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HaloVac Inert Vacuum Pump Oils
HaloVac oils have been specially developed by Halocarbon Products to meet the needs of industry for inert, nonflam-mable, hydrogen-free, reliable vacuum pump oils. Today, HaloVac oils are widely used in plasma etching (PE) and low pressure chemical vapor deposition techniques (LPCVD) with gases that react rapidly and, sometimes, explosively with hydrocarbon pump oils.
HaloVac oils are carefully fractionated inert oils tailored to specifications which combine low vapor pressures with viscosity characteristics suitable for mechanical pump systems. Halovac oils are available in three grades, Halovac 100, 125 and 190, to accommodate a range of vacuum pumps. Chemically, they are saturated low molecular weight polymers of chlorotrifluoroethylene (CTFE) with the general formula -(CF2CFC1)n-. These polymers have been the lubricants of choice among industrial oxygen users for over 40 years.
Safer than Hydrocarbon Based Oils
The compounds commonly used or generated in PE or LPCVD systems present several hazards when pumped through hydrocarbon-based oils. Oxygen and nitrous oxide can either oxidize conventional oils slowly or, more dangerously, form potentially explosive mixtures with them. Fluorine, chlorine, hydrofluoric acid, silicon tetrachloride, arsenic trifluoride, boron trifluoride, boron trichloride and aluminum chloride react with hydrocarbon-based oils rapidly to make sludges. Silanes, while they do not react with hydrocarbons, are pyrophoric and, should air or oxygen enter the vacuum system, they will ignite and cause a serious hydrocarbon oil fire.
HaloVac oils are inert to all of these aggressive compounds and since they are nonflammable they provide no fuel for a fire caused by a pyrophoric gas. The prevention of even one explosion or fire can easily justify the apparent high cost of Halovac oil. Since Halovac oils do not contribute to sludge formation, the frequency of changing oil filters is reduced significantly, greatly reducing the exposure of personnel to toxic hazardous gases.
Cold traps, often used to prevent corrosive process gases and particulates from reaching the vacuum pump, can be eliminated. The alternate condensation and evaporation of process streams in cold traps can pose serious problems if refrigeration fails and the trap heats up unexpectedly. This is especially true when the trap contains large amounts of noxious materials. Traps may also collect explosive mixtures subject to detonation. HaloVac oils' resistance to attack removes the need for traps allowing the by-products to come directly to the pump to be continuously filtered and neutralized downstream from the process.
The Halocarbon family of oils, which includes the HaloVac oils, has been used in pumps, compressors, and seals since their introduction with no reports of toxicity by any users of these oils.
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