Transformer oil - comprising blend of petroleum raffinate and opt. aromatic fractions with pour point depressant (HU 28.1.77)

摘要

Transformer oils comprise a blend of (a) 0-80 wt% of a raffinate derived from a petroleum fraction A, (b) 30-95 wt% of a raffinate derived from a petroleum fraction B, (c) 0-15 wt% of an aromatics-rich petroleum fraction C, (d) =1.5 wt% of a pour-point depressant, and opt. (e) 1.0 wt% of an antioxidant. Characteristics of the fractions, each given in order for A, B and C are trivial b. pt. (degree C): =280, =280, =280, final b. pt. (degree C): =450, =450, =460, flash pt. (degree C): =135, =135, =135, Specific gravity (20 degrees C): 0.870-0.889, 0.840-0.860, 0.960-0.990, pour point (degree C): -40, -15, +5, aromatics content (wt %), 16.5-30, 8.0-12.5, =40.0, M/B ratio: 1.8-2.8, 2.5-5.0 0.8-1.8, PNA content (wt %) 0.8-2.0, 0-0.8, =35, (where the M/B ratio is the ratio of mononuclear to binuclear aromatics, and the PNA content is the content of polynuclear aromatics contg. 2 rings). The oils satisfy all requirements w.r.t. pour point, viscosity-temp. curve, dielectric loss factor (tan Omega), oxidative stability and gas stability.