CN107085649B - Finite element model and method for preventing movement during part forming - Google Patents
Finite element model and method for preventing movement during part forming Download PDFInfo
- Publication number
- CN107085649B CN107085649B CN201710466108.3A CN201710466108A CN107085649B CN 107085649 B CN107085649 B CN 107085649B CN 201710466108 A CN201710466108 A CN 201710466108A CN 107085649 B CN107085649 B CN 107085649B
- Authority
- CN
- China
- Prior art keywords
- positioning
- lug
- web surface
- holes
- locating
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
- G06F30/23—Design optimisation, verification or simulation using finite element methods [FEM] or finite difference methods [FDM]
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D26/00—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces
- B21D26/02—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces by applying fluid pressure
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/10—Geometric CAD
- G06F30/15—Vehicle, aircraft or watercraft design
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2111/00—Details relating to CAD techniques
- G06F2111/20—Configuration CAD, e.g. designing by assembling or positioning modules selected from libraries of predesigned modules
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2113/00—Details relating to the application field
- G06F2113/28—Fuselage, exterior or interior
Abstract
The invention provides a finite element model and a method for preventing movement during part forming. Two ends and the middle position of the web surface of the part are respectively provided with a rectangular positioning lug, and the size of the positioning lug is determined according to the size of the part; each positioning lug is provided with two positioning holes, the two positioning holes are on the same straight line, and an angle of 45 degrees is formed between the two positioning holes and the bottom edge of the positioning lug, so that firm and reliable positioning is ensured; wherein, the locating holes on the locating lugs at the two sides and above are close to the sinking position of the web surface. The invention can reduce manual shape correction of workers and improve the surface quality of products; the production efficiency of the frame-edge parts is improved, and the requirement of mass and fast-paced production rate is met.
Description
Technical Field
The invention belongs to the field of sheet metal alignment, and relates to a finite element model and a finite element model method for preventing movement during part forming.
Background
At present, in the design process of aircraft parts, arc-shaped bent edges are arranged, the bent edges are extremely narrow, the parts with sags on the bent edges are gradually increased, the parts are difficult to form, the phenomena of heavy dragging and deformation, dislocation, inaccurate positioning, heavy torsional deformation and unrepairable parts easily occur in the hydraulic forming process of the parts, the subsequent heat treatment deformation is more serious, and the parts can only be scrapped and cannot be repaired when the problems are overlapped together.
At present, only hydroforming can be adopted for the parts with the sinking of the narrow flange band of the long arc-shaped web surface at home and abroad, and the phenomenon of serious torsion, dragging and deformation of the parts still exists in the hydroforming process, so that a lot of troubles are brought to subsequent trimming. The traditional positioning method is to add three square positioning lugs with the size of 10mm multiplied by 10mm, if the sinking is not pressed in place or the sinking is not pressed out at all according to the traditional positioning method, the condition of meat deficiency of the sinking part is more occurred, the appearance of the part is far different from the digital-analog requirement, and the appearance of each part of a batch of dozens of parts is different, the rejection rate is extremely high, so that the searching of a reasonable positioning mode suitable for the part is very important. It is therefore an object of the present invention to provide a longer positioning tab that follows the contour of the part. The positioning device with the shape-following long and narrow positioning lugs, which can form the whole complex arc-shaped part, has the advantages of compact structure, simplicity and novelty, can realize the formation under irregular and non-specified conditions in special environments, and meets the extreme special requirements in the production of sheet metal parts of airplanes.
The hydraulic forming of rubber bags is one of the main methods of sheet metal forming, and a large number of sheet metal parts formed by the hydraulic forming of rubber bags are arranged on an airplane. At present, the rebound problem of parts in the rubber bag hydraulic forming process is endless, and the rebound problem in the forming process is mainly studied in China, so that a plurality of manual correction processes are increased, and the production efficiency and the fatigue life of sheet metal parts are greatly reduced. The rebound influences the overall dimension of the part, and the problems of inconsistent assembly, unstable assembly quality and the like can be caused. The rubber bag hydraulic forming process has another obvious problem of inaccurate positioning, and the phenomenon of pulling in the forming process is serious, so that a large number of unnecessary manual correction can be caused, the production efficiency of a company and the fatigue life of sheet metal parts are seriously influenced, the rebound problem in the rubber bag hydraulic forming process can be studied through a numerical simulation technology, and the positioning mode and the position of a positioning hole can be simulated.
Disclosure of Invention
Aiming at the problems existing in the prior art, the invention adopts a MARC finite element simulation model to study the influence of the relative arrangement of the positioning lug and the positioning hole on the forming of the part rubber bag, and provides a finite element model and a method for preventing the movement during the forming of the part.
The technical scheme of the invention is as follows:
a finite element model for preventing the movement of a part during shaping comprises a web surface of the part, a positioning lug and a positioning hole. The parts are airplane frame edge parts, basically have long and narrow arc structures, large radian, long length, narrow web surface and sunken flanging belts, and are basically similar in forming mode. The part is an aircraft frame flange-like part for the mounting of an aircraft skeleton structure, the structure of which is of great importance for the whole aircraft assembly.
The web surface of the part is arc-shaped, the web surface is narrow, the flanging belt is sunken, and the allowance of 1mm is added to the sunken position of the web surface. Two ends and the middle position of the web surface of the part are respectively provided with a rectangular positioning lug, and the size of the positioning lug is determined according to the size of the part; each positioning lug is provided with two positioning holes, the two positioning holes are on the same straight line, and an angle of 45 degrees is formed between the two positioning holes and the bottom edge of the positioning lug, so that firm and reliable positioning is ensured; wherein, the locating holes on the locating lugs on the two sides and above are close to the sinking position of the web surface, so that the pulling deformation, dislocation, inaccurate locating and torsional deformation of the part during the forming on the rubber bag hydraulic press are avoided.
A method of preventing movement during part forming comprising the steps of:
1) Milling the unfolding shape of the part according to the two-dimensional unfolding data set with the process allowance, checking the surface quality of the unfolding material, and determining whether the surface quality is qualified; if cracks or large pits exist, the surface quality is unqualified, the next forming process cannot be performed, and the reprocessing is needed to avoid subsequent cracks.
2) Confirm the size of locating hole and its position in locating the lug:
the size of the positioning hole is determined according to the width degree of the web surface of the part, and the positioning hole is larger as the part is narrower and longer, so that the phenomenon of pulling of the part during hydroforming and subsequent manual trimming is avoided.
Two positioning holes are formed in each positioning lug, the two positioning holes are positioned on the same straight line, and an angle of 45 degrees is formed between the two positioning holes and the bottom edge of each lug, so that firm and reliable positioning is ensured; wherein, the locating holes on the locating lugs on the two sides and above are close to the sinking position of the web surface, so that the pulling deformation, dislocation, inaccurate locating and torsional deformation of the part during the forming on the rubber bag hydraulic press are avoided.
3) Installing and positioning lugs: two ends and the middle position of the web surface of the part are respectively provided with a rectangular positioning lug.
4) The processing technology comprises the following steps: judging whether the process allowance is added at the convex bent edge of the part, and if the process allowance is not added, supplementing the process allowance; if the process allowance is added, the sinking position of the part needs to be additionally added with the process allowance of 1mm, and the requirement is met after the sinking position is formed.
The design principle of the invention is as follows: according to the actual use requirement, the operation comfort level of workers and the avoidance condition of surrounding environment are considered when the device is used, the possible problems in the production of parts are predicted, a Marc simulation tool is used, each constraint parameter is loaded to simulate the component forming process, the surface and crack condition is checked, the constraint parameters are corrected and perfected according to the output point cloud data and curves, meanwhile, the safe distance change under different production conditions can be simulated, the reasonable production process of the parts is determined, the speed and acceleration change in the rubber bag forming process are simulated, and the process parameters in the rubber bag forming process are accurately set by adopting the proper simulation environment are determined. Wherein the process parameters include: process allowance, selection of the position of the positioning lug, the size of the positioning holes, and the angles and relative positions among the holes.
The beneficial effects of the invention are as follows: (1) According to the simulation result of Marc software, for forming a long and narrow part with a larger radian, two lugs are respectively added at the two ends and the middle, and two pin positioning holes are added on each lug, so that the phenomenon that the part is pulled in the hydroforming and the subsequent trimming process can be effectively avoided, manual trimming of workers is reduced, scrapping caused by serious part deformation is reduced, and the production efficiency is improved. (2) And (3) comparing the shape template with the web surface of the part, marking out the lug of the part, cutting off the lug according to the marked line when appropriate, and filing appropriately after cutting off. The forming and appearance of the parts are not affected. (3) And the acceleration and the speed of rubber bag forming are simulated by adopting MARC simulation software, so that the manual shape correction of workers is reduced, and the surface quality of a product is improved. (4) The production efficiency of the frame-edge parts is improved, the self-processing capacity is improved, and the requirement of mass and fast-paced production rate is met.
Drawings
FIG. 1 is a block diagram of a positioning tab;
in the figure: 1, positioning holes; 2, positioning the lug along with the shape; 3 dip position 3.
Detailed Description
The present invention is further described below.
The invention mainly uses simulation data of simulation software to determine the positions of the positioning lugs, the arrangement of the positioning holes, the sizes of the positioning holes, the addition of process allowance and the like, and a specific tire is not explained here.
A finite element model for preventing movement during forming of a part comprises a web surface of the part, a positioning lug 2 and a positioning hole 1. The parts are airplane frame edge parts, basically have long and narrow arc structures, large radian, long length, narrow web surface and sunken flanging belts, and are basically similar in forming mode. The part is an aircraft frame flange-like part for the mounting of an aircraft skeleton structure, the structure of which is of great importance for the whole aircraft assembly.
The web surface of the part is arc-shaped, the web surface is narrow, the flanging belt is sunken, and the sunken position 33 of the web surface is added with a margin of 1 mm. Rectangular positioning lugs 2 with the size of 20mm multiplied by 10mm are respectively arranged at the two ends and the middle position of the web surface of the part, and the size of the positioning lugs 2 is determined according to the size of the part; each positioning lug 2 is provided with two positioning holes 1, the two positioning holes 1 are on the same straight line, and an angle of 45 degrees is formed between the two positioning holes 1 and the bottom edge of the positioning lug 2, so that firm and reliable positioning is ensured; wherein, the locating holes 1 on the locating lugs 2 at the two sides and above are close to the web sinking position 3, so that the dragging deformation, dislocation, inaccurate locating and torsional deformation of the part during the forming on the rubber bag hydraulic press are avoided. The form template is used to draw the last edge line on the part for subsequent workers to cut the tab according to the drawn edge line.
A method of preventing movement during part forming comprising the steps of:
1) Firstly, milling the unfolding shape of a part according to a two-dimensional unfolding data set with the process allowance, checking the surface quality of the unfolding material, and determining whether the surface quality is qualified; if cracks or large pits exist, the surface quality is unqualified, the next forming process cannot be performed, and the reprocessing is needed to avoid subsequent cracks.
2) Confirm the size of the positioning hole 1 and the position of the positioning lug 2
The size of the positioning hole 1 is determined according to the width degree of the web surface of the part, and the positioning hole 1 is larger as the part is narrower and longer, so that the phenomenon that the part is pulled during hydroforming and subsequent manual trimming is avoided. The pin positioning hole 1 with the length of 5.2mm is selected for the part, so that the positioning requirement of the part can be met, and the phenomenon that the part is pulled during hydroforming and subsequent manual trimming can be avoided.
Each positioning lug 2 is provided with two positioning holes 1, the two positioning holes 1 are on the same straight line, and an angle of 45 degrees is formed between the two positioning holes 1 and the bottom edge of the lug, so that firm and reliable positioning is ensured; wherein, the locating holes 1 on the locating lugs 2 at the two sides and above are close to the web sinking position 3, so that the dragging deformation, dislocation, inaccurate locating and torsional deformation of the part during the forming on the rubber bag hydraulic press are avoided.
3) Mounting and positioning lugs 2: two ends and the middle position of the web surface of the part are respectively provided with a rectangular positioning lug 2.
4) The processing technology comprises the following steps: firstly, judging whether a process allowance is added at the convex bent edge of the part, and if not, adding the part by a process staff; if the process allowance is added, the process allowance of 1mm is added to the sinking position 3 of the part, scribing is carried out according to the tire line after the forming is finished, and the redundant part is cut off, so that the requirement is met after the sinking position is formed.
The method comprises the steps of hydraulic forming, wherein the radian of a part is large, if the design is designed to give a margin for the severe tension of an arc-shaped bent edge outer edge material, the convex bent edge direction of the part does not need to be additionally provided with the margin, if the design is not designed to give the margin for the convex bent edge direction, a craftsman is required to add 1mm margin on one side of the convex bent edge, the material receiving of a sinking part is serious, the phenomenon of material shortage and meat shortage easily occurs, the design generally does not consider the process margin of the sinking part, and therefore, the margin of 1mm is required to be specially added at the sinking part, and after the forming is finished, the blank is drawn according to a tire line, and the redundant part is cut. The addition of the allowance is needed to give specific numerical values according to the simulation result, and an accurate process allowance is of great importance to the part forming, so that the product scrapping caused by meat deficiency can be reduced, trimming and filing caused by overlarge addition of the process allowance can be avoided, and the process allowance of 1mm is added according to the output result of Marc simulation software and the field experience of technicians, so that the part can be ensured to meet the digital-analog requirement after the part forming is finished.
The parts listed by the invention are currently applied to the assembly of the frame edge parts of various types of aircrafts, the field feedback service condition is good, the frame edge parts with larger radian can be formed or calibrated under different conditions by using the device with the shape-following long and narrow positioning lugs 2 in the production of similar parts of various types of aircrafts, and the field production requirement is fully met.
Claims (2)
1. The finite element model for preventing the movement of the part during forming is characterized by comprising a web surface of the part, a positioning lug and a positioning hole along with the shape; the parts are airplane frame-edge parts;
the parts are arc-shaped, the web surface is narrow, the flanging belt is sunken, and the sunken position of the web surface is added with a margin of 1 mm;
two ends and the middle position of the web surface of the part are respectively provided with a rectangular positioning lug, and the size of the positioning lug is determined according to the size of the part;
each positioning lug is provided with two positioning holes, the two positioning holes are positioned on the same straight line, and an angle of 45 degrees is formed between the two positioning holes and the bottom edge of the positioning lug, so that firm and reliable positioning is ensured; wherein, the locating holes on the locating lugs on the two sides and above are close to the sinking position of the web surface, so that the pulling deformation, dislocation, inaccurate locating and torsional deformation of the part during the forming on the rubber bag hydraulic press are avoided.
2. A method of preventing movement during forming of a part, characterized by the steps of:
1) Milling the unfolding shape of the part according to the two-dimensional unfolding data set with the process allowance, checking the surface quality of the unfolding material, and determining whether the surface quality is qualified; if the crack exists, the surface quality is unqualified, the next forming process can not be performed, and reprocessing is needed to avoid the subsequent crack;
2) Confirm the size of locating hole and its position in locating the lug:
the size of the positioning hole is determined according to the width degree of the web surface of the part, and the positioning hole is larger as the part is narrower and longer, so that the phenomenon of pulling of the part during hydroforming and subsequent manual trimming is avoided;
two positioning holes are formed in each positioning lug, the two positioning holes are positioned on the same straight line, and an angle of 45 degrees is formed between the two positioning holes and the bottom edge of each lug, so that firm and reliable positioning is ensured; wherein, the positioning holes on the positioning lugs on the two sides and positioned above are close to the sinking position of the web surface, so that the dragging deformation, dislocation, inaccurate positioning and torsional deformation of the part during the forming on the rubber bag hydraulic press are avoided;
3) Installing and positioning lugs: two ends and the middle position of the web surface of the part are respectively provided with a rectangular positioning lug;
4) The processing technology comprises the following steps: judging whether the process allowance is added at the convex bent edge of the part, and if the process allowance is not added, supplementing the process allowance; if the process allowance is added, the sinking position of the part needs to be additionally added with the process allowance of 1mm, and the requirement is met after the sinking position is formed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710466108.3A CN107085649B (en) | 2017-06-19 | 2017-06-19 | Finite element model and method for preventing movement during part forming |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710466108.3A CN107085649B (en) | 2017-06-19 | 2017-06-19 | Finite element model and method for preventing movement during part forming |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107085649A CN107085649A (en) | 2017-08-22 |
| CN107085649B true CN107085649B (en) | 2023-10-17 |
Family
ID=59607123
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710466108.3A Active CN107085649B (en) | 2017-06-19 | 2017-06-19 | Finite element model and method for preventing movement during part forming |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107085649B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108453149A (en) * | 2018-05-15 | 2018-08-28 | 江阴市博汇机械成套设备有限公司 | A kind of shaping tooling of large-size thin-walled cylinder body |
| CN114260650B (en) * | 2021-12-17 | 2023-11-03 | 江西洪都航空工业集团有限责任公司 | Sheet metal forming method for airplane homodromous bent narrow-long-mouth part |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101702185A (en) * | 2009-11-05 | 2010-05-05 | 西北工业大学 | Method for designing workpiece model for manufacturing aircraft sheet metal components |
| CN104200037A (en) * | 2014-09-15 | 2014-12-10 | 沈阳飞机工业（集团）有限公司 | Method for designing forming dies for low-double-curvature sheet metal parts |
| CN207148836U (en) * | 2017-06-19 | 2018-03-27 | 沈阳飞机工业（集团）有限公司 | A kind of FEM model for preventing from moving during part forming |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2520992B1 (en) * | 2011-05-02 | 2014-04-16 | Autoform Engineering GmbH | Method and computer system for characterizing a sheet metal part |
-
2017
- 2017-06-19 CN CN201710466108.3A patent/CN107085649B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101702185A (en) * | 2009-11-05 | 2010-05-05 | 西北工业大学 | Method for designing workpiece model for manufacturing aircraft sheet metal components |
| CN104200037A (en) * | 2014-09-15 | 2014-12-10 | 沈阳飞机工业（集团）有限公司 | Method for designing forming dies for low-double-curvature sheet metal parts |
| CN207148836U (en) * | 2017-06-19 | 2018-03-27 | 沈阳飞机工业（集团）有限公司 | A kind of FEM model for preventing from moving during part forming |
Non-Patent Citations (2)
| Title |
|---|
| 典型铝合金型材零件拉弯成形工艺的数值模拟与实验研究;杜建宁 等;锻压技术;第40卷(第4期);全文 * |
| 飞机铝合金双曲度蒙皮充液成形的数值模拟与试验;王玲 等;锻压技术;第42卷(第6期);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107085649A (en) | 2017-08-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104289748B (en) | A kind of large thin-wall covering adaptively equal wall thickness milling system and its processing method | |
| CN107085649B (en) | Finite element model and method for preventing movement during part forming | |
| CN107999640B (en) | Vehicle exterior cladding element model compensatation method | |
| CN108941321A (en) | A kind of stamping die production method of beam type component | |
| CN107030208B (en) | A kind of processing method of trimming and piercing die class mold | |
| CN104439914B (en) | Manufacturing method of S-shaped beam | |
| CN104307952B (en) | Curved steel plate forming method and curved steel plate forming equipment | |
| CN104014633B (en) | A kind of analogy method of removal bar core defect based on limited element analysis technique and the hole-punching method based on this analogy method | |
| CN106709148B (en) | Finite element simulation method for roll bending-milling process of large-size thin-walled part with step | |
| CN204672840U (en) | A kind of bender is with to line calibrating installation | |
| CN205290238U (en) | Electric car body skirtboard welding jig | |
| CN106001311A (en) | Forming device and method suitable for small-height flanged part | |
| CN104097196B (en) | A kind of projection scribble method for large-scale diesel engine support | |
| CN205218547U (en) | A position adjustment device for cambered surface puncher | |
| CN207148836U (en) | A kind of FEM model for preventing from moving during part forming | |
| CN106737275B (en) | 737CL type aircraft large-wing rear beam upper edge strip repairing, cutting and positioning tool and method | |
| CN111560614B (en) | Combined chemical milling sample plate and processing method thereof | |
| CN205096284U (en) | Automatic plastic frock of door sash face | |
| CN205988994U (en) | A kind of gusset mould for molding special-shaped part | |
| CN105403116A (en) | Detection sample plate for relief grinding allowance of runner weld seam circular bead | |
| CN206241557U (en) | A kind of crossbeam group mounted welder | |
| CN206065240U (en) | Electromagnetic valve armature and push rod riveted structure and die | |
| CN215657318U (en) | Auxiliary device for punching side wall of airplane sheet metal cover part | |
| CN218066270U (en) | Aircraft skin radian comparison tool | |
| CN218398091U (en) | Fitting and marking tool matched with part boundary |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |