Proceedings of DFI of India 2015 Conference, Bengaluru, India, (DFI)
Methodology for Drilling Offshore or Onshore in Hard Rock for Deep Foundations with Pile Top Drill Rigs (PBA)
Dinesh Hinduja, Miguel Pérez
Large structures are generally exposed to dynamic and structural loading. They require usually either foundation connected to hard rock through sockets or driven foundations, which encounter boulders as well. In this regards drilling hard-rock sockets or boulder offshore or onshore can be a challenging job especially when deep foundations are mandatory. To overcome the challenge, specialized equipment like a Pile Top Drilling rig (PBAs) can be used, which have to be correctly set-up and operated in order to get its maximum drilling performance. High performance drilling with PBAs requires maximizing key elements of its operation. The configuration and management of the drill string components are important. The key elements are constant weight on bit which is done by adjusting ballast and managing thrust force; and selection of cutters and proper flowing discharge. The methodology is based on the experience from over 40 years of building and operating PBAs for different project applications. These applications include drilling offshore and onshore for: Superstructures and buildings; Drilling platforms, barges and jack-ups; Harbours, jetties, dry docks and dolphins; Bridges, piers and causeways; Marine sewerage diffusers; Offshore wind farms; Dam rehabilitation. MHWirth documented methodologies demonstrate that by using PBAs properly it is possible to improves performance of underwater drilling for hard-rock sockets and boulders which ultimately reduces project-cost.
|article #2192; publication #1015 (India2015)|