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Fuel Oils #5 and #6

Other Names: Bunker fuels, Bunker "C" Oil
Viscosity: Varies from 66-13,000 cPs. @ 21°C / 70°F. Normally handled at temperatures in the 120 to 150F range (50-1700 CPs.) for ease of handling.
Sp. Gr.: 0.90

Remarks: Fuel oil #5 and #6 are semi-solid or very viscous at room temperatures and must be preheated before being used. They are used as a fuel in many large commercial and public buildings as well as in large industrial plants and power plants. Occasional abrasives and/or sludge in these heavy oils can cause some pump or seal problems. Avoid the use of long suction lines with heavy fuel oils to prevent cavitation-type problems.

Pump Notes: Cast iron construction is satisfactory. Viton® elastomers are usually acceptable with PTFE sometimes required depending on the particular liquid. Mechanical shaft seals are recommended.

See also:  Fuels, #1 through #4 Fuel Oil

Viton® is a registered trademark of DuPont Dow Elastomers®, L.L.C.