Borehole Pressure Cells

Description

The standard Borehole Pressure Cell (BPC) is used to measure rock stress changes and is designed to be grouted inside a borehole. The BPC is manufactured from two steel plates welded together around their periphery. The plates are deformed into a “dog bone” configuration so that they can be expanded easily, without damage to the welds. Hydraulic oil fills the space between the two plates and a high-pressure stainless steel tube connects the plates to a stainless steel pressure gauge and/or a pressure transducer.

Specification

Standard Ranges
  • 20, 35, 75 MPa
Resolution
  • 0.25% of range (approximately)
Accuracy
  • 0.25% F.S. (gauge); 0.1% F.S. (VW transducer)
Borehole Size
  • 57 mm
Temperature Range
  • −20°C to +80°C
L × W × H
  • 203 × 47.6 × 12.7 mm (borehole flatjack only)
  • 508 × 47.6 × 12.7 mm (borehole flatjack with stainless steel tube)