JPH06317506A - Operation processing device and piping layout position setting method - Google Patents

Abstract

PURPOSE:To split the elements of piping quickly and to achieve operation for accurately laying out the piping by setting the intersection assuming only a straight line between the starting and ending points of the piping and the bending radius and then performing an operation to the coordinates of a bending center point. CONSTITUTION:A work station 111 is constituted of a CPU 112, a storage 113, an external storage 115, etc., and is connected to a CAD device 101 by a LAN controller 118. Then, the coordinates of an intersection (virtual point) assuming only a straight line between the starting and ending points of piping and bending radius data from the device 101 are read and then the virtual point coordinates of piping and the bending radius of each virtual point and a piping material name, a piping diameter value, and a coating thickness value are set. Then, the bending center point coordinates of piping and the starting point/ending point of bending are calculated, thus obtaining the coordinate ands the radius of the coating thickness center part. Further, coordinates with each part of piping as a plate element or a beam element are obtained based on it and the data are converted to the data for FEM and then are output. In this manner, a model where elements are split can be created quickly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an arithmetic processing unit and a pipe arrangement position setting method for designing the structural strength of a pipe connected to a compressor such as a refrigeration / air-conditioning device and constantly subjected to vibration.

[0002]

2. Description of the Related Art Refrigeration and air-conditioning equipment includes compressors, heat exchangers,
It consists of main parts such as an expansion valve, which are connected by a piping system, and the piping system is constantly vibrated by a compressor.
If the design of the piping system is insufficient, stress may concentrate on the local parts of the piping and damage may occur.Therefore, structural strength design of the piping is extremely important. We are reconsidering the placement. The structural strength design in the piping system uses an analysis method called the finite element method.In this finite element method, the piping system is divided into innumerable plate elements and the stress distribution when the length and bend of the pipe are changed is calculated. It is checked whether the maximum stress value in the design is exceeded.

Conventionally, for example, as shown in the drawing (FIG. 19 (a)) described on page 154 of the magazine "Machine design", published by Nikkan Kogyo Shimbun, Vol. 33, No. 10 (August 1989 supplement), FIG. Calculate the piping part by trigonometry (conventional example 1), or refer to the corner point input method described on page 116 of Vol.35 No.6 Dec. 1989, published by Ohmsha, Inc., "National Technical Report" magazine. As described above, there is known a method (conventional example 2) of sequentially calculating the piping for each part. (Fig. 19 (b))

[0004]

In the conventional calculation using the finite element method, in order to make a model for element division, division is made along the pipe axis from the start point to the end point of the arranged pipes one after another,
A method of inputting a large amount of data for each plate element or each beam element each time and determining coordinates is adopted, and a designer familiar with a computer repeatedly performs simple work.

Therefore, it takes a lot of time to obtain the finite element model of the entire pipe, and this work is required every time the pipe arrangement is changed, and this work takes a long time, so that the period of product development becomes long. There was a problem. In addition, when it is bent in a complicated manner, there was a problem that due to a mistake in the piping design, it was not connected smoothly at the bent piping part, and the vibration of the compressor was transmitted to the casing via the piping and caused noise. .

The present invention has been made to solve the above problems, and an object of the present invention is to provide an arithmetic unit capable of dividing piping elements in a very short time and capable of arranging accurate piping. I am trying.

[0007]

The arithmetic processing unit according to the present invention finds the stress of each part of piping such as refrigeration / air-conditioning equipment which is connected to equipment serving as a vibration source and has a bent piping portion. Therefore, in an arithmetic processing device that divides each pipe portion into plate elements or beam elements and performs arithmetic processing, the coordinates of each intersection and the bending pipe of this intersection portion where the pipe arrangement is assumed to be a straight line between the start point and the end point of the pipe. First computing means for computing the coordinates of the bending center point of the bending pipe section from the bending radius of the section, and copying the calculation of the bending pipe section gradually in the bending direction with the coordinates of the bending center point as the center of rotation. Second computing means for computing the coordinates of the plate element or beam element of the copy destination,
It is equipped with.

Further, in the pipe arrangement position setting method according to the present invention, the plate element data for the finite element method of each portion of the pipe of the refrigeration / air-conditioning equipment or the like which is connected to the compressor and has a bent pipe portion is arranged. Alternatively, in the pipe placement position setting method of setting the pipe placement position by dividing the calculation into beam elements, the step of virtualizing the pipe position with only straight lines and calculating the virtual intersection coordinates, and the intersection coordinates and beforehand A step of calculating the bending center point of the virtual intersection point from the set bending radius, and a step of gradually copying in the bending direction with the coordinates of the bending center point as the center of rotation to calculate the coordinates of the plate element or beam element of the copy destination. And outputting data for structural analysis of each part of the pipe by the finite element method.

[0009]

According to the present invention, the intersection between the start point and the end point of the pipe is defined by only a straight line and the bending radius of this intersection is set, the coordinates of the bending center point are calculated, and the bending pipe section is set to the bending center point. The coordinates of the plate element or beam element of the copy destination are calculated by gradually copying in the bending direction with the coordinates as the center of rotation. Further, according to the present invention, input data including coordinates of intersections and bending radii are collectively set, stored in a storage device, and further transferred collectively from the storage device to the CPU.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 is a hardware configuration diagram showing an embodiment of the present invention. In FIG.
02 is the CPU (central processing unit) of this CAD device,
Reference numeral 103 is a storage device of the CAD device, 104 is a keyboard of the CAD device, 105 is an external storage device such as a hard disk of the CAD device, 106 is a digitizer for input operation of the CAD device, 107 is a CRT (display) of the CAD device,
108 is a mouse of a CAD device, 109 is an L of a CAD device
It is an AN controller. Further, 111 is a workstation, 112 is a CPU of the workstation, and 113.
Is a workstation for storing input data consisting of coordinates of intersections, bending radii, etc. input by input means such as a CAD device or a keyboard of a workstation, intermediate data, coordinates of each plate element after element division, etc. Storage device 114, a keyboard of a workstation for collectively setting input data such as coordinates of intersections and bending radii, and 115 for storing data passed to a structural analysis program of the finite element method. An external storage device such as a hard disk of the workstation, 116 is a CRT of the workstation, 117 is a mouse of the workstation, and 118 is a LAN controller of the workstation.

FIG. 2 shows the procedure of the work for designing the structural strength of the pipe. In step 201, the coordinates of the intersection (hereinafter referred to as a virtual point), which is a virtual line between the start point and the end point of the pipe, drawn from the CAD drawing. The bending radius is read, the pipe model is created in step 202, the pipe strength is calculated in step 203, the stress distribution map is created in step 204, and the evaluation test is performed in step 205. The present invention mainly relates to the creation of the piping model in step 202 of the above work procedure.

FIG. 3 is a diagram for explaining in detail the processing contents from step 201 to step 202 in FIG. 2. In step 301 in FIG. 3, the specifications of the piping and the layout of the piping are designed by only straight lines, and step 302 is executed. Determine the position of the virtual point of the pipe with. In step 303, the standard pipe bending radius specified for each pipe diameter is designated as it is for each virtual point. Next, in step 304, a virtual point, a start point (an end point that is one of the virtual points of the pipe and indicates the start point of the routing order of the pipe), and an end point (one of the virtual points of the pipe that is the routing order of the pipe). Read the coordinate value of the end point indicating the end point), enter the coordinate values of the virtual point, the start point, and the end point and the bending radius in a table format in step 305, enter the diameter and wall thickness of the pipe in step 306, and At 307, the material name of the pipe is input. Next, in step 308, the coordinate value of each part of the pipe is calculated based on the numerical values input in step 305 and step 306, and in step 309, the finite element method based on the coordinate value of each part of the pipe in step 308 and the material name in step 307. Convert data to input format.

Incidentally, FIG. 4A shows step 30 in FIG.
It is the figure which showed an example of the straight piping output by 1. Further, (B) of FIG. 4 is a layout diagram of piping designed by CAD, FIG. 5 (A) shows the layout of virtual points of the piping to be read, and FIG. 6 is step 305 and step of FIG. Three
06 is an example of a tabular screen for inputting data in step 307. Further, FIG. 5B shows the model of the plate element of the pipe in step 309, which is confirmed in the figure.

As described above, in the present invention, the data input can be set in the tabular format. In this case, the set input data are collectively stored in the storage device 113 or the external storage device 115. Here, batch means that a plurality of data are processed at the same time. In addition, data such as coordinates and bending radius of each virtual point output from the CAD device are shown in FIG.
From the CAD device via the LAN to the workstation at once and stored in the workstation storage device. This can be used as it is as input data, and the data input operation can be omitted.
These data are collectively transferred from the storage device to the CPU 112 and processed.

FIG. 7 is a flow chart showing an example of a portion forming the core of the present invention. Step 30 in FIG.
The contents from 5 to step 309 are shown in more detail. In step 701, setting means for setting the virtual point coordinates of the pipe, the bending radius of each virtual point, the pipe material name, the pipe diameter value, and the wall thickness value, Also, the virtual point coordinates of the pipe, the bending radius of each virtual point, the pipe material name, the pipe diameter value, and the wall thickness value are output to the storage device as the storage unit 710. Next step 7
In 02, the radius or diameter of the central portion of the wall thickness is calculated based on the data of the storage means 710, and in step 703, the bending center point coordinates of the pipe and the bending start point and the bending end point are calculated, and the bending center point is calculated. The coordinates, the bending start point coordinates, the bending end point coordinates, and the radius or diameter of the central portion of the wall thickness are output to the storage device as the storage unit 711.

Next, at step 704, the storage means 710.
Then, based on the data in the storage means 711, it is determined whether or not the input data in step 701 is normal. This step 70
When it is determined that the input data is abnormal in step 4, the process returns to the first step 701 and normal data can be input again.
If it is determined to be normal in step 704, it is determined in step 705 whether each part of the pipe is a bent pipe or a straight pipe. If it is a bent pipe, in step 706 the storage means 711 Based on the data, the coordinates of each part of the curved pipe with a plate element or a beam element are obtained, and are output to the storage device as coordinate data of the curved pipe part of the storage means 712.

When it is determined in step 705 that the pipe is a straight pipe, each piece of straight pipe is output to the storage device of the storage means 712 as plate element or beam element data. Finally, in step 708, the storage means 7
The 12 pieces of data are converted into data for the finite element method and output to the storage device as the data of the storage means 713. Since the data input in step 701 is in tabular format,
The input can be easily operated like a word processor, the input is quick and the operation is easy to learn. Further, since the CRT display of the workstation is in a tabular form, the input data can be confirmed at a glance, and editing such as correction can be easily performed.

FIG. 8 shows the step 70 in FIG. 7 described above.
3 is a flowchart showing the details of the first calculation means of No. 3, first, in step 801, the bending angle shown in (B) is calculated for each virtual point.

[0019]

[Equation 1]

From step 802, the equation of the straight line connecting each virtual point and the center point of bending is calculated.

[0021]

[Equation 2]

The bending center point of each imaginary point is calculated by the equation 2 and

[0023]

[Equation 3]

It is calculated from Finally, step 80
In 4 the coordinates of the bending start point on the central axis of the pipe

[0025]

[Equation 4]

From the above, the coordinates of the bending end point on the central axis of the pipe are

[0027]

[Equation 5]

Calculated from the above and returned.

FIG. 9 shows the details of the second calculation means in step 706 in FIG.
At (b), a vector CP (2) directed from the bending center point C to the bending start point P (2) on the center axis of the pipe and a unit vector Vy parallel to this vector are obtained, and then step 902 is executed. Unit vector V extending from the point P (2) shown in (c) toward the central axis direction of the straight pipe portion connected to this point
z is calculated, and in step 903, a unit vector Vx perpendicular to the plane Sc including the curve of the central axis of the pipe shown in (d) is calculated. Next, in step 904, the bending center point C of the pipe is set as the origin, and the relative coordinate system based on the unit vectors Vx, Vy, and Vz described above is set, and in step 905, (e) in this relative coordinate system is set. The rotation copy matrix [B] of the rotation angle θ shown

[0030]

[Equation 6]

Find at Even if the pipe is twisted in the circumferential direction in the three-dimensional space of the absolute coordinate system as shown in the equation 6, one bend in the bending direction of the curved pipe portion does not actually exist. The reason is that one bending process is performed on one plane during pipe processing. In the element division, there is a method of reflecting the twist in the circumferential direction on each plate element and a method of not reflecting it, but since the error between the calculation results of both can be ignored,
In the present invention, a method that is not reflected and is easy to handle is adopted. In step 906, the conversion matrix [A] from the absolute coordinate system to the relative coordinate system is set.

[0032]

[Equation 7]

Then, the inverse transformation matrix [A] ^-1 is obtained. At step 907

[0034]

[Equation 8]

From the above, the coordinates of each point on the central axis of the pipe are obtained,
At step 908

[0036]

[Equation 9]

After the coordinates of each part of the pipe are obtained, the process returns. In addition, since the equation 8 calculates the coordinates on the central axis of the pipe, the beam element model of the curved pipe portion can be created as it is.

FIG. 10 shows the details of the calculation of the straight pipe portion in step 707 in FIG. 7. In step 1001 in FIG. 7, the unit vector U which is the reference for copying shown in (b) is the virtual point 1. Obtained so as to be parallel to the straight line connecting the virtual points 2, and in step 1002

[0039]

[Equation 10]

Using, the coordinates of each part of the straight pipe are obtained. It should be noted that this equation 10 can be applied to obtain the coordinates on the central axis of the straight pipe portion similarly to the curved pipe portion, so that the beam element model of the straight pipe portion can be created as it is. As described above, since the beam element model and the plate element model of the curved pipe section and the straight tube section use the same calculation formula, there is an error in the coordinate accuracy of the beam element model and the plate element model as in Conventional Example 1. The problem of becoming large does not occur.

FIG. 11 shows the details of the countermeasure when an input error occurs in the input determination in step 704 of FIG. 7, and (a) is an example of a defect in which two curved pipe parts overlap due to an input error, ( (B) shows an example of a defect in which the connecting part of two curved pipe parts is bent due to an input error, and (c) shows an example of a defect in which the joint part of a curved pipe part and a straight pipe part is bent due to an input error. 8A and 8B are diagrams related to a method of determining the presence / absence of an input error such as (A), (B), and (C). In the figure (d), the sum of the lengths a and b is the virtual point P (i) and the virtual point P (i +
When the distance DIS between 1) is exceeded, it is determined that an input error has occurred. In this case, steps 704 to 7 in FIG.
By returning to 01 and re-entering the data, the problem of typographical errors is solved.

FIG. 12 shows an example of data for the finite element method 713 output in step 708 of FIG. 7. In FIG. 12, 1201 is a declaration that a node is a node.
Reference numeral 1202 indicates a node number assigned to each node, 1203 indicates the X coordinate of the node, 1204 indicates the Y coordinate of the node, and 1205 indicates the Z coordinate of the node. 1206 is a declaration that it is a plate element,
Reference numeral 1207 indicates the element number of each plate element, 1208 indicates the card number that defines the thickness of the plate element to be referred to, and 1209 to 1212 indicate the group of node numbers forming the plate element. 121
3 is a declaration of defining a material constant, 1214 is a material number, 1215 is a longitudinal elastic modulus of the material, 1216 is a Poisson's ratio of the material, 1217 is a mass density of the material, 12
18 is a declaration that the thickness of the plate element is defined, 121
9 is the number of the declaration 1218, 1220 is the declaration 1218
No. 1221 is a material constant number to be referred to for the tensile force, 1221 is a plate thickness, 1222 is a material constant number to be referred to the bending of the declaration 1218, and 1223 is a material constant number to be referred to the shearing of the declaration 1218. As described above, it can be seen that the input data for the strength calculation by the finite element method in step 203 of FIG. 2 is generated by the program of the present invention.

FIG. 13 is a diagram showing the definition of virtual points.
In the same figure, the intersection of each pipe when the pipe is virtual with only straight lines is defined as a virtual point. That is, P (1), P
(2), P (3), P (4), ..., P (7) are virtual points. In addition, R (2), R (3), ..., R
(6) indicates the pipe bending radius of each virtual point except the start and end points of the pipe.

FIG. 14 is an explanatory view of a specific case of the virtual point. FIG. 14A shows the virtual point required when the pipe is bent by 180 degrees, and FIG. 14B shows the virtual point. The virtual point required when the pipe is bent in the crank state is shown, and (c) shows the virtual point required when the diameter of the pipe changes. 141 and 14 in each figure
2, 143 are virtual points in the example of the pipe shape shown in these figures. It should be noted that locations where the pipe diameters are different are also treated as virtual points (that is, intersections).

FIG. 15 shows the function and operating method of one embodiment of the program that realizes step 202 of FIG. 2. In FIG. 15, the activation of the program is notified to the operator at step 1501 and then step 1502 is executed. A storage area for the storage device is secured, and the contents to be executed by the operator of the program are selected in step 1503. In step 1504, unnecessary data left in the storage device is organized, and in step 1505, unnecessary messages and figures left on the screen are deleted. Step 1506 is a menu for changing the numerical value contained in the program. As an example, a menu shown on the screen 1521 is the second operation means of step 706 in FIG. 7 or the straight pipe part in step 707 of FIG. It shows the element division ratio of the pipe used in the calculation.

In step 1507, the material name of the pipe, the pipe outer diameter, the pipe wall thickness, the virtual point coordinates of the pipe, and the bending radius of the pipe are input as the setting means of step 701 in FIG. The shape of the pipe input in step 1508 can be checked and the image of division set on the screen 1521 can be confirmed by visually observing the model. In step 1509, it is possible to confirm whether the pipe material name input in step 1507 is registered as data. In step 1510, it is possible to select whether to construct the finite element model of the pipe with plate elements or beam elements. In step 1511, the constraint condition of the pipe can be set. In step 1512, the vibration of the compressor applied to the pipe can be set.
Further, in step 1513, the data from steps 1506 to 1512 and the input data for the finite element method can be separately output to the storage device 115. Further, the past analysis result registered in step 1514 can be viewed. Further, in step 1515, the details of the model resulting from the above analysis can be confirmed. Further, in step 1516, the pipe strength calculation of step 203 of FIG. 2 can be started.

FIG. 16 shows the second portion shown at 1521 in FIG.
This embodiment shows an example of setting the division ratio of the calculation means or the element similarly used for the calculation of the straight pipe section. In the column 1601 on the screen of FIG. Setting, 1602 column sets the number of radial divisions of the connecting portion when using different diameter pipes, 1603 column sets the number of divisions of the straight pipe in the length direction (axial direction) of the pipe,
In 1604, the number of divisions of the curved pipe in the length direction (axial direction) of the pipe can be set. As mentioned above,
When modeling piping with plate elements or beam elements, the number of divisions of the element in the length direction of the piping can be specified individually for the straight pipe part and the curved pipe part, and when using the plate element, The number of divisions of the element in the circumferential direction of the pipe and the radial direction of the connection part of the different diameter pipe can be set individually as appropriate,
The designer can adjust the size of the finite element model of the pipe, and as a result, the calculation time of strength calculation can be speeded up and the calculation accuracy can be optimized.

On the data input screen shown in FIG. 16C, the previous input data is displayed as a default value to simplify the operation. In addition, a menu format has been adopted to accelerate operability. In the case of the different-diameter pipes shown in (a) and (b), the end points P (3) and P of the pipes to be connected as shown in FIG.
The distance ERR in (4) is within a certain value and the point P (3)
And P (4) are determined to have the same coordinates, and FIG.
The end point P of each pipe to be connected as shown in (b)
Distances h1 and h from the straight line connecting the virtual points P (2) and P (5) closest to the ends in the respective pipes (3) and P (4)
When both 2 are within a certain value and it can be determined that the vicinity of each pipe end point is on the same straight line, as shown in (a) and (b) of FIG. The number of divisions is 1602.

FIG. 18A shows an example in which different diameter pipes are connected according to the criteria of FIG. 16 and these are modeled by plate elements. Further, (B) is an axial cross-sectional view of the pipe in the vicinity of the connection portion when the outer diameter of the pipe is changing, and the black circles shown in the figure indicate the nodes of the plate element. (C) is an axial cross-sectional view of the pipe in the vicinity of the connection portion when the pipes have the same outer diameter but different wall thicknesses, and the black circles shown in the figure indicate the nodes of the plate element in this case. As described above, according to the present invention, it is possible to connect different diameter pipes which are generally considered to be difficult to connect.

Further, in the present invention, it is possible to construct each element of the piping with the minimum input data.

Needless to say, the present invention can work on a plurality of workstations connected to the LAN. That is, the workstation 1
11 is an example in which steps 701 to 708 of FIG. 7 are performed on step 11.
The same effect as the present invention can be obtained in the case where steps 1 to 704 are performed by one workstation and steps 705 to 708 in the same figure are performed by another workstation.

In the conventional method for creating a model, the number of input points in operation was large as follows. In other words, in the first stage, enter the four items of the coordinates of the center point of the pipe end, the coordinates of the nodes, the diameter of the pipe, and the wall thickness, and in the second stage, in the case of a straight pipe, declare that it will extend in the length direction, and copy it. Enter the four items: number of times, copy direction, and distance in the length direction of the copy destination. For curved pipes, the coordinates of the copy source, the declaration of bending, the coordinates of the bending center, the bending angle, the number of times of copying, the end point of the bending pipe. It is necessary to enter 6 items such as coordinates or ending direction. On the other hand, in the case of the present invention, the number of divisions, the diameter of the pipe, and the wall thickness can be input at the initial stage or the numerical values of other models can be used as they are. It is only necessary to input the two items of the radius, and it is not necessary to individually recognize the coordinates of the bending start point and the bending end point.

[0053]

According to the present invention, since piping elements can be constructed with a minimum of data, it is possible to create a model in which the piping elements are divided into a short time, which can shorten the product development period and use the bending center coordinates as a reference. Since the piping layout is designed in, the dimensions of each part of the piping can be automatically checked at the same time as element division, and good product quality can be maintained. Further, the present invention has an effect that the processing time can be shortened and the information can be collectively managed because the input data are collectively set and stored in the storage device, and are collectively transferred from the storage device to the CPU.

[Brief description of drawings]

FIG. 1 is a hardware configuration diagram showing an embodiment of the present invention.

FIG. 2 shows an outline of a procedure of work for designing a pipe strength according to the present invention.

FIG. 3 shows a procedure of a finite element model creation work of piping using the present invention.

FIG. 4 is a display example in which a straight line and an intersection point (virtual point) are displayed on a CAD screen when a piping design by CAD of an outdoor unit of an air conditioner is performed with only a straight line.

FIG. 5 is a diagram in which the result of dividing the piping portion of FIG. 4 and virtual points and elements is displayed on the screen.

FIG. 6 is a diagram showing a display example for inputting data in a tabular format as an embodiment of the present invention.

FIG. 7 shows an embodiment of software which is the core of the present invention, and is a flowchart for obtaining each coordinate of piping.

FIG. 8 is a detailed flowchart of a first calculation forming a part of FIG.

9 is a detailed flowchart of a second calculation which forms a part of FIG.

10 is a detailed flowchart of a calculation of a straight pipe section forming a part of FIG. 7. FIG.

FIG. 11 is a reference diagram for determining an example of a defect in a pipe connecting portion caused by an input error and determining the defect.

FIG. 12 is a diagram showing data passed to a structure analysis program as an output result according to the present invention.

FIG. 13 is a diagram showing a relationship between a position of a pipe intersection (imaginary point) and a bending radius.

FIG. 14 is a diagram showing a relationship between a position of an imaginary point and a bending radius when the pipe is bent 180 degrees or in a crank shape and when pipes having different diameters are connected to each other.

FIG. 15 is a diagram showing a display example of a menu screen according to the present invention.

FIG. 16 is a diagram showing an example of performing the element division according to the present invention in the circumferential direction and the radial direction, or in the length direction of the straight portion and the bending direction of the curved pipe portion, and an example of an input screen thereof.

FIG. 17 is a reference diagram showing a condition for the ends of two pipes to be on the same straight line.

FIG. 18 is a diagram showing positions of nodes when different diameter pipes are connected to each other.

FIG. 19 is a diagram of a beam element model and a plate element model created by conventional model creation or a beam element model created by a conventional corner point input method.

[Explanation of symbols]

 101 CAD device 102 CPU 103 storage device 104 keyboard 105 DISK 106 digitizer 107 CRT 108 mouse 109 LAN controller 111 workstation 112 CPU 113 storage device 114 keyboard 115 DISK 116 CRT 117 mouse 118 LAN controller 141 virtual point 142 virtual point 143 virtual point 710 Storage means 711 Storage means 712 Storage means 713 Storage means 1201 Node declaration 1202 Node number 1203 Node X coordinate 1204 Node Y coordinate 1205 Node Z coordinate 1206 Plate element declaration 1207 Plate element element number 1208 Plate element thickness etc. No. 1209 Nodal number of plate element 1210 Nodal number of plate element 1211 Nodal number of plate element 1212 Nodal number of plate element 213 Declaration of Material Constants 1214 Material Number 1215 Material Elastic Modulus 1216 Material Poisson's Ratio 1217 Material Mass Density 1218 Declaration of Plate Element Thickness 1219 1218 Number 1220 1218 Tensile Force 1221 Plate Thickness 1222 1218 Material for Bending Constant number 1223 Material constant number for 1218 shear

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] December 2, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Fig. 11

[Correction method] Change

[Correction content]

FIG. 11 is an explanatory diagram for an example of a defect in a pipe connecting portion caused by an input error and a defect determination.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] Fig. 17

[Correction method] Change

[Correction content]

FIG. 17 is a diagram showing conditions for the ends of two pipes to be on the same straight line.

Claims (6)

[Claims] 1. A pipe element or a beam element is used to obtain the stress of each part of piping such as a refrigerating / air-conditioning equipment connected to a device as a vibration source and arranged with a bent piping part. In an arithmetic processing unit that performs divided arithmetic processing, the bending of the bending pipe section is calculated from the coordinates of each intersection and the bending radius of the bending pipe section at this intersection where the piping arrangement is assumed to be a straight line between the start point and the end point of the pipe. First to calculate the coordinates of the center point
And second calculating means for calculating the coordinates of each plate element or beam element of the copy destination by copying the calculation of the bending pipe section little by little in the bending direction with the coordinates of the bending center point as the center of rotation. An arithmetic processing unit comprising: 2. The setting means collectively sets the input data of the start point / end point of the pipe, the coordinates of each virtual intersection, and the bending radius of each intersection. The arithmetic processing device described. 3. The arithmetic processing unit according to claim 2, wherein the data set by the setting means is collectively passed to the first arithmetic means. 4. The arithmetic processing unit according to claim 1, wherein the number of divisions of the plate element or the beam element in the axial direction of the pipe can be changed between the straight pipe portion and the curved pipe portion. 5. A plate element is provided at a different-diameter connecting portion of a different-diameter connecting pipe in which at least one of the outer diameter and the inner diameter of the pipe changes, and the plate element is connected to the plate element of each portion of the pipe. The arithmetic processing unit according to claim 1. 6. The arrangement position of the pipe is calculated by dividing the stress of each part of the pipe of the refrigeration / air-conditioning equipment, etc., which is connected to the compressor and has a bent pipe portion, by dividing it into plate elements or beam elements. In the method of setting the pipe arrangement position to be set, the start point of the pipe
Virtualizing the pipe position with only a straight line between the end points, calculating the virtual intersection point coordinates, and calculating the coordinates of the bending center point of the bending pipe portion of the virtual intersection point from the intersection point coordinates and the preset bending radius. And the calculation of the bending pipe part is copied little by little in the bending direction with the coordinates of this bending center point as the center of rotation to calculate the coordinates of each plate element or beam element of the copy destination, and the pipe parts are calculated by the finite element method. And a step of outputting data for performing structural analysis of the pipe arrangement setting method.