Water penetration test
In most cases the so-called water penetration test is well-suited for the determination of the condition of the blasting process and the blasting media in respect of possible contamination by oils and greases. For this test an initial blasting media sample is taken from the air flow separator at the blasting system. With the water penetration test, tap water is simply allowed to drip onto a pile of blasting media. Water immediately penetrates a pile of oil and grease-free blasting shot. Newly casted shot is always free of oil and grease.
- The water drains quickly in the cleaned blasting media, on the greasy blasting media it remains standing
Due to the low surface tensions of oily blasting media, the water remains as droplets on top of the pile. As a rule, the longer it remains, the greater is the contamination due to oil or grease.
In the running operation, the water penetration test should be carried out regularly for process control, for example in the preparation of anti-corrosion coatings.
Attention! With cut wire shot, lubricant may already adhere to that as a result of its production process!