106 Dial gauge (measurement part)
107 Connecting portion 187 Radial bearing 188 Thrust bearing 201a Measurement target surface

Claims (3)

A strain measuring device that measures strain on a measurement target surface having a circular outer edge,
A plurality of long support arms;
A base for holding each of the supporting arms and extending radially in a plane parallel to the measurement target surface;
A holding portion that is provided on the support arm and holds an edge portion of the measurement target surface;
A measurement arm that extends in parallel with the measurement target surface and is extendable in the length direction;
A measurement unit that is provided in the measurement arm and measures distortion of the measurement target surface;
A connecting part for connecting the base and the measuring arm so that the measuring part is rotatable in a plane parallel to the measurement target surface;
A strain measurement apparatus comprising: The connecting portion includes a bearing;
The distortion measuring apparatus according to claim 1. A plurality of the supporting arms are arranged at intervals of 90 degrees,
The distortion measuring device according to claim 1 or 2.

Images