Current situation of downhole pressure gauge in China

With the deepening of oil and gas exploration and development, the quality of oil test data is required to be higher and higher. At present, in conventional well testing, the method of shut in with bottom hole test valve is widely used in China. The storage electronic pressure gauge is used to test the bottom flow pressure and the bottom shut in pressure, and then the pressure gauge is dragged into the test depth along with the test valve. After that, the pressure gauge is pulled out and the data can be played back by the computer to obtain the downhole pressure and temperature data.

This method to measure pressure and temp  has two disadvantages . First, it can not monitor the changes of bottom hole pressure and temperature in real time. Second, before the pressure gauge is lifted out of the bottom hole, the bottom hole state and the actual bottom hole condition cannot be completely, accurately and timely determined on site. Therefore, in conventional well testing, it is difficult to properly determine the shut in time, and the construction status is estimated intelligently by experience, so it is impossible to make accurate judgment, which brings many problems to the implementation of field testing.

Why wireless downhole pressure gauge has become a hot research?

1. wireless downhole pressure gauge system is more secure. No cables are required, which significantly reduces the health and safety injury caused by the high pressure and potentially harmful fluids.

2. The operation is smoother. Through wireless acoustic telemetry technology, instead of triggering downhole tools by annulus pressure, the limit of casing pressure is reduced, and the influence of kill mud of high-pressure well on annulus pressure control tools is avoided.

3. Improve the measurement and control quality. Based on reservoir response and downhole data, the test program can be changed in time. Increase the quality of data acquisition during DST testing.

4. There are successful cases in the world, which increase the confidence of the research. Halliburton, Schlumberger and other companies have been widely used in oil fields.

High pressure well wireless transmission test string diagram

S314 high temperature resistance pressure transmitters (for downhole pressure gauge)