English to Italian Tech/Engineering Metallurgy / Casting

Dealing with Liquid Penetrant examination of welds. The sentence: Mechanical imperfections at the surface are revealed by bleeding out of the penetrant. The surface shall be closely observed to monitor the behaviour of indications wich tend to bleed-out profusely. If bleed-out does not altre the examination results, longer periods are permitted.
Deve essere qualcosa tipo colatura, fuoriuscita............o no? Tks