These oil flowmeters are positive displacement type flow meters which are used in a wide variety of applications including measuring of boiler fuel oil and diesel oil, as well as for transactions of kerosene, light oil and heavy oil. Gear Type: This flowmeter employs a gear-type rotor for small-volume flow of low-viscosity oil in heat control applications, etc. It can be used without modification to measure kerosene, light oil, or heavy oil. Measuring accuracy is В±0.5 %. Roots Type: This flowmeter is widely used for transaction and in other applications. The roots rotor rotates without physical contact, resulting in extremely low pressure loss. In addition, its accuracy remains virtually unchanged over a long period of time.