Core drilling in Harrells, South Carolina
On a perfect sunny day in late Feb 2021, we set about core drilling 1-inch holes for anchor rods for some new very large transformers that were to be installed at the Baytree Solar farm in Harrells, NC. Normally core drilling a 1-inch hole in a 5-foot concrete pad is not a problem but for this project, we had to be dead on center on every one of the 8 holes we drilled that were sprawled out on the pad in a pattern that would match the holes in the metal plates that held the transformers down to the ground in case of inclement weather or another terrible disaster. Or maybe just to hold them down. The reason that the drilling had to occur is that the concrete pad upon which the transformers sit had been designed with 1-inch rebar that made up the metal caging for the structural support of the pad. A hammer drill and rebar cutter would not be the right choice for making these holes as they need to be bored strait. Making sure that every hole was dead center and drilled into the pad plumb so that the anchor rods could be installed properly. Even the slightest angle of the bit while it drilled could possibly misalign the rods with the transformer base. Naturally, to accomplish this a 9-inch torpedo level was used to plumb the machine before drilling began. To lock the base of our m-1 core bore rig down we simply used 3 sixteenths concrete screws through a custom metal washer used exclusively with our core drill rigs.
As most core drill operators routinely use wet drilling diamond core drill bits, the knowledge is in the fact the smaller a core drill bit is the more of it wears out when core drilling through large rebar. That is because the entire surface of the bit is engaged in contact with the metal rebar not allowing any concrete to grind away the bit and thus keep it sharp and good for cutting. Now one of the reasons that we had gotten this gig is that we are listed as core drillers near Fayetteville, North Carolina, which is where FT. Bragg is located.
We do a lot of work in the sandhills of NC, usually, in the summers it is hotter but in the winter it is warmer so it is a tit-for-tat trade depending on which season the event happens to be cored in. As you travel south away from the city you come across more moat-like conditions, where water stands around in small islands of ponds. That only means one thing. your getting closer to the beach. The landscape is flatter that is for sure. Once you drive past the midsection of Moore or Lee county you can tell the terrain is quite different.
We did hit dead center on every anchor location except one where we were one eight of an inch off. I feel that's not bad to hit dead center of all the other holes. The company doing the installation of the solar transformer work is based out of California. We get a lot of work from companies that come into North Carolina and need our core drilling services.