they picked Hawkeye [because of] the dry seal design
— Facilities Engineer
Most sealed/sour level gauges use fluid or grease to achieve a vapor-tight seal. This fluid or grease has to be maintained. Operators are required to climb to the tank roof to maintain the gauge head. This can be particularly dangerous in winter conditions and sour applications. Additionally, tanks roofs are not designed to support the weight of a man.
As part of their best practices for safety and efficiency for tank builds in Alberta, one major producer was reviewing all aspects of tank fabrication. Their goal was to clearly define a standard
for all of their tanks that embodied all of the best practices they have observed. “[We] wanted to keep operators off the roof of the tanks.”
The Hawkeye Redtail and Roadside models incorporate a single axel, double pulley design constructed of a robust cast aluminum housing and stainless steel internals. This design provides a
“Dry Seal” that eliminates the use of fluid or grease to prevent harmful gasses escaping.
The dry seal design eliminates maintenance required on the gauge head to sustain the seal. As a result, operators spend less time on the tank roof. Another significant advantage of the dry seal design allows operators to attach/retrofit a float activated transmitter (Goshawk) to the gauge head without being exposed to the process. The Goshawk provides both an electronic signal and a mechanical level indication on a single set of process connections.