Paint

Post on 01-Nov-2014

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WHAT IS PAINTPaint is the homogenous mixture of Resin, solvent pigments & additivites RESIN: It is the basic solid content in the paint. Resin is need for - Flow -Body appearance -Film formation -Pigment binding -cross linking etc.. SOLVENT: Solvent the volatile material . It mixes with paint to viscosity Settings and other properties.It need for -Reducing viscosity -change speed of dry/flashoff PIGMENTS: Pigments give the shade of the colour to the paint Aluminium flakes for metallic finishes, Mica based.

ADDITIVES: Additives added in paint small quantities to improve certain specific characteristics like UV absorbers- Durability Flow addivites- Leveling Anti settling agents Driers & catalyst. PAINTING Painting basically done to give good apperance, corrosion resistance & prevent From natural Causes like UV, Salt content , Acid content etc.. After painting process the following properties needed to check -Adhesion -Gloss -DOI -Colour -Orange peel - Hardness etc..

WBS PT/ ED

ED OVEN ED BUFFER

SEALER LINE 1 SEALER LINE 2

UBS UBS BOOTH OVEN

PRIMER SANDING

PRIMER BUFFER

PRIMER PRIMER OVEN BOOTH OFF LINE

UBS ED SANDING BUFFER

TOP COAT 1 TOP COAT 1 TOP COAT INITIAL OVEN BUFFER INSPECTION TOP COAT 2 TOP COAT 2 HRS T/C OVEN OK BLACK FINAL POLISHING LINE 1 PBS LINE TAPE POLISHING LINE 2 NOT OK SPOT REPAIR 1

ASSEMBLYSPOT REPAIR 2

PRETREATMENT:Pretreatment is the process to remove all contamination from the surface. To make the surface reactive. Pre-treatment mainly done to give corrosion resistance.

Pre treatment Process flow:ED BATH (DIP) UF-1 (SPRAY) UF-2 (DIP) UF-3 (SPRAY) RCDI-1 (SPRAY) RCDI-3 (SPRAY)

FRESH DI (SPRAY)

HOT WATER RINSE -1(11KL) SPRAY:To remove the oil contamination and any other foreign materials in the incoming Body from body shop. It improves the degreasing process& reduce degreasing Solution contamination by removing body welding chip, grinding, sanding chips . Control parameters: PH - >10.0 spray pressure- 4-6 kg/cm2 Temperature- 40- 50*c Liquid level from top- 200 mm Spray volume- 4000 l/ min. max

HOT WATER RINSE -2 (11KL)SPRAY:Control parameters : spray pressure- 1.0- 2.0 kg/cm2 Liquid level from top- 100 mm Spray volume- 1950 l/ min. max pump electric current- 14- 15A

DEGREASING (11KL) SPRAY:Degreasing process used to improve Phosphate film performance & paint Adhesion power, by removing grease, oil & other foreign particles Control parameters: Alkalinity point- 25- 30 CHEMICAL NAME: oil content- 10.0 Spray pressure- 1.5 2.5kg/cm2 Exit spray volume- 1600 l/hr

PHOSPHATING:To increase corrosion protection, durability of car by providing a solid Formation for adhesion of subsequent coat. It act as a non conducting bond between Paint & metal surface. Control parameters: Total acidity point- 22-25 Free acidity 1.0 - 1.4 zinc content- 1.0- 1.5g/lit coating weight- 1.8 3.0 g/m2 Temperature- 45 50*c

WATER RINSE- 4 SPRAY:To remove carry over of phosphating solution & to provide durability & uniform Dense of zinc phosphate layer. Total acidity< 1.5 mist spray volume- 1600l/hr spray pressure- 1.0 2.0 kg/cm2 Temperature- ambient spray volume- 1900l/min.max liquid level from top- 12-13 A

WATER RINSE -5 (DIP):Total acidity < 0.5 circul. Pressure- 1.5- 2.5 kg/cm2 Temperature- ambient mist spray volume- 1600l/hr

DI RINSE 1, 2 (SPRAY) :To prevent mineral oil contamination into the ED tank & provide uniformly Conductive surface of ED application. Control parameters: circulation pressure- 1.5 2.5 kg/cm2 liquid level from top- 100 150mm mist spray volume- 1600l/hr spray volume- 1900l/hr

DI ENTRY SPRAY:To improve ED application quality by preventing the body from semi drying& Complete drying. Body should be in full wet condition before entry in to the ED tank. Spray volume- 1000- 1600l/hr

ED TANK DIP (250 KL):To increase corrosion protection & durability of car by coating through electro Chemical process in order to provide a smooth uniform coating. It has the best ability To coat inner surface. ED process parameters the impact coating appereance, quality & Performance on all substrates. Control parameters for ED : % NVM 18- 23 PH at 25*c 5.5- 5.9 bath temperature- 28-32*c pump pressure- main ciru.- 2-3 bar cooling circulation- 2-3 bar UF module pump- 4-5 bar Rectifier voltage & current inlet bus bar- 0- 170V (max. 2000A) Main bus bar- 180- 270 V (max. 2000A) % solvent 0- 0.8 anolyte flow rate- 100l/hr/cell permeate PH at 25*c- 5- 5.9 permeate solids - 1.5%

UF -1 (ULTRA FILTRATION):The purpose is to recover carry over paint from carbody, UF rinse will prevent The body from paint dry defects and provide smooth , uniform finish. Control parameters: %NVM -