Base Oil 500N-HVI

About This Product

The largest single outlet for Base Oil 500N-HVI is heavy-duty diesel engine oil for trucks, buses and off-road machinery. Older fleets running monogrades can be served by blends based largely on this grade, and multigrades use it with the 150N-HVI to satisfy cold and hot viscosity requirements at once. Reciprocating air compressor oils are another outlet, and here carbon residue is the property to watch: oil that reaches hot discharge valves can leave carbon that fouls the valves and, in the worst case, leads to fires in the discharge line. Grease manufacturers use the grade as the base oil in soap-thickened products, where base oil viscosity governs the thickness of the film reaching the bearing.

Specified at 10.5 – 11.5 cSt at 100 °C, the engine oil grading temperature, the grade tells a diesel oil formulator directly how much hot viscosity the base oil will provide before any polymer is needed. Its viscosity index of min 95 limits how thick the oil becomes in a cold engine. The minimum open cup flash point of 227 °C points to very little light material, which matters because light ends evaporate in the hot piston-ring area, increasing consumption and leaving the remaining oil thicker. Carbon residue may reach 0.18 wt %, more than on any other HVI neutral; ASTM colour is max 3.5, pour point max -6 °C and total acid number max 0.05 mg KOH/g.

This is the top of the HVI series by weight and the main source of viscosity in a high viscosity index blend. Refiners take it from the heaviest part of the vacuum distillate, adjacent to the residue that becomes bright stock, and process it with the same extraction, dewaxing and finishing steps used for the lighter grades.

Its closest comparison is the 650N-MVI, which covers almost the same viscosity at 100 °C. What separates them is viscosity index: for an engine, which has to cope with cold starts as well as full load, the 500N-HVI is the right specification. Relative to the 400N-HVI it is a little heavier and somewhat darker, and where it cannot provide enough body alone, a portion of Bright Stock BS-MVI makes up the difference.

BG Petro Chemicals supplies the grade from Pakistan, allocating monthly volumes from a lube base oil output of 16,500 MT shared by every grade. Engine oil blenders usually receive bulk or ISO tank deliveries, while drums, IBC tanks, flexi bags or custom packaging are available for other customers. A certificate of analysis covers each lot, and the TDS and SDS are available on request.