Trenchless Technology vocational qualification project

HDD machines provide state-of-the-art solutions for developing subsurface piped networks in inaccessible/ sensitive locations where open cut pipe laying is not feasible or advisable.

However, the inaccessibility associated with some HDD jobs can lead to mistakes which are both costly and disruptive to public utilities. Furthermore, the sophisticated machinery involved with HDD jobs can also be subjected to stresses beyond their design capacities if handled improperly, resulting in damage to machinery in varying degrees.

There is therefore a need to regulate the operation of drilling machines and only allow qualified staff to operate the machinery, and to this end, IndSTT has proposed a set of competency standards for the qualification of HDD operators.

To operate HDD equipment, operators need to display the minimum qualifications to handle cable and pipe installations successfully and reliably. IndSTT is overseeing this program in India and other southern Asian nations.

Any operator of HDD machinery must undertake the prescribed competency tests at defined intervals to be certification as a qualified driller. At no point of time should any machine owner/operator permit non-certified persons to operate drilling machines.

Prior achievement
For recognition of prior achievement, persons need to have five years work experience as an assistant machine operator, or should have a diploma in civil/electrical/mechanical automobile engineering from a recognised institution.

Performance standards
To qualify for testing, operators must display competence in the following:

• Consideration of the most important aspects of site preparation when planning a project;
• Awareness of general safety precautions and ability to use them;
• Awareness of electrical safety precautions and ability to use them;
• Ability to decide a clear bore path, depending on the location and depth of existing utilities;
• Ability to understand maps, plans and reports on existing networks, such as GPR report;
• Capacity to assemble and set up the drill unit correctly under varying job site conditions;Capacity to assemble and set up the drill unit correctly under varying job site conditions;
• Ability to select the suitable bore method and drilling fluid to correspond with the soil conditions;
• Ability to plan the bore, set up the bore and drill the pilot hole;
• Ability to apply the drilling head location technique and its functions successfully;
• Ability to assemble and dissemble the down-hole tools, and maintain them;
• Ability to select the backreaming technique to correspond with the soil conditions and the pipe;
• Ability to anticipate problems in machine; and,
• Ability to carry out common maintenance and problem solving measurements independently.

Minimum performance standards
While executing drilling operations, operators need to display the following minimum qualifications:
Safety during work
This includes observance of general precautions necessary for safety of structure, and the machine itself, as well as the use of necessary aids for safety.

Read working drawings
Workers must be able to understand the scope of work to be undertaken as outlined in a set of drawings and/or a sketch of the machine and related tooling, and execute this work.

Knowledge and use of equipment
Operators must be able to properly identify equipment and tools, properly park/store of equipment and tools, properly use consumables and properly use tools.

Knowledge of machine operating procedure and sequence
Operators must be able to check that the machine is properly connected to the desired power points and that all related accessories are connected properly, and must be able to ensure that voltage, frequency, current potential, and polarity are checked.

Knowledge about defects, their remedy and acceptance limit
Workers must be able to identify any defects in a machine, know how to remedy any such defects, and know the acceptance limit of any machinery as per the standard code.

Supplementary knowledge
In addition to the evidence of prior achievement, trainees need to show evidence of the following supplementary knowledge before being permitted to operate HDD machinery independently: Reading and writing in vernacular language; the ability to conduct area and volume calculations; an understanding of drilling fluid mix; an understanding of different types of cuttings from the drill holes and actions needed to avoid related accidents; knowledge of various basic construction norms; knowledge of basic electrical hazard prevention methods; and awareness of the basic operator’s manual for HDD machines being used.

Syllabus for HDD testing
In order to verify the above competencies, the test is aimed to evaluate the workers’ knowledge in the basics of mathematics and natural sciences; horizontal drilling units; project basics; project realization; drilling fluids; borehole hydraulics; drilling fluid circulation; disposal; drilling string; drilling tools; back reamers; location systems; pipe materials and coating; and authority regulations, safety at work, environmental protection and work sheets.