One competitor achieved a misclose of 3.5 m, or nearly 3%. On top of this accuracy the TwinGyro™ performed the required eight surveys in half the time achieved by the competition.
Instant QA/QC or a back-up tool What benefit is there really in running two gyros at the same time? The major benefit is that the two independent tools are carefully aligned and calibrated together, so that the results from the two tools are directly comparable. You get a direct apples-to-apples comparison of two independent surveys that are known to have been run in completely identical conditions. The tools therefore act as a quality control of each other. If there is a significant difference in results then you know that something needs to be investigated in the hole or in the tool function. By using the averaging function built into the software you also get the most accurate result possible from the two surveys, along with the two independent surveys. You are spoilt for choice in the data that can be used from a single run down the hole. Alternatively, in the rare instance that one of the gyros in a TwinGyro™ unit breaks down then it can simply be deselected in the software for use in surveying. You still have one fully functioning gyro in the system so you can continue to survey.
Multiple survey modes in one tool The TwinGyro™ implements three main survey modes: fast continuous, traditional multishot and delayed start. Fast continuous The fast continuous mode is the defining mode of operation for the TwinGyro™. By connecting a wireline depth encoder to the survey computer the TwinGyro™ can be run at speed into or out of the hole, without stopping at every station. In this way a deep hole can be surveyed in a fraction of the time of a standard multishot gyro system. The desired station interval can be changed in processing after the survey is downloaded, so virtually any station interval can be generated after surveying from a single run in the hole. Faster. Deeper. Safer.
Traditional multishot The familiar multishot gyro survey is the mainstay of most survey operations and is of course available for the TwinGyro™ as standard. Users of the isGyro™ or other similar systems will feel comfortable running the TwinGyro™ with little introduction. Delayed start The delayed start mode allows you to start a TwinGyro™ in sleep mode and have it wait for up to several days before it wakes and begins recording survey data. Using this mode the TwinGyro™ can be lowered and left down hole for as long as necessary, for example, before the surveyor returns to begin surveying. TwinGyro user
All-new software In order to utilize the full potential of the TwinGyro™ system, and its sister systems the SlimGyro™ and the rugged version of the isGyro™, entirely new software has been developed. While existing users will still feel at home using the new Surveyor software, the functionality, customizability and data presentation have all received major upgrades. The software includes all-new features that have been added to our gyro systems over the years. This includes improved calibration procedures to exploit the TwinGyro™ capabilities. The processing has been upgraded and optimized for more speed, using our specialist in-house knowledge of inertial navigation and software development. All survey result data can be viewed graphically directly in the software, and there are tools to plot all surveys and average surveys together to give instant feedback on survey results. The data output is compatible with isAnalysis™, our powerful and popular software for analysing, editing and exporting survey data from a range of tools.
No extra overhead There is no extra overhead in running a TwinGyro™ compared to a regular rugged isGyro™ or SlimGyro™. The intelligent software handles both TwinGyro™ components simultaneously so that downloading two surveys over Bluetooth is just as fast as downloading a single survey. The data processing in the isGyro™ was already fast compared to other similar tools. But the processing for the TwinGyro™ benefits from years of further development and now takes literally seconds to process an hour’s worth of data on a standard field PC. The running gear remains the standard 38-mm kit supplied by Inertial Sensing. The TwinGyro™ will fit all running gear and heat shields that fit the standard isGyro™.
Time comparison Utilizing the fast continuous survey mode of the TwinGyro™ makes time comparisons with other gyro systems almost meaningless, since by surveying using a depth encoder attached to the winch it is possible to generate stations ranging from every meter up to every 30 meters or more, without
COMPARISON OF TIMES REQUIRED TO COMPLETE A SURVEY OF THE GIVEN NUMBER OF STATIONS TWICE HOLE DEPTH (METERS)
300
600
1200
STATIONS (3 M) PER SURVEY
100
200
400
TWINGYRO™ (CONTINUOUS*)
10 MINUTES
20 MINUTES
40 MINUTES
TWINGYRO™ (MULTISHOT)
1 HOUR
2 HOURS
4 HOURS
“STANDARD” REFERENCE GYRO
2 HOURS
4 HOURS
8 HOURS
NORTH-FINDING MULTISHOT
13 HOURS
26 HOURS
52 HOURS
* Assuming an average winch speed of 30 meters/minute. Depending on winch this can be faster. 23