Process for cleaning oil-wetted parts

US5762717A · kind A · utility

Assignee

• ALD VACUUM TECHNOLOGIES GMBH · DE

Inventors

• Franz Hugo · Aschaffenburg, DE
• Erwin Wanetzky · Großkrotzenburg, DE
• Albrecht Melber · Darmstadt, DE
• Manfred Raschke · Niederrodenbach, DE

Key dates

• Filing date: Jun 17, 1996
• Grant date: Jun 9, 1998
• Expiry date: Jun 17, 2016

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C23G5/00
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

In a process for cleaning oil-wetted structural parts, a vacuum furnace (1) is first evacuated to a defined first pressure to eliminate residual air. Then an inert gas is introduced until a second, subatmospheric pressure is reached, which is above the first pressure, and the inert gas is circulated inside the vacuum furnace. To reduce the heat-up times and to conserve energy and inert gas: PA1 (a) the second pressure is above the vapor pressure curve of the wetting oil and is reached by flooding the vacuum furnace (1); PA1 (b) the inert gas feed and the evacuation are interrupted after the flooding, and the inert gas and the oil vapors are circulated exclusively in the interior of the vacuum furnace (1); and PA1 (c) upon completion of the heat-up period, a connection is established from the vacuum furnace (1) to a condenser (11) and to a vacuum pump (12); the pressure is lowered to a value below the vapor pressure curve; and the oils thus evaporated are withdrawn and condensed.