Practical application analysis of differential pressure transmitter in a certain oil depot

Differential pressure transmitterPractical application (case study)

In a certain oil depot project in Jiangsu, the editor applied this idea to practical design.

Design conditions: 2000m3 oil tank, diameter d=14.5m, height h=14m.

Primary gauge: Choose a flange type explosion-proof differential pressure transmitter to prevent blockage of the pressure pipe due to sedimentation of dirt at the bottom of the tank. The transmitter has a range of 0-140kPa.

Secondary meter: WP series intelligent light column display alarm is selected, with universal signal input and the range can be changed arbitrarily. The liquid level is displayed using a light column, and the tonnage of oil is displayed using numbers.

Design a liquid level alarm device at the top of the oil tank to prevent oil overflow and serve as a dual safety measure. In application, since the measured value is directly in tons, regardless of the type of oil stored in the oil tank, the value displayed on the secondary table is the ton of oil in the tank, avoiding the trouble of measuring density for conversion.

In general, oil products are often transported by pumps and measured by elliptical gear flow meters. Due to the limited accuracy of flow meters, which can reach up to 0.2 levels, density calculations are also required, resulting in some discrepancies in the results and causing measurement disputes. Nowadays, because the measurement results of oil tanks are in tons and the accuracy can reach 0.2 or even 0.1 levels, the measurement results are more accurate compared to volumetric flow meters. Although the absolute error of measurement results is relatively large due to resolution issues when small quantities of oil products are in and out of the warehouse, the high accuracy and small relative error when large quantities of oil products are in and out of the warehouse cannot be compared to other measurement methods, making it particularly suitable for monthly, quarterly, and annual inventory.

Practical application has proven that its main advantages are: ① simple and convenient installation and maintenance; ② The reading is intuitive, direct and clear, and can directly read the inventory level of oil products; ③ Exemption from density measurement and conversion.