KR101246060B1 - Method for calculating shrinkage based on gap state - Google Patents

Abstract

Disclosed is a method of calculating a shrinkage amount considering a gap situation.
A first factor extraction step using a global shipbuilding computer aided design (GSCAD) for a block according to an embodiment of the present invention; Extracting a second factor using the measurement of the block; Securing a shrinkage amount through finite element analysis considering the extracted factor; Deriving an inference prediction equation using the secured shrinkage; The method may include determining the accuracy of the calculated amount of shrinkage by comparing the calculated amount of shrinkage through the inference prediction equation with a measured value measured by the actual measurement of the block.

Description

Shrinkage calculation method considering gap situation {METHOD FOR CALCULATING SHRINKAGE BASED ON GAP STATE}

The present invention relates to hull block assembly, and more particularly, to a method for calculating the shrinkage amount considering the gap situation when assembling the hull block by welding.

In general, block fabrication and assembly are very important processes in the shipbuilding industry.

Shipbuilding is largely carried out through the entire manufacturing process, including small-scale assembly, heavy-assembly, and counter-assembly, as well as field manufacturing processes including pre-Erection (PE) and dock block mounting of the contrasting control block. ought.

Looking at the vessel terminology, the margin in the block fabrication may mean a dimension value that is increased in advance in consideration of the shrinkage of the coupling portion due to the welding in order to prevent the dimensions of the welding object to be reduced by welding.

In addition, the degree may mean dimensional accuracy (Dimensional Accuracy) or precision.

In addition, the block pre-mounting setting and pre-loading is to set the block using a gap in consideration of the margin according to the welding shrinkage, so that the inter-block matching can be made for the block assembly, and then welding the set block Can mean.

Here, the gap may mean the length of the band between blocks.

In addition, mounting setting and mounting may mean setting the block to be matched and then welding the set block.

In other words, the joining method of welding is used in a process of stacking and connecting the intermediate products in the assembled block unit.

While welding has several advantages, it causes a problem of deformation.

In particular, the biggest problem in block coupling is that the desired dimensional quality is not easily obtained due to the in-plane deformation of the steel sheet through welding.

As shown in FIG. 1, the block setting operation according to the related art includes a block level fitting step S10, a block straightness fitting step S20, and a block mounting fitting step S30.

In the block level fitting step (S10), two contrasting blocks (1, 2) to be a preloaded block to be set by the operator are selected, and after setting a setting schedule, the two contrasting blocks (1, 2) are divided into a general block level and Straightness is also placed above the fitting facility (3).

The operator then measures the upper or lower support position of each of the two control blocks 1, 2 using the leveling device of the installation 3 and calculates the level adjustment value through a water calculation.

The operator then lifts up each control block 1, 2 using the hydraulic transmission of the plant 3 above the level adjustment value previously calculated. After adjusting the support height by the level adjustment value, put down each control block (1, 2) using the hydraulic power transmission again.

Finally, the operator measures the vicinity of the support position of the upper or lower portion of each control block 1, 2 using a leveler. Based on the measured values, it is checked whether the level of each support position is correct so that the levels of the two control blocks 1 and 2 coincide with each other.

In the block straightness alignment step S20, the block straightness may be adjusted by two methods using a seal 4 and a three-dimensional measuring instrument (not shown).

First, in the straightness matching method using the thread 4, one inner material such as a long paper, a girder, and a frame is selected and marked at a predetermined length on both rear end portions of the corresponding inner material of each of the control blocks 1 and 2. Thereafter, the inner end of the corresponding inner block of one control block (1) is connected to the thread 4 to the end of the inner member of the other control block (2).

After that, each control block (1, 2) is moved so that the seal and the marking line are in a straight line by using a hydraulic transmission.

On the other hand, in the straightness matching method using a three-dimensional measuring instrument, the main inner material such as girder, frame is selected to measure the ends of the corresponding inner material of each control block (1, 2). Based on the measured values, a moving value for matching the straightness of the two control blocks 1 and 2 is calculated. Check and measure after adjusting by using hydraulic power transmission.

In the block mounting alignment step (S30), after the measurement of the mounting of the control block (1, 2) to be the linear mounting block is adjusted, the gap adjustment operation is in progress.

That is, in the gap adjusting operation, the mounting of the control blocks 1 and 2 is measured using a tape measure, or the main girders and the frame ends are measured as in the previous step using a three-dimensional measuring instrument. Measure the mounting.

Thereafter, the operator obtains the design mounting value of the preloaded block through the drawing and compares it with the measured values of the control blocks 1 and 2 to obtain a gap value and setting mounting value in which the welding shrinkage is appropriately considered through experience.

In addition, the operator checks the level and straightness after moving the two control blocks (1, 2) corresponding to the obtained value by using the hydraulic transmission.

However, in the prior art, long-term skilled practitioners perform the on-board setting and the on-board, or on-board setting and mounting based on their know-how, so that a uniform value cannot be applied to everyone. have.

Due to this reason, after the preloading or mounting setting, a rework such as re-cutting or overlay welding is inevitably generated, and additional costs arise.

In addition, in the case of a skilled worker with a long experience, intangible loss that takes a long time in acquiring such a method also occurs, which is a cause of deterioration of the assembly block.

Embodiments of the present invention provide a method for calculating the weld shrinkage considering the gap, so that no deviation occurs in the result at the time of block setting according to the operator's experience or skill.

According to an aspect of the invention, the first factor extraction step using a global shipbuilding computer aided design (GSCAD) for the block; Extracting a second factor using the measurement of the block; Securing a shrinkage amount through finite element analysis considering the extracted factor; Deriving an inference prediction equation using the secured shrinkage; A contraction amount calculation method may be provided in consideration of a gap situation including comparing the contraction amount calculated by the inference prediction formula with a measured value measured by a block and determining the accuracy of the contraction amount calculated.

In the embodiment of the present invention, by calculating the shrinkage amount in consideration of the gap condition of the block, a high degree of shrinkage prediction is possible.

In addition, the embodiment of the present invention is configured by the contraction amount calculation unit of the logic type for the block virtual assembly simulator, the inference prediction formula can automatically calculate the shrinkage of the block can accurately and easily predict the shrinkage considering the gap situation.

In the description of the present invention, the automatic calculation may mean that when an input value is input by using a computer, an arithmetic operation is performed by a predefined calculation unit or the like to output.

In addition, the embodiment of the present invention by using the extracted factor in the simulation by using the finite element analysis to secure the amount of shrinkage in advance, based on this induces the inference prediction formula containing the three factors, and then actually the By measuring the measured value which measured the dimension before and after welding to the inference prediction formula, the shrinkage amount calculation value accuracy is discriminated, and it is possible to calculate a much higher shrinkage amount.

Thus, the amount of shrinkage in consideration of the gap situation calculated through the embodiment of the present invention may be applied to a simulator for block virtual assembly or block setting to enable highly accurate simulation.

Therefore, according to the embodiment of the present invention, the modification of the block can be made, and it is possible to prevent the further modification or measurement by the generation of deformation by predicting and reflecting the deformation to occur in the process in advance.

1 is a flowchart illustrating a block setting method according to the prior art.
2 is a block diagram showing an entire system to which a shrinkage calculation method considering a gap situation according to an embodiment of the present invention is applied.
3 is a flowchart illustrating a shrinkage calculation method considering a gap situation according to an embodiment of the present invention.
4 is a screen capture diagram showing a first factor extraction step using GSCAD in the shrinkage calculation method shown in FIG.
FIG. 5 is a diagram illustrating a second factor extraction step using block measurement in the shrinkage calculation method shown in FIG. 3.
FIG. 6 is a view for explaining a shrinkage securing step through finite element analysis in which an extraction factor is considered in the shrinkage calculation method shown in FIG. 3.
FIG. 7 is a graph comparing the amount of shrinkage and the block measurement through the finite element analysis illustrated in FIG. 6.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

2 is a block diagram showing an entire system to which a shrinkage calculation method considering a gap situation according to an embodiment of the present invention is applied.

As shown in FIG. 2, the present embodiment derives an inference prediction equation in a process of extracting and processing a factor necessary for calculating a shrinkage amount for a hull block manufacturing management system, and uses the inference prediction equation to determine a gap state between blocks. The amount of shrinkage considered can be predicted.

The inference prediction equation presented in this embodiment may be configured as a modular shrinkage calculator 310 having a logic or computer algorithm for a block virtual assembly simulator to automatically calculate the shrinkage of a block in a block simulation and the like. It is possible to accurately and easily estimate the shrinkage amount considering the gap situation.

This embodiment can be applied to the hull block production management system, for example.

Here, the hull block production management system is integrated DB server system 100 that records, manages, and provides various information, the tracking system 200 for the cause of dimensional quality defects using margin analysis and update, and the block correction in consideration of the shrinkage or It may include a correction amount setting value determination system 300 for managing the setting, and a block monitoring system 400 capable of real-time block monitoring and setting simulation.

Here, the shrinkage amount calculation unit 310 and the GSCAD 320 may be used in combination with a simulator provided in the correction amount setting value determination system 300.

For example, when it is necessary to calculate the amount of shrinkage due to welding of the block during the use of the simulator, the amount of shrinkage calculation unit 310 may be executed. In this case, the amount of shrinkage calculation unit 310 may provide data on steel grade, plate thickness, and gap of the block. By using the input value of Equation 1 can be configured to automatically calculate the amount of shrinkage considering the gap condition of the block.

3 is a flowchart illustrating a shrinkage calculation method considering a gap situation according to an embodiment of the present invention.

As shown in FIG. 3, the present embodiment includes a first factor extraction step S100 using a global shipbuilding computer aided design (GSCAD) for a block, and a second factor extraction step S200 using a measurement of the block. can do.

In addition, the present embodiment and the step of ensuring the shrinkage through the finite element analysis considering the extracted factor (S300); Deriving an inference prediction equation using the secured shrinkage amount (S400); The method may include determining the accuracy of the calculated amount of shrinkage by comparing the calculated amount of shrinkage through the inference prediction equation with the measured value measured by the block (S500).

In the present embodiment, the extracted factor may be considered in the finite element analysis may mean that the extracted factor is used or used in the finite element analysis.

In addition, in order to use the block GSCAD in this embodiment, or to use the initial gap between blocks by measurement, GSCAD information DB 101 or block dimension information managed by the integrated DB server system 100 shown in FIG. DB 102 may be used.

In the present embodiment, the first factor may be the plate thickness and steel grade of the block, and the second factor may be the initial gap between the blocks.

First, in the first factor extraction step S100, the first factor may be extracted by a factor extraction custom command of GSCAD, which is a shipyard design CAD program.

Here, the parameter extraction custom command is operated in GSCAD to generate a block shrinkage characteristic extraction module, and when the target blocks to be preloaded or mounted are designated, including the first factor from the GSCAD information of the respective designated blocks. The block shrinkage characteristic value information may be programmed to be extracted in a text form by the block shrinkage characteristic value extraction module and output in the GSCAD.

4 is a screen capture diagram showing a first factor extraction step using GSCAD in the shrinkage calculation method shown in FIG.

Referring to FIG. 4, in a first factor extraction step S100, a first process S110 of opening and loading a modeling CAD information file of a target block in the GSCAD 320 may be performed.

Thereafter, the second process S120 in which the argument extraction custom command 321 is operated in the GSCAD 320 may proceed.

Here, the parameter extraction custom command 321 may be selected and operated by a user's operation in a custom command menu of a tool item among execution tools of the GSCAD 320.

In addition, the parameter extraction custom command 321 is provided with a module operation button 322, so that when the operator clicks the module operation button 322, the block shrinkage characteristic value extraction module 323 is generated (S130). This can be done.

That is, in the third process S130, the block shrinkage characteristic value extraction module 323 may be generated at the bottom of the edit menu screen.

Here, the block shrinkage characteristic value extraction module 323 has a confirmation area indicated by 'PE block' and a confirmation area indicated by 'Else', and an extraction result button 324 is disposed beside the block shrinkage characteristic value extraction module 323. It may be. Here, the extraction result button 324 is in an inactive state.

The confirmation area marked 'PE block' may play a function of activating the work window 325 to select a target block according to its check mark expression (eg, a mouse click by a user).

The confirmation area marked 'Else' may be responsible for displaying another work window (not shown) according to the display of his check mark.

Here, when the worker clicks on the confirmation area marked as 'PE block', a fourth process S140 of activating the work window 325 may be performed.

Here, the work pane 325 may be a workspace explorer interface that may be arranged together with the main screen of the GSCAD 320.

That is, in the fourth process S140, target blocks to be preloaded or mounted may be designated as the target blocks are respectively clicked on the work window 325.

In this case, the block shrinkage property extraction operation may be automatically performed while the block file name of the clicked area and the color of the surrounding area are changed.

In the block shrinkage characteristic value extraction operation, block shrinkage characteristic value information including the first factor may be extracted in a text form by the block shrinkage characteristic value extraction module 323 from the GSCAD information of the designated blocks, respectively.

When the block shrinkage characteristic value extraction operation is completed and completed, the fifth process S150 of activating the extraction result button 324 may be performed.

The worker may click the activated extraction result button 324 to proceed with a sixth step S160 in which the extraction result is output in a text format in the popup window 326 of the GSCAD.

The pop-up window 326 may include information about the total welding length of the block (welding), the steel type of the block, and the plate thickness of the block.

The second factor extraction step S200 illustrated in FIG. 3 may be described with reference to FIG. 5.

FIG. 5 is a diagram illustrating a second factor extraction step using block measurement in the shrinkage calculation method shown in FIG. 3.

As shown in FIG. 5, the initial gap between the blocks 10 and 20, that is, the initial cytium length between the blocks 10 and 20 is the actual measurement using the measuring device 500 such as IGPS (Indoor GPS). Can be obtained through

The measurement apparatus 500 may include a measurement means 510 including a single sensor and a hub for IGPS (Indoor GPS), a wired / wireless network 520, a host computer 530, and a measurement management server 540.

The initial gap acquired through the measurement apparatus 500 may be recorded and stored and managed in the block dimension information DB 102 for each target block and adjacent blocks.

The measurement management server 540 may be configured to be linked to the shrinkage calculation unit of the aforementioned GSCAD or correction amount setting value determination system.

These factors (eg plate thickness, steel grade, initial gap) need to be processed to calculate the shrinkage of the block.

In addition, the present embodiment in the step of securing the shrinkage through the finite element analysis considering the extracted factor (S300), first, according to the finite element analysis reflecting the various steel grades, plate thickness and the shape of the block currently used in the block manufacturing Simulation can be performed to predict the amount of shrinkage for analysis in advance.

For example, in the present embodiment, as the finite element analysis method, a 2D analysis method based on the strain boundary method may be used. At this time, it is possible to analyze the block welding shrinkage using each of the inherent strain of the base material and the welding wire.

For example, FIG. 6 is a view for explaining a step of securing shrinkage through finite element analysis in which an extraction factor is considered in the shrinkage calculation method shown in FIG. 3.

Referring to FIG. 6, as in (a), as a comparative example, in the related art, the heat input amount is interpreted by applying only the filler of the welded portion, but in (b) according to the present embodiment, the welding heat affected portion ( We can analyze welding shrinkage considering HAZ (Heat Affected Zone) area.

In addition, in this embodiment, an analysis method in consideration of the length and the number of passes can also be used as shown in (c).

For example, the analysis may be performed using the length 600 of the welded part and the number of passes of the primary pass 610, the secondary pass 620, and the tertiary pass 630 according to the multilayer welding method.

FIG. 7 is a graph comparing the amount of shrinkage and the block measurement through the finite element analysis illustrated in FIG. 6.

As shown in FIG. 7, the present embodiment can secure an amount of shrinkage through the finite element analysis as described above, and can compare and analyze the measured value obtained by actual measurement.

In the graph, the horizontal axis may mean a heat input parameter including a plate thickness t and a gap G of the block, and the vertical axis may mean a transverse shrinkage of the in-plane deformation of the block.

Subsequently, in this embodiment, a step (S400) of deriving an inference prediction equation using the secured shrinkage amount may proceed.

In this step (S400), the inference prediction formula containing the three factors obtained above is inferred.

That is, after determining the representative thickness and the gap, a design of experiment (DOE) may be performed, and a transverse contraction inference, that is, a prediction inference equation, may be derived by regression through DOE.

The predictive reasoning formula thus predicted may be defined by Equation 1 below.

은 횡수축량, t는 블록의 판 두께, G는 용접시 블록간 갭, a, b, c, d, e, f는 [표 1]의 강종별 상수를 의미할 수 있다.here,

Is the amount of lateral shrinkage, t is the plate thickness of the block, G is the inter-block gap during welding, a, b, c, d, e, f may refer to the steel type constants in [Table 1].

Subsequently, in the present embodiment, a step (S500) of determining the accuracy of the shrinkage calculated value may be performed by comparing the shrinkage calculated value through the inference prediction formula with the measured value measured by the block.

In other words, in order to verify the inference prediction equation and improve the accuracy, the measurement of the dimensions before and after the actual block mounting welding can be performed, and a high degree of inference prediction equation can be used to calculate the shrinkage considering the gap situation.

As such, the present embodiment provides a method of calculating the amount of shrinkage that can be used in setting the block preload (PE) and preload or mounting and mounting, thereby making the existing work more efficient.

In addition, the present embodiment can be easily performed by the ordinary non-skilled person to block setting work that can only be done by the existing skilled person and can easily and easily perform trial and error through manual labor.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, You will understand. For example, a person skilled in the art can change the material, size and the like of each constituent element depending on the application field or can combine or substitute the embodiments in a form not clearly disclosed in the embodiment of the present invention, Of the range. Therefore, it should be understood that the above-described embodiments are to be considered in all respects as illustrative and not restrictive, and that such modified embodiments are included in the technical idea described in the claims of the present invention.

100: integrated DB server system 200: tracking system for poor quality measurement
300: correction amount setting value determination system 310: shrinkage calculation unit
320: GSCAD 400: block monitoring system
500: measuring device

Claims (5)

Extracting a first factor using a global shipbuilding computer aided design (GSCAD) for the block;
Extracting a second factor using the measurement of the block;
Securing shrinkage through finite element analysis considering the extracted first and second factors;
Deriving an inference prediction equation using the secured shrinkage;
And comparing the calculated amount of shrinkage through the inference prediction formula with a measured value of actual measurement of the block, and determining the accuracy of the calculated amount of shrinkage.
The first factor is the plate thickness and steel grade of the block,
The second factor is characterized in that the initial gap between the blocks
Shrinkage calculation method considering gap situation.
delete The method of claim 1,
The first factor is,
The block shrinkage characteristic value information including the first factor is generated from the GSCAD information of each of the designated blocks when the target blocks to be preloaded or mounted on the block are designated by operating in the GSCAD to generate a block shrinkage characteristic extraction module. Characterized by the block shrinkage feature extraction module in the form of text extracted by a parameter extraction custom command programmed to be output on the GSCAD
Shrinkage calculation method considering gap situation.
The method of claim 1,
The first factor extraction step,
A first step of opening and loading a modeling CAD information file of a target block in the GSCAD;
A second process of operating a parameter extraction custom command using the custom command menu of the GSCAD,
A third process of generating a block contraction characteristic value extraction module according to a module operation button operation of the argument extraction custom command;
A fourth process of activating a work window by using a confirmation region marked as 'PE block' of the block shrinkage characteristic extraction module;
A fifth process of extracting block shrink characteristic value information including the first factor from a GSCAD information in a text form by specifying a target block in the work window, and extracting the button to activate the extraction result button;
And a sixth process of outputting the extracted result in a text format in a pop-up window of GSCAD by using the extracted result button.
Shrinkage calculation method considering gap situation.
The method of claim 1,
The inference prediction equation is defined by the following equation (1)
Shrinkage calculation method considering gap situation.
(1)

In equation (1),

Is the amount of lateral shrinkage, t is the plate thickness of the block, G is the gap between blocks during welding, and a, b, c, d, e and f are the steel type constants in Table (1).
(Table 1)

Images