If during this project ***underpressure drilling***, directional boring, guided auger boring (pilot pipe jacking), tunnelling or microtunnelling are to be carried out, its description must require the contractor to comply as follows:

i.e. ***underpressure drilling*** on all pipe material

sources:

Under Pressure Pipeline Solutions Limited - ***Underpressure drilling*** is the method of taking a branch of connection off ... Underpressure drilling can be used on any pipe material including cast iron, ...
www.underpressurepipeline.co.uk/underpressuredrilling.html -

***Under pressure drilling or hot tapping, stopple and stoppling*** - Under pressure drilling or hot tapping method is usually adopted as the work needs to be carried out without having to disrupt the day to day running of the ...
www.alliedpipefreezing.co.uk/hot-tapping.htm -

Under Pressure Drilling - Flowcheck | Flow measurement and ... - ***Under pressure drilling*** enables tapping points to be installed into pressurised pipes without the need for isolation and without any disruption to the ...
www.flowcheck.co.uk/under-pressure-drilling.../index.php -

***Directional boring - Wikipedia, the free encyclopedia - Directional boring, commonly called horizontal directional drilling or HDD, is a steerable trenchless method of installing underground pipes, ... a three stage process wherein first stage drills a pilot hole*** on the designed path and the ...
en.wikipedia.org/wiki/Directional_boring -

ISTT - The International Society For Trenchless Technology ... - ***Trenchless pipe installation. Guided auger boring (Pilot pipe jacking)*** · Dry boring method · Horizontal Directional Drilling method (HDD) ...
www.istt.com/index.cfm?menuID=65...63... -

***Microtunnelling,Microtunneling, Horizontal Directional Drilling ... - Rockman · Pilot Tube Microtunneling System*** ... Horizontal Directional Drilling. The HDD 4440 Directional drill is one of the most powerful machines in ... and efficient alternative to the open trench method of laying pipes and services. ...
www.nodigequipment.com.au/ -