Electronic manometer under the oil well

An electronic manometer is presented to study the formation fracturing process by high pressure gas in an oil-well and develop a kind of torpedo used for this process. It can record the pressure-time relation over the whole process. The measurement error is less than 1.5% under a temperature up to 150/spl deg/C and a pressure of 200 MPa. In this paper, a new type of self-compensating charge amplifier, an ASIC and a calibration system are discussed in detail. Other units of the manometer are described briefly. The field test results are also presented. >