Background

When the oil is discharged from a single well in an oil field, the extracted crude oil contains water, and the water content is not fixed which results in inaccurate measurement for the crude oil density in the process of measuring crude oil nuclear production.

In order to solve it, the automatic intelligent analytical analysis and treatment is applied for the dissolved gas contained in crude oil in the metering pipeline. The density of the mixed gas mixture can be accurately determined without separation, without degassing, thereby realizing accurate measurement of crude oil production.

Difficulties

(1) The measuring medium is an oil-water mixture with high temperature, high viscosity and it has certain corrosiveness.

(2) 0.5% FS accuracy, good stability

Solution

MDM3051K-LP series differential pressure transmitter, with a double flange capillary tube, can reduce the interference caused by high viscosity, high temperature, and corrosive of the medium. It is suitable for differential pressure measurement in a closed environment.

Details:

(1) P = ρgh, the principle to calculate the crude oil density value.

(2) Measuring the differential pressure value on a vertical fixed length pipe to reduce the influence of high viscosity and high temperature of the medium.

(3) The measurement range needs to match the fixed pipe length.

(4) 0.5% FS accuracy.

After testing the pipeline valves and various components, the measurement data is accurate, and the effect is achieved onsite.

Product

Troubleshooting and performance analysis of intelligent digital pressure gauge | digital display pressure gauge?

Troubleshooting and performance analysis of digital pressure gauge?

Troubleshooting and performance analysis of digital pressure gauge?

1、 Precautions for site use

1. The field service conditions of digital pressure gauge shall meet the requirements of technical parameters of this instrument. The instrument range shall be selected correctly. The measured pressure shall not exceed the upper and lower limits of the instrument, and sufficient overpressure safety margin shall be reserved.

2. The measured medium temperature of the digital pressure gauge shall not exceed the working temperature range of the instrument, and the sealing and vibration resistance of the instrument shall be ensured when it is used in corrosive and vibration places.

3. The digital pressure gauge is a vertical downward direct installation type, which can be directly installed on the pressure interface of the measured pipeline. During installation, avoid the formation of "closed pressure" between the instrument connecting thread and the valve in front of the gauge (observe the indicated value and pay attention to the pressure response time). If this pressure is formed, it should be eliminated in time, otherwise the measuring element will be damaged and the medium will leak.

2、 Operating instructions

The sensor and display processing part of the digital pressure gauge adopts an integrated design structure, which is easy to use. The digital pressure gauge and the tested mechanism are directly connected by threads, and there is no requirement on the placement angle of the digital pressure gauge. Before using the measurement, the approximate pressure range of the measured target should be estimated to avoid mechanical damage to the sensor due to excessive pressure exceeding the measurement range. The pressure response time of the digital pressure gauge is 2S.

3、 Troubleshooting

Digital pressure gauge belongs to mechanical and electrical products. During transportation and use, due to environmental interference and improper human operation, the instrument may not work and display normally. For simple faults, users can eliminate them by themselves. Other faults need to be returned to the manufacturer for repair. The following list shows the troubleshooting methods.

Troubleshooting of digital pressure gauge

1. There is no font on the screen. Replace the battery

2. When the pressure increases, the font does not change. Take out the battery, wait for 30 seconds, and then reinstall it

3. The font is damaged by non digital LCD, which shall be returned to the factory for repair.

4. The value is obviously inaccurate and the sensor is damaged. It should be returned to the factory for repair.

5. The accuracy is changed and returned to the factory for re calibration

Performance analysis of intelligent digital pressure gauge!

1. Economic benefit analysis

After long-term operation, the intelligent digital pressure gauge shows that the fault rate is low, the maintenance cost is low, and the operation cost is reduced. The maintenance workload is very small, mainly for regular inspection and verification. Even if there is a problem, it can be easily found through manual operation to reduce unnecessary waste discharge. The price of intelligent digital pressure gauge is higher than that of ordinary pressure gauge. Although the cost is increased, its service life and accuracy grade are much higher than that of traditional pressure gauge.

2. Analysis of progressiveness of Technology

The intelligent digital pressure gauge has few movable parts, small maintenance workload, high accuracy and reliable operation. It is convenient to set, correct and debug through manual operation, with strong operability and compatibility, convenient debugging, multi parameter measurement and wide measurement range.

3. Precautions:

The intelligent digital pressure gauge must be consistent with the on-site installation position during indoor calibration, otherwise, it will cause large zero error.

4. Concluding remarks

The long-term use of customers shows that the intelligent digital pressure gauge has a wide range of applications in industry, petrochemical industry and other fields, and is also the inevitable trend of field instrument development in the future. It is of great significance to reduce costs and improve economic benefits.

Digital pressure gauges measure the pressure within a system in a special manner. They convert the pressure to an electronic signal. The gauge shows the pressure using a digital display, furthermore the signal can be used to control equipment. Digital gauges in comparison with analog ones have a higher accuracy. Read our article on analog pressure gauges if you want to learn more about that type.

Working principle

Digital pressure gauges make use of pressure sensors in order to convert pressure to an electronic signal. Different types of pressure sensors exist, but the most commonly used is a piezoresistive pressure sensor. This sensor consists out of a diaphragm that is equipped with piezoresistive elements. The medium pressure causes the diaphragm to deflect, this deflection causes a change in cross-sectional area of the piezoresistive elements that is directly coupled to the electrical resistance. For a more in depth explanation please read our article on electronic pressure measurement principles.

Why choose a digital over an analogue pressure gauge?

Next to a higher level of measurement accuracy digital pressure gauges offer options that are not available for analogue ones. A few examples of possible options are:

• Backlighting: If pressure readouts are needed in dark conditions this options proves to be a great solution. Backlighting ensures that you are able to read the display in every lighting condition.
• Min/Max values: This option provides better analysis of the set pressure in a system.
• Bargraph display: The bargraph display shows the trend of the measured pressure. You can for example easily see if the pressure has an increasing, decreasing or steady trend.
• Battery powered: This ensures that the pressure can be read in case of power outage.
• Rotatability: Most digital pressure gauges allow for the display unit to be rotated to a large degree (e.g. 300°)

Read our selection tips for pressure gauges to learn more about this subject. For more information on various pressure gauges read our articles on bellows pressure gauges, diaphragm pressure gauges, or bourdon tube pressure gauges. 

Digital pressure gauge accuracy

The accuracy of digital pressure gauges is expressed as a percentage of the measurement span. The accuracy of these gauges is combined from it’s non-linearity, hysteresis, End value deviation, zero offset and span error. For a detailed explanation please read our article on understanding pressure measurement accuracy.