What are the current types of densitometers used in oil and gas projects?

The liquid density meters produced by the British company Moebley feature high performance; for example, the advanced model 7835. Its working principle involves a straight, smooth tube with an inner diameter of 1” that resonates under the action of an electronic feedback system. The vibration frequency changes as the density of the liquid inside the tube varies. Its unique structure and mode of vibration overcome the shortcomings associated with conventional single-tube vibrations, thereby enabling very high performance and excellent stability. Improvements to the resonance mechanism allow for further enhancement of the meter’s performance. The relationship between frequency and density is given by: ρ = K0 + K1T + K2T2, where ρ represents the liquid density, T is the oscillation period of the vibrating tube output by the sensor, and K0, K1, K2 are constants of the sensor, which are calibrated at the time of manufacture. Scope of use: The 7835 liquid density meter, designed for use in commercial measurement applications, has long been employed for measuring the density of crude oil, refined oils, and non-corrosive liquids. Under pipeline operating conditions, it offers high precision and excellent repeatability. Its vibrating elements are made of Ni-Span-C material, providing good long-term stability and temperature performance. All other materials in contact with the medium are 316L stainless steel. The instrument can handle pressures up to 15 MPa, and there are various flange attachments available for use.