Wet/dry sounding reel tape. Final report

摘要

The Interim Waste Technology (IWT) section of the Savannah River Technology Center evaluated a demonstration model of a modified reel tape for High-Level Waste Engineering. The standard Robertshaw Model 185 reel tape is used in the Tank Farms as a conductivity probe to monitor liquid levels in waste tanks within + 0.1 in. The demonstration model features a device that also stops the reel tape motor on loss of tension in the tape. Tests conducted at TNX showed that the modification enabled the reel tape to locate solid surfaces such as saltcake within approximately +0.5 in. The modified reel tape also located, within approximately +0.5 in., the sludge/supernate boundary exhibited by sludge from TNX Tank F, which closely approximates the sludge expected to exist after the Tank 42H sludge wash process. IWT recommends that the tape tension modification, with the associated controls, be installed in all Robertshaw reel tapes used in the Tank Farms. The modified probe should also be considered for installation in those tanks that have a free or submerged semi-solid surface.