3.1.11 Student Book © 2004 Propane Education & Research CouncilPage 1 3.1.11 Applying Protective Coatings to Storage Containers ASME tanks require proper

3.1.11 Student Book © 2004 Propane Education & Research Council Page 1

3.1.11

Applying Protective Coatings to Storage

Containers

ASME tanks require proper protective coatings to protect them against corrosion and excessive pressure in hot weather. Each service application has characteristic environmental factors that act on container coatings.

In this module you will identify:

(1) Safety precautions when painting propane storage containers

(2) Procedures for painting tanks and cylinders

(3) Properties of ASME tank coatings


Safety Precautions When Painting ASME Tanks

• Never attempt to clean or paint a leaking propane container.

• All solvents, paints and paint thinners are flammable to some extent. Always keep a properly inspected B:C rated fire extinguisher nearby when using solvents. Store these materials in suitable ventilated and labeled metal cabinets.

• Any electrical tools used in cleaning or painting operations should be three-wire (grounded) or double insulated.

• Any electrical extension cords should be three-wire (grounded) cords, and not have any breaks in the insulation.

• Avoid placing any power tools or extension cords in moist areas or puddles of water. Always use a Ground Fault Circuit Interrupter (GFCI) in conjunction with power equipment.



• When using sandblasters, power sanders, or spray painting equipment, be sure to wear proper breathing apparatus, safety goggles, and appropriate safety gloves and work clothing or hoods.

• When spray painting, avoid over-spray on container valves, accessories, or other equipment.

• At customer locations, use a brush or roller to avoid possible damage to property that can occur with wind-carried paint spray.

• In order to reduce the possibility of a fire, use regulated air pressure—never LP-Gas pressure— to supply paint spraying equipment.



• Paint and coating manufacturers provide instructions on the safe use and handling of their products. Before using them, be sure to read and understand any manufacturer's instructions or procedures. Read all parts of the manufacturer’s Material Safety Data Sheet (MSDS) for each product (solvents, primers, paints, or catalysts) before use.

Never pour paint, solvents, or their waste products down sewer drains or on the ground. Read and follow company procedures for the use, cleaning and storage of respirators if they are required for a particular job or paint product application.

3.1.11 Student Book © 2004 Propane Education & Research Council Pages 2 & 3

Procedures for Painting ASME Tanks

Step 1: Prepare the Surface for Painting.

• Remove Dirt, Mud, and Salt Deposits.

• Remove Oil, Grease, and Chemicals.

• Remove Mildew and Fungus.

• Remove Flaking or Chipping Paint. During this process, check for leaks, and if one is found, repair it. If not a valve or fitting leak, tag the tank for removal from service and/or repair by the manufacturer or an authorized ASME repair facility.

• Remove Rust.

• Sand Rough Surfaces and Wipe Clean.



Figure 1. Commercial Sand BlasterPreparing Bulk Storage Tank for Re-Coating



Step 2: If Necessary, Select and Apply a Metal Primer and Special Coating.

• Selecting Metal Primers. (See the chart in Figure 2, page 5.)

• Applying Metal Primers. (See the notes listed under this topic for detailed guidelines, page 6.)

• Applying Special Coatings.



Step 3: Select and Apply a Finish Coat.

• Select a Finish Coat. Check manufacturer's instructions to be sure

the finish coat is compatible with the primer. Never paint an aboveground container black

or any other dark color; use light-reflective colors only.

• Applying Finish Coats.



Step 4: Determine the Required Markings for the Container

After painting, mark the required federal, state, and local codes as well as any company requirements.

• General markings— these may include company advertising, precautionary or procedural markings.

• NFPA required markings— depending on tank capacity and service application.



Figure 3. Tank and Cylinder Requiring Markings on Vapor and Liquid Openings


Properties of ASME Underground Tank Coatings

Underground protective tank coatings are formulated to have low electrical conductive properties, similar to materials used to insulate electrical wiring.

Tank coatings for underground tanks should be selected based on tank manufacturer’s recommendations or on the advice of a qualified professional corrosion engineer.

Corrosion on an underground tank will be concentrated at any point of damage to its protective coating, such as places where surface preparation is inadequate and coating does not adhere to the metal, or where the coating is damaged by handling resulting from chains or straps used to secure the tank during transportation or friction contact with vehicle surfaces.

3.1.11 Student Book © 2004 Propane Education & Research Council Pages 11 - 13

Time to See If You Got the Key Points of This Module…

• Complete the Review on pages 11 & 12.

• See if you are ready for the Certification Exam by checking off the performance criteria on page 13.

Documents

3.1.11 Student Book © 2004 Propane Education & Research CouncilPage 1 3.1.11 Applying Protective Coatings to Storage Containers ASME tanks require proper