Detection of acid in freezing mixts. of refrigeration plant - using ionised plastics contg. an acid indicator installed for visual inspection

摘要

Acid is detected in the freezing mixt. of refrigeration plant by introducing press-moulded material e.g. in form of tablets, made from ionised plastics granules with a binder and contg. an acid indicator, into the pipeline contg. the circulating freezing liq. in such a way that it may be visually inspected through an inspection glass. There is no need to draw samples from the system, hence no risk of leaks. The test material may be made of ionised polystyrene granules. The acid indication may be phenolsulphophthalein (phenol red pH 6.8-8.2 yellow-violet). The binder may be a mixt. of an initially liq. synth. resin and a liq. additive which evaporates during polumn. of the resin.