HAZARDS OF MANUFACTURING PROCESSES

FINISHING OPERATIONS

BASIC PROCESS IN MANUFACTURE OF MANY PRODUCTS.  MUST ENSURE PROTECTION FROM SPRAYING OF FLAMMABLE AND COMBUSTIBLE MATERIALS, OVERSPRAY, FLAMMABLE VAPORS, DIP TANKS, POWDER COATINGS.

FIRES IN THESE FACILITIES DEVELOP VERY QUICKLY, HAVE HIGH HEAT RELEASE RATES, AND PRODUCE LARGE VOLUMES OF TOXIC SMOKE.

THREE TYPES OF FINISHING OPERATIONS:

1.  LIQUID / SPRAY COATING

1. AIR SPRAY GUN - HIGH P.S.I. BREAKS FLUID INTO FINE MIST.
2. AIRLESS SPRAY GUN - GENERATES SPRAY BY HYDRAULIC MEANS (300 - 3,000 P.S.I.)
3. ROTATING ATOMIZER - 6 - 12 INCHES.  DISC WITH FLUID ON SURFACE.  ROTATES AT 60,000 R.P.M. ANS SPRAYS 360° PATTERN, USED ELECTROSTATICALLY.

HAZARDS

• CHECK VENTILATION FROM OVERSRAY
• FLAMMABLE / COMBUSTIBLE LIQUID QUANTITY SHOULD BE LIMITED TO ONE DAY SUPPLY.
• ELIMINATE POTENTIAL FOR STATIC ELECTRICITY (BONDING / GROUNDING)
• MAINTENANCE PROGRAM FOR CLEAN UP OF ROUTINE OVERSPRAY BUILDUP.
• SKILLED, TRAINED, PROTECTED OPERATORS

2.  POWDER COATING

• POWDER IS SUSPENDED IN AIR, THEN CHARGED ELECTROSTATICALLY FROM A dc POWER SUPPLY (60 - 120 Kv).  THE POWDER IS DIRECTED AT THE WORKPIECE AND HELD IN PLACE BY ELECTROSTATIC FORCES.  POWDER IS FORMED INTO COATING AS IT MELTS THROUGH AN OVEN.

HAZARDS

• POWDER COATINGS ARE FLAMMABLE AND A CLOUD OF POWDER IS POTENTIALLY EXPLOSIVE.
• PROPERLY OPERATING DUST COLLECTORS.
• ADEQUATE VENTILATION AND INTERLOCK BETWEEN FAN AND APPLICATION.

3.  OTHER COATING APPLICATIONS

1. DIP TANKS.  LIQUID CONTAINERS OF VARIOUS SIZE AND SHAPE DESIGNED FOR A SPECIFIC PROCESS.
2. FLOW COATING.  COATING MATERIAL IS APPLIED FROM NOZZLES IN AN UN ATOMIZED STATE.  EXCESS FLUID IS COLLECTED IN A TROUGH, RETURNED TO RESERVOIR, AND RECIRCULATED.
3. CURTAIN COATING.  APPLICATION TO FLAT OR SLIGHTLY CURVED WORKPIECE'S, COATING IS PUMPED TO A HEAD, OVERFLOWS A DAM, FORMS A CONTINUOUS STREAM ON WORKPIECE, AND RECIRCULATES.
4. ROLL COATING.  COATING MATERIAL IS APPLIED BY DIRECT CONTACT WITH LIQUID COATED ROLLERS.

HAZARDS

• ADEQUATE VENTILATION
• TANKS OF MORE THAN 150 GALLONS SHOULD HAVE OVERFLOW PROTECTION
• CONVEYOR OPERATIONS

INSPECTION

• GOOD HOUSEKEEPING IS IMPERATIVE TO SAFETY AND OPERATION
• OPERATION PERSONNEL SHOULD RECEIVE HEALTH AND SAFETY INSTRUCTION
• REPORT ON CONDITION OF EQUIPMENT, VENTILATION, GROUNDING / BONDING, EXTINGUISHING EQUIPMENT, ETC.

       
INDEX HEAT-UTILIZATION EQUIPMENT

FPT 102 - Fire Prevention and Inspection // Instructor: Kevin M. Kolb        Slide #2