Formulating advanced 4 centistoke gas turbine oils - a feasibility study

A formulation study has been carried out to assess the feasibility of developing advanced gas turbine lubricants in the (4 cSt) viscosity range intermediate between current MIL-L-7808 and MIL-L-23699 lubricants. Using additive technology developed on advanced MIL-L-2 7502 oils the authors have formulated several 4 cSt polyol ester base stocks. Eight of the blends thus far tested have shown good to acceptable performance in the Erdco Bearing Rig Test run under MIL-L-27502 conditions. Various other key targets of a proposed new specification have been met or closely approached.