1.Meter heavy oil with high accuracy wide range 2.Uniform rotator,small vibration ... 1.Introduction: (1) Defination : LLT series dual spiral rotor engine oil , heavy oil , flowmeter is a highly accurate metrological instrument to measure the ... .6, 2.5, 4.0, 6.3Medium: crude oil, engine oil, high watery crude oil ,heavy oil , petroleum and chemical products with low, midst, high ...