| 摘要 |
<p>A cell for acoustically monitoring the condition of a material which passes from a liq. or paste-like state to the solid state, comprises a cell body defining a measuring chamber, two electro-acoustic transducers, having planar, mutually opposed emitting and receiving surfaces, mounted in the measuring chamber, and two end portions constituting two opposed passages adapted to receive a removable sealing plug. As cement sets and progressively hardens, both the transit time and the attenuation of acoustic pulses transmitted through the cement decrease. The pressure on the cement may be controlled by a membrane and its temp. may be measured by a thermocouple.</p> |
