1、 Printed Copies are Uncontrolled Page 1 of 23 Standard Number UC800 Issue Date: January 2007 European Manufacturing Standard Rev: 20070115 PAINT PROCESSING OF CAR AND VAN BODIES 1.0 PURPOSE: This procedure describes the general process and controls for the pre-treatment, electrocoating, priming, pai
2、nting and corrosion protection of passenger car and van bodies within Paint and Final Assembly Engineering. It must be used in conjunction with GSPAS (where applicable) and the individual Model Paint Process Sheets to provide full processing details. The designator SC indicates that this property is
3、 a significant characteristic which effects vehicle capability to satisfy corrosion warranty requirements and which requires special controls. 1.1 Procedure The procedures described are as follows:- Materials Section 2 Pre-Treatment and Phosphating Section 3 Electrocoating Section 4 Sealing and Body
4、 Protection Section 5 Primer Surfacer Application Section 6 Enamel Application Section 7 Paintshop Panel Repairs Section 8 Complete Body Paintshop Repairs Section 9 Wax Protection Section 10 Garage Paint Repairs Section 11 Baking Cycles Section 12 Film Thickness Requirements Section 13 Quality and M
5、anufacturing Targets Section 14 Abbreviations and References Appendix A Printed Copies are Uncontrolled Page 2 of 23 Standard Number UC800 Issue Date: January 2007 European Manufacturing Standard Rev: 20070115 2 MATERIALS: 2.1 All production, non-production and post-production materials, including n
6、ecessary additives must be approved in accordance with procedure FAP 03-132. 2.2 Only paint materials, which have been approved in accordance with Vehicle Operations Operating Procedure VOP PTG-205 and have undergone a suitable production line trial can be used in paint processing operations. 2.3 Al
7、l materials must have full C2 clearance status from the GMAP computer system and have been approved for use in their specific applications and locations by the responsible Plant Medical, Safety, Fire and Environmental Officers. 2.4 A control plan for ongoing production verification is required to as
8、sure consistent processing of materials. Appropriate statistical tools such as Statistical Process Control must be used in the analysis of process and product data. 2.5 All Paintshop production and non-production materials shall be free of crater inducing materials when tested in accordance with FLT
9、M BI 125-01. 3 PRE-TREATMENT AND PHOSPHATING 3.1 Preliminary Clean-up - BIW Area Bodies shall be free from foreign material. Exterior surfaces should be solvent wiped to remove residual sealants, grease, oil, chalk and stamping marks etc. 3.2 Treatment of Areas Discoloured by Heat - BIW Operations A
10、ny discolouration caused by welding or brazing on the outer or critical customer visible interior surfaces shall be removed by sanding machine. Final sanding must always be completed with a minimum of 400grit. The disking of protective coated steels, such as zinc coated, and galvannealed steel must
11、be avoided at all cost, as not to adversely affect the corrosion protection properties of this material. 3.3 Preliminary Cleaning and Fitting of Slave Tooling The complete body in white surface must be cleaned by an automated process to ensure the absence of oil or alkaline residues, fingerprints, c
12、orrosion, weld spatter, mold release agents, dirt and any foreign material. This will avoid cross contamination of the phosphate system and further downstream processes. The approved and released cleaning material, as detailed in the Model Paint Process Sheets (GSPAS) must be used. To allow satisfac
13、tory cleaning and Phosphating of enclosed areas all closures shall be retained in a partially open position by slave tools as depicted on the Model Paint Process Sheets. Printed Copies are Uncontrolled Page 3 of 23 Standard Number UC800 Issue Date: January 2007 European Manufacturing Standard Rev: 2
14、0070115 3.4 Phosphating Phosphating of bodies shall be carried out using an automatic spray, spray-dip or full dip system. All internal and external surfaces of Phosphated bodies must meet the requirements of specification WSS-M3P1-D (Performance, Phosphate Coating, Zinc). Phosphate coating weights
15、and specification references are described in Paragraph 13.1. 3.5 Phosphate Draining relevant Model Paint Process Sheets are to be followed. All over sanding, should be avoided, and sand through to metal must be avoided. Paper no coarser than 600 grit should be used for final sanding. Sanded through
16、 areas of finished bodies must meet Performance Specification WSS-M2P-180-A requirements. 5.0 SEALING AND BODY PROTECTION 5.1 Sealants, including caulking compound, plugs, adhesive tapes and NVH, shall be applied in line with relevant Model Paint Process Sheets and the Model Sealer Manual. Clean are
17、as should be masked with either mechanical or disposable masks. Any surface contamination must be removed by wiping with clean lint free cloths and/or an approved solvent 5.2 Under body coating material may be applied, either manually or automatically, to areas shown on individual Model Paint Proces
18、s Sheets. Clean areas should be masked with either mechanical or disposable masks. Any surface contamination must be removed by wiping with clean lint free cloths or spatulas. Printed Copies are Uncontrolled Page 5 of 23 Standard Number UC800 Issue Date: January 2007 European Manufacturing Standard
19、Rev: 20070115 5.3 Body skid mounting areas that are not coated with underbody material must be protected with an approved repair material prior to the underbody wax application. This may be achieved by brushing or spraying. Film thickness and specification requirements are detailed in the Model Pain
20、t Process Sheets and Model Sealer Manual reference Paragraph 13.3 5.4 Pre-gelling of the sealants and underbody coating is recommended to facilitate the removal of excess sealer and underbody coating overspray and also to prevent contamination of automatic ostrich feather machines. The baking cycle
21、is described in Paragraph 12.3 and 12.11. 6 PRIMER SURFACER APPLICATION 6.1 Cleaning of Electrocoat Primed Bodies Before entry into the Primer Spraybooth all exterior surfaces should be blown-off with dry oil-free deionised air (to standard ISO 8573 class 3) followed by, an automatic ostrich feather
22、 dusting machine with subsequent manual tack wipe using approved tack rags. 6.2 Application of Lower Body Stonechip Protective Stone chip protective primer should be applied automatically to the areas specified on relevant Model Paint Process Sheets and over coated wet on wet with a minimum of 20 pr
23、imer surfacer. Film thickness requirements are detailed in Paragraph 13.4. 6.3 Application of Primer Surfacer the first coat by electrostatic bells and the second coat electrostatically or pneumatically. For optimum usage and appearance 60 70 % of the film weight should be applied in the first coat
24、and 30 40 % in the second (however, this ratio should be optimised for individual colours). 1-minute flash-off between coats is recommended. 7.5.1 Before application of the solvent based Clearcoat, the water based Basecoat must be: flashed-off for 1 minute minimum Infra-red heated for 1 minute to 80
25、oC metal temp 2 minutes warm air drying at 80oC min metal temperature Cooled to 30o C object temperature Film thickness requirements are detailed in Paragraph 13.9 7.6 Clearcoat - Solvent Based For optimum efficiency and appearance paint application should ideally be in two coats using electrostatic
26、 bells. Each coat should apply approximately 50% of the film weight. For handspray or automatic operations a 1-minute flash-off is required between coats. Film thickness requirements are detailed in Paragraphs 13.11. 7.7 Booth Operating Conditions These must be optimised on the basis of meeting the
27、requirements of enamel specifications highlighted in section 13 and achieving quality and manufacturing objectives (paragraph 14.1). Booth control and application parameters should be within the limits agreed upon by the Material Supplier and Manufacturing Plant Engineering in order to achieve proce
28、ss capability. These shall be monitored by statistical process control techniques and stated in the production control plan. 7.8 Masking Any masking paper or foil should be removed before entry into the baking oven. Printed Copies are Uncontrolled Page 8 of 23 Standard Number UC800 Issue Date: Janua
29、ry 2007 European Manufacturing Standard Rev: 20070115 7.9 Baking of Water and Solvent Based Metallic/Solid Basecoats with Solvent Based Clearcoat A minimum of 3 minutes ambient flash-off time is required prior to stoving. Refer to section 12 for details on baking cycles. 7.10 Decorative Stonechip Pr
30、otection Mask areas to be sprayed according to the relevant Model Paint Process Sheets. Blow-off with compressed air to ISO 8573 class 3 and wipe areas to be painted with tack cloths. Spray areas with one coat of chip resistant primer to achieve the minimum film thickness as specified in Paragraph 1
31、3.5. Allow a minimum of 3 minutes flash-off from the exit of the last spraying zone. Bake in accordance with information detailed in section 12. Printed Copies are Uncontrolled Page 9 of 23 Standard Number UC800 Issue Date: January 2007 European Manufacturing Standard Rev: 20070115 8.0 PAINTSHOP PAN
32、EL REPAIRS The following procedures are recommended for the repair of painted bodies in the paintshop. 8.1 Repair by Polishing Minor defects such as scratches, dirt, etc. may in many cases be eliminated by machine polishing or by careful sanding with a minimum of 1200 grit paper and subsequent machi
33、ne polishing and buffing. 8.2 Polishing Procedure See individual Model Paint Process Sheets for details on polishing procedure. 8.3 Repair by Painting Paint defects that cannot be removed by polishing should be repaired as follows: Panel repairs to solid and base/clear metallic enamel colours shall
34、be locally damp-sanded with demineralised water and finished with a minimum of 1200 grit paper. Tack wipe and blow-off the area of the panel to be repainted. Ensure that the complete body is free from dirt and dust prior to entry to the booth. Pay particular attention to retention areas e.g.: drip r
35、ail, channels etc. to avoid any contamination occurring in the booth or oven. Panels adjacent to repairs should be masked. The outer surfaces to be repaired are sprayed with one or two coats of enamel to achieve film thickness. One minute flash-off time is required before each successive spraying ap
36、plication of basecoat clearcoat. Inside areas may be repaired with one coat, provided the minimum film thickness and appearance is achieved. Tapes and masking paper must be removed before baking. Allow a minimum flash-off of 3 minutes before entry into the oven. Baking is carried out in accordance w
37、ith the baking cycles detailed in section 12. The repair of defects with air drying repair paint is permitted only for inner surfaces, as per relevant Model Paint Process Sheets. 9.0 COMPLETE BODY REPAIRS THROUGH PAINT SHOP 9.1 When paint repairs are performed through the main Enamel Spraybooths, de
38、fective panels are prepared as per Paragraph 8.3., however no masking or scuff sanding on non-repair areas is required as all exterior surfaces will be re-painted. Bake in accordance with the baking cycles detailed in section 12. Printed Copies are Uncontrolled Page 10 of 23 Standard Number UC800 Is
39、sue Date: January 2007 European Manufacturing Standard Rev: 20070115 10.0 WAX PROTECTION The European Cavity Waxing Strategy applies to vehicles with conventional design at rocker panel, engine compartment and underbody. The relevant Model Paint Process Sheets specify the exact areas to be waxed. Th
40、ese process sheets are derived from the relevant Model Sealer Manual, which is the responsibility of the Model Corrosion Engineer. 10.1 Approved Wax Material Specifications are as follows: WSK-M7C93A Waterbased Material WSS-M21P35-A 0 Emission Material WSK-M7C79-A/A2 High Solid Solventbased Material
41、 (This material must not be used for 12 Year Perforation Warranty). 10.2 Warranty terms above 10 Years require Automatic/Robotic cavity wax application. Below 10 Years Warranty manual application is permitted. 10.3 Dry film thickness for specific material specification references are detailed in Par
42、agraph 13.14. 10.4 Drying cycles for all protective waxes are detailed in Paragraph 12.10. 11.0 GARAGE PAINT REPAIRS The procedure described below refers to the removal of paint defects and damage incurred following Trim Assembly Operations. 11.1 Repairs with Catalysed Enamels The remarks contained
43、in Paragraph 8.3 apply equally to the preparation for garage repair painting. However, for the baking of the repair paints, a completely assembled vehicle cannot be subjected to the specified high baking temps used in the paint shop. In order to achieve sufficient hardening of the enamels at tempera
44、tures compatible with completely assembled vehicles, it is necessary to use an approved acid catalysed, or 2K clearcoat material, as specified on the individual model paint process sheets. Acid catalysed basecoats may be used for repair of solvent based SVO or van solid colours. Catalysed enamels sh
45、ould be used within 24 hours of preparation. It is permissible to exceed this time (up to 120 hours) provided fresh catalysed material is added to that remaining at very regular intervals. All repairs must meet the performance requirements of WSS M2P180-A. NB: Ensure that all containers, pipelines,
46、hose fittings and filters to be used for storage and supply of catalysed enamel are resistant to acid catalyst material. 11.2 Enamel Application The areas to be repaired shall be sprayed with two separate coats of the appropriate catalysed enamel; or uncatalysed Basecoat metallic. Basecoat repairs s
47、hall be followed by two coats of the catalysed Clearcoat. Film thickness requirements are shown in section 13. Bake in accordance with the cycle in Paragraphs 12.8 10 minutes above 160oC Maximum metal temperature 190oC Maximum temperature of ambient air 205oC 12.2 Baking Cycle for Cathodic Electroco
48、at Coatings Minimum cycle metal temperature for high risk potential stone chip and corrosion areas: 10 minutes above 175oC Interior and other areas: 5 minutes above 165oC Maximum metal temperature 205oC Maximum temperature of ambient air 220oC N.B. For instances where plastic panels are used, check
49、the material specification for maximum operation temperature of the thermoplastic to ensure it can function at the temperatures specified above 12.3 Baking Cycle for Pre-Gelling of Sealers and PVC Underbody Coating Minimum cycle temperature; 5 minutes above 90oC Maximum metal temperature 130oC Maximum temperature of ambient air 180oC 12.4 Baking Cycle for Materials Applied in Solvent Based Primer Booth Minimum cycle metal temperature; 5 minutes
