Hawk - Data Quality, Power , Portability & Safety
It is an engineering challenge to develop a product that has safety forefront with a low power and still keep the data quality. All of this pointless if it is not easy for a operator to setup for a test. With the Hawk CalScan has succeeded in producing a high quality easy to use instrument.
Accurate reservoir engineering requires precise data, unfortunately most off the shelf 4-20mA pressure sensors are not adequate for the task . As the temperature changes in these sensor you will see a change of pressure that trends with temperature. These temperature induced pressure ( TIP ) waves can make analysis difficult. The Hawk extreme pressure stability, without sacrificing transient response time, comes from our advanced 24 bit analog circuitry, proprietary digital filtering and multi-step calibration that can span from -40°C to 80°C. All three technology's work together to give the user the accuracy and repeatability needed.
Its unacceptable to have to use car batteries just to log a couple of pressure sensors every 30 seconds. The Hawk in contrast to be as compact and energy efficient as possible. By using low power electronic designs we can run the Hawk 9000 for over 2 years using two 3.6 V Lithium C-Cell at a 30 second sampling rate. The choice to use lithium cells instead of rechargeable NiCads or Lead Acid batteries was simple. Since the life of the battery is so long rechargeable batteries are not needed. There is also a huge draw back with rechargeable's in cold temperatures. The performance of these rechargeable batteries are extremely poor typically loosing 2/3 of their capacity. With over 5 years of field use in Northern Canada the Hawk 9000 has shown they can run down to below -40°C for extended periods without problems.
Most standard industrial equipment use explosion proof enclosures to allow their electronics to be used in hazardous locations. When a spark or a heat source causes combustion within the enclosure, it is designed to be capable of containing the internal explosion of the flammable vapor air mixture and allow the escaping gases to be cooled below the ignition temperature of the surrounding atmosphere. This prevents an explosion outside the case.
An explosion proof case will cool the hot gases as they vent to the atmosphere, thereby preventing a explosion. Unfortunately making a data logger that is explosion proof greatly reduces portability
Cooling is insured by making any joints or threads sufficiently long so that any flames are snuffed out and hot gases are cooled before reaching the outside atmosphere. This method of protection is fine for permanent installations but makes makes rigging in and out extremely difficult as all connections need to be in explosion proof steel conduit and sealed for portable tests systems.
Instead our Surface box uses another method of hazardous location protection called intrinsic safety.
There are two major benefits of this technology. It allows you to all weather flexible cable instead of explosion proof conduit to interconnect external sensors.
Since the Hawk is completely Intrinsically Safe only simple cable, not explosion proof conduit, is needed for a interconnect to sensors, greatly simplifying the install where hazardous gases are present
Secondly you can actually open the lid of the Hawk without having to do a sniff check to verify that there is not a explosive atmosphere present. The safety of an explosion proof design is compromised when the case is open, so checking for flammable gases before opening the lid is a must. With the Hawk you don't have to worry about your operators safety if they fail to do a sniff check, since it's not required.
The Hawk 9000 is fully CSA and UL approved to be Intrinsically safe for Div I Class 1 Groups A,B,C,D. This is a link to CSA's web site where you can see our certification.
Even worse though is when surface pressure recorders are used on a wellhead and not approved for hazardous location. Typically they use an explosion proof case where the gauge as a whole has not been tested for safety. These gauges can be dangerous and are illegal to use in a hazardous location.