How to measure automobile sheet metal tester

Author：Web　Source：Web　Date：2018-07-24 11:18:29　Sentiment：57

I. overview of automobile inspection tools:

Inspection fixture is short for online inspection fixture such as stamping parts and welding parts. It has the same meaning as the sample holder mentioned in other version documents. Inspection tool is a special testing tool according to the specific requirements of the buyer. The profile of the inspection tool must be processed according to the CAD data of the parts, which can reflect all the parameters of the parts and carry out qualitative detection of the parts. For some of the most important functional dimensions on the parts, we can also use the inspection tools for numerical detection. The tester should also have the function of measuring bracket, but when the function of on-line measuring function and measuring support function cannot be satisfied at the same time, the function of on-line measuring should be satisfied first.

Inspection design, manufacture and acceptance shall be based on product drawings and master models (or CAD data). When there is no master model (or CAD data) for the parts, the product drawings and samples approved by the buyer shall be taken as the basis.

Under the normal condition of frequency and good maintenance, the inspection tool should have the same service life as the corresponding rolling die and welding fixture.

Considerations before production of inspection tools (5 points) :

1. Parts and precision confirmation methods required for precision of finished products.

2. Importance of accuracy requirements and validation methods.

3. Consider the amount of deformation produced by the finished product in the process of stamping parts.

4. Use considerations (convenience, lightweight and fast).

5. The overall structure is firm but not deformed.

Iii. Introduction to inspection tools:

1. Purpose of use:

Check the shape, trimming, folding line and hole position of parts.

2. Materials used:

A. Profile (shape) surface: large and medium stamping parts: made of resinable materials (good surface and abrasion-resistant resin); Small stamping parts: aluminum alloy or steel or processed resin materials (good surface and abrasion-resistant resin); Check the sample and other: iron or resin.

1) resins -- resins with good surface and abrasion resistance, with sufficient strength after being strengthened by glass fiber. 2) steel. Small stamping parts: aluminum alloy

C. Reinforcing structure: the steel tube -- foot frame part is round, the outer diameter is more than 1cm, and the square pipe shape of the base is more than 25mm. After the completion of the steel tube structure, proper heat treatment should be given to eliminate internal stress.

D. Reference block: large and medium stamping parts: steel plates or steel plates with resin; Small stamping parts: aluminum alloy.

Coating: 3.

A. After the completion of the production of the inspection tool, the inspection tool body and foot frame shall be coated: check the distinction of the operation nature (the part of the body fixture) : zero contact surface: white; Clearance inspection surface: 3mm clearance (shape part) green; 1mm clearance surface (hole position) red; Non-inspection area: green.

B. Appearance coating: check the foot frame and body of the fixture to spray blue or customer requirements.

Iv. Production process of inspection tools:

A. production preparation:

1. After accepting the task, understand the process requirements, quality requirements and speed requirements of model manufacturing;

2. Understand the inventory of all kinds of raw materials needed for manufacturing the main model;

Know the equipment.

B. Review of drawings:

C. blanking:

1. Foam board is used for simple type surface, and the blank is taken by hand according to the drawing. 6-8mm is reserved for small working surface and 8-12mm is reserved for medium and large working surface.

2. According to the size of the product diagram, the complex surface shall lay down the blank materials and mark the coordinate lines. After the completion of nc machining, the developer shall check whether there is enough machining allowance for the type surface and contour according to the product diagram provided by the programmer.

D. Fillable resins: l-15, part a: white cement. Group b: red and brown cementitious, proportionally prepared; A: yilongyuan (2:1), jida (1:0.8) is stirred by agitator. Before dressing, knead again (increase density, reduce porosity). The compaction thickness of dressing is 30-40mm(including machining allowance).

E. production of supporting framework:

1. For small main model face tubes, paint 12; for large and medium sized ones, paint 16 steel tubes should be arranged according to the shape. The mesh spacing should be 150-200mm, and 30-40mm should be left from the periphery.

2. The base frame is connected with steel tube or hollow square steel at a 45-degree Angle, and the tolerance of parallelism and verticality between adjacent angles is + / 2mm, the transverse pitch is 350-400mm, and the longitudinal pitch is 450-500mm.

3. The two end faces of the support tube are compressed and welded together with the support surface and then welded together. Meanwhile, the 80 * 80 * 10mm reference frame and lifting device are welded together. After the aging is finished, the welding place shall be polished by grinding machine and the excess welding points shall be leveled.

F. The connection between the frame and the machinable resin of the mold surface: the adhesive material is prepared in proportion (the same type fabric as required by l-15), and the gap between the mold surface pipe and the mold surface fabric is filled after the mixing is even, and the mold surface closing pipe is buried in the adhesive material for a thickness of 10-15mm.

G. Fabrication of false datum: 30 * 50 * 25mm boards or wooden blocks are uniformly bonded to the bottom frame and leveled with a height ruler and a flat shovel (large CNC milling and milling) with a thickness of 20mm from square steel.

1. Black paste of material l-10 group a and light yellow liquid of group b. A: b = 100:15. On the measuring scale platform, according to the benchmark position, the benchmark slot of 100x100x25 was enclosed with the reference block and foam plate, and the demoulding agent was painted. Then, the benchmark frame of the main model was found to be correct, fell into the square slot and sealed. 2. Mix the l-10 reference material (group a should be fully stirred before use due to precipitation) in proportion and pour it into the square groove. After curing for 24-48 hours, mark X, Y, Z reference value and figure number and send it to CNC milling.

I. precision repair of type surface: after the completion of nc machining, test according to the inspection point provided by the electronic calculation against the product diagram, and confirm that the size basically meets the requirements. The precision repair can only be carried out after the data are consistent with the product.

J. Surface treatment: after finishing the molding surface, use epoxy resin for surface treatment, so as to fill the surface pinholes and add the surface strength. The epoxy resin should be thin and even.

K. Paint and label: the metal frame shall be painted according to the color required by the user, and the label and coordinate plate shall be printed out. The 100-200 coordinate grid line shall be drawn, and the hole position line shall be drawn, the border line shall be repaired and the black mark line shall be painted.