Extremely clean required
For certain applications, including in the petrochemical industry, extremely clean surfaces are required. Consider, for example, systems that work with high percentages of pure oxygen. This application requires that the presence of organic contamination such as oils and grease is kept to an absolute minimum. Particularly at elevated pressure, even the smallest traces can lead to spontaneous ignition. That is why this cleaning process is called UltraClean or oxygen-clean cleaning.
After cleaning, we can determine the residue of organic material by means of a solvent extraction test. We perform this test and reporting according to the ASTM G93-03 standard.
The evaporation residue will be assessed according to the table below (ASTM G93-03).
- Level A < 1 mg/ft² (11 mg/m²)
- Level B < 3 mg/ft² (33 mg/m²)
- Level C < 6 mg/ft² (66 mg/m²)
- Level D < 20 mg/ft² (220 mg/m²)
- Level E < 50 mg/ft² (550 mg/m²)
- Level F Specified by the user or supplier of the parts.
Vecom has many years of experience in cleaning various metals for oxygen applications such as stainless steel, carbon steel, aluminium and chromium or copper alloys.
Depending on the types of metal used and the contamination to be removed, cleaning is carried out in one or more steps with alkaline, neutral or acidic chemical agents. Here, the metal surface treatment often includes not only degreasing, but also other treatments such as pickling, passivating and phosphating.
In addition to the cleaning procedure, the final inspection of treated material is also essential. The final inspection takes place by means of UV light, a wipe test or an evaporation test with chemically pure solvents to ensure removal of organic contamination.