The Shand & Jurs Model 93376 Semi-Automatic Tank Gauge and Sampling Lock has been designed as an intermediate step between hand gauging and fully automatic tank gauging. The inherent inaccuracy of hand gauges has led to the design of this tank gauge, which entirely eliminates the human element in the sequence of lowering the tape and bob to the bottom of the tank in order to obtain an “innage” reading.
In this gauge, a hollow bob is used in place of the conventional plump bob. A spring mechanism is adjusted against the weight of the hollow bob so that when the bob touches the tank bottom or datum plate, payout of the tape is automatically stopped and the tape is kept under constant tension, preventing tipping of the bob or overshooting the gauge. By substituting a sampling bob for the hollow bob and locking the spring mechanism, the device becomes a sampling lock.
The Model 93376 is available in cast steel (for working pressures up to 125 Ibs.) Other materials are available upon request. A rubber plug closure valve, which can be closed on the gauge tape, is used between the gauge and the tank to isolate the gauge head from the tank vapor space during gauging operations. A gate valve under the rubber plug closure valve is recommended for all working pressures above 10 Ibs., to permit inspection of the unit.