摘要 |
<p>A formation testing while drilling (FTWP) apparatus and method are provided for obtaining highly accurate pressure measurements in a well borehole using a combination of an absolute and a differential pressure sensor for obtaining absolute pressure measurments under high temperature gradients. A high accuracy quartz absolute pressure sensor is used during a period of constant temperature. A sensor output defines a start range for differential sensor, which has less absolute accuracy but is less susceptible to temperature effects of high temperature gradients.</p> |