Accession Number : AD0824445
Title : POLAR CONSTRUCTION EQUIPMENT - DRILLING TESTS IN ICE AND ICE-ROCK CONGLOMERATE.
Descriptive Note : Technical note Jul 66-Apr 67,
Corporate Author : NAVAL CIVIL ENGINEERING LAB PORT HUENEME CA
Personal Author(s) : Hoffman, Clark R. ; Moser, Earl H., Jr
Report Date : NOV 1967
Pagination or Media Count : 27
Abstract : Exploratory and construction drilling in snow, ice and frozen ground is required in polar operations but presents problems not generally encountered in normal earth and rock drilling. Safe, reliable, accurate drilling equipment is needed for construction operations at polar coastal facilities such as McMurdo Station, Antarctica, and to a lesser extent, at inland stations in the Arctic and Antarctic. A trailer-mounted rotary drilling unit with a 12-foot tower, a 4-3/4-inch tricone bit, and a special 14-inch-diameter, 9-foot-long tube drilling bit were used for wet-drilling tests in ice, and ice with inclusions and layers of volcanic sand and gravel and basaltic rock rubble near McMurdo Station, Antarctica, during the summer of Deep Freeze 67. Wet drilling with these bits in warm sea ice was satisfactory but auger drilling is more efficient where the ice is completely penetrated by the auger. The tricone bit was used to drill exploratory holes to depths up to 56 feet and the tube drilling bit was used to extract a 38-foot-long, 12-inch-diameter core in the ice-rock conglomerate, using the wet-drilling technique. Both bits also appeared suitable for construction drilling in this material.
Descriptors : , (*DRILLING, ARCTIC REGIONS), (*DRILLING MACHINES, ARCTIC REGIONS), DRILLS, ICE, ROCK, CONSTRUCTION, ANTARCTIC REGIONS, PERMAFROST.
Subject Categories : CONSTRUCTION EQUIPMENT, MATERIALS & SUPPLIES
Distribution Statement : APPROVED FOR PUBLIC RELEASE