Editor’s Note: This is a Classic Electronic Drillmasters Report that first ran in 1998. Updates to the information have been made.
A locating system is an integral part of the HDD process and it represents a substantial investment, ranging from about $10,000 to $20,000. Just as important is the fact that the locating equipment represents “the eyes” of the HDD system. It is responsible for allowing the drill crew to successfully navigate the borepath, often maneuvering around obstacles, as well as trying to overcome as much as possible of the interference caused by surrounding utilities. This is a tall order and as such, there are a number of factors that should be considered prior to selecting a locating system.
Ease of Use
Well-trained personnel are essential when it comes to efficient operations. At the same time, turnover of people can adversely affect productivity. It is therefore important that the locating system be intuitive and easy to train on and use. A locating system that is easy to train on and is also easy to operate means a shortened learning curve and ultimately more competent locators. There is a wide variety in how the various system manufacturers approach their designs but generally the more intuitive and the more information available to the locator, the better the work will proceed.
Drilling Machine Size
Although locating systems are interchangeable between the various drilling machine manufacturers, the size of the machine can, to some extent, affect the required capabilities of the locating system. A small machine with limited pullback and thrust can only undertake smaller and shorter bores. As a result, a system capable of a great depth may not be needed, but since smaller machines often work in crowded utility corridors, an accurate system and one that handles interference well may be what is required.
Locating System Requirements
Based on the information above, some of the questions that should be asked during the decision process are as follows:
- How well does the locating system handle interference?
- Does the locating system operate on multiple locating frequencies?
- What are the operating frequency(ies) of the system?
- How accurate is the system?
- How easy is it to operate or train on?
- Does the system have a self diagnostic function?
- Does the locating system offer a small transmitter for smaller drill heads?
- What are the depth capabilities of the system?
- Is the system capable of generating an electronic as-built?
- What kind of reputation does the system have in the industry?
Once a contractor has chosen a locating system, it can become quite expensive later on to change to a different design. Not only does it involve the cost of the system or multiple systems, but the cost of lost productivity and re-training can be substantial. As a company grows, the scope of work may become more varied; for example, larger river and freeway crossings. Different size drilling machines may be acquired. Such changes can lead to increased technical capabilities required of the locating system.
It is important to attempt to look into the future a little bit and select a system that either has a wide variety of capabilities inherent in the design or can be upgraded or expanded. In this way, as the projects become more complex, crews continue to use a system they are comfortable with. This allows the company to tackle more complex future projects with confidence.
The availability of technical support can be critical, particularly for the operators who are new to the equipment. Support may also be needed in the form of loaner equipment. Another consideration may be the location of the repair facility; if the equipment cannot be repaired in the United States, it may take a considerable amount of time for repairs. How widely the system is used and the size and accessibility of the dealership network are also important considerations. How good is the documentation and manuals associated with the equipment is yet another issue to bear in mind.
The locating system is an integral part of the drilling operation and consists of sensitive electronic equipment and should be treated as such. There are a number of locating equipment manufacturers, each with differing design and operational approaches. A carefully considered choice, along with recommendations from contractors within the industry, should result in successful and profitable HDD operations.
Siggi Finnsson is product manager at Digital Control Inc. and is a member of the Electronic Drillmaster Advisory Board. All Drillmaster Reports are reviewed by the Electronic Drillmaster Advisory Board: Finnsson; John Bieberdorf, The Charles Machine Works Inc.; John Archambeault, McLaughlin Mfg.; and Ed Savage, Vermeer Corp.