The chime is the flat plate at the bottom of a welded vertical oil storage tank. Water infiltration is a general problem for storage tanks, as water penetrates below the floor plate, creating a corrosive environment. Due to movements and weathering, regular sealants have not been successful. This specification describes a flexible system for new or existing storage tanks to prevent water infiltration and corrosion problems.

In general, the floor plate of the tank is resting on a concrete ring. A gap is common between the concrete ring and floor plate, as movement is expected during filling. If the chime area is not sealed, water can penetrate between the floor plate and the sand bed, creating a corrosive environment. Important features of the waterproofing system described in this specification are flexibility, durability and strong adhesive properties.

Materials Required

1. Amcor EZ Wrap. Consists of: pressure sensitive adhesive with reinforcement and covered with a polyester cloth or covered with another release liner (double sided). Packaged in rolls 4 inch by 24 feet, 30 mils. Color gray.

2. Amcorr EZ Paste. Available in cartridges 10 oz ( 310 ml) or 1 liter (1.06 quarts).

3. Applicator gun. High trust ratio bulk applicator gun, hand, pneumatic or electric. Used to apply EZ Paste.

4. Air compressor, used for drying surfaces.

5. Seam roller, used to apply EZ Wrap.

Application

Pressure wash to clean surfaces.	Dry surfaces with high pressure air.
Apply EZ Paste with an applicator gun.	Apply EZ Wrap with a seam roller.

1. Remove dust, dirt and any corrosion. The coating at the tank shell must be according to internal specifications.

2. Clean the concrete ring and chime area of the floor plate by regular pressure wash (in between chime and concrete as well). This is 3 inches on concrete and the complete chime area.

3. Dry the complete area (including in between chime area and concrete ring) with high pressure air (air compressor).

4. Apply Amcorr EZ Paste with the applicator gun by squirting the material between the chime and concrete ring. Fill the void 1 inch deep. To get a good fill, press the flexible nozzle half an inch in the void. Go around the tank completely. Angle the material by a putty knife at the transition between the concrete ring and chime.

5. Apply Amcorr EZ Wrap. Start on the chime and cover the chime completely (start shell/floorplate corner). Overlap on the concrete ring should be at least 2 inches. Remove the release liner and unroll the roll lengthwise, pressing the EZ Wrap down well with the seam roller.

6. Paint the EZ Wrap for esthetics and to protect it from any solvent chemicals such as jet fuel, diesel fuel, gasoline or other. A chemical resistance chart is available upon request.

7. Inspect your work. Check if the EZ Wrap shows good adhesion at the concrete ring and the steel. This can be done by peeling the edges of the tape and see if the material bonds completely. Complete adhesion takes place after a while, so a time slot of half an hour after application should be taken into account. The edge of the tape should end exactly at the corner of the shell and floor plate. A minimum overlap of 2 inches should be achieved on the concrete ring. The amount Amcorr EZ Paste should reflect the average calculated amount and not less. A cut-out can be made of the EZ Wrap to check the fill. 1 inch deep should be the minimum. After the cut-out,  a patch should be made with 1 inch overlap on each side.

Application Notes

The surface temperature of the concrete ring and shell should be above 40°F to obtain quick adhesion. To achieve quick adhesion in colder temperatures, a hot air blower can be used. the materials can also be preheated to 65°F or higher, but should not exceed 185°F.

When humidity is high or the surfaces get wet, the surfaces need to be dried. Concrete has a tendency to stay wet.

For safety, wear safety clothing and goggles during application. The described materials are non-toxic. Please see the MSDS for Amcorr EZ Wrap and Amcorr EZ Paste.