Masking tape: Masking tape absorbs water. Once masking tape becomes saturated, the flange will begin to rust. Masking tape takes longer to dry out, water contact time increases as does the rate of flange damage. Masking tape is easily found in the field on most construction sites as most painters use this tape for MASKING. Masking tape and preservation should not be used in the same sentence. Vinyl/polyethylene tape: While vinyl and polyethylene tape are more UV resistant, water/moisture still seep under the tape causing rusting/pitting. Duct Tape: Duct tape: Duct tape tends to degrade and “ribbon” as it degrades leaving behind a mess to clean up.
Glue Composition: Glue composition of the tapes listed above have high chlorides in the adhesive. The adhesives in the glue break down over time and leaving a sticky mess behind. The high chlorides in the glue cause the flange face to “blacken” making cleaning a chore. Tape such as the ones referenced above should not be used on stainless steel flanges. The use of high chloride adhesive on stainless steel flanges is a major no-no.