Square drill collars accomplish four goals: (1) they provide continuous centralization over their length, (2) they maximize bending resistance (stiffness), (3) they maximize torsional damping, and (4) they minimize axial vibrations. On the down side, they are expensive to buy and to maintain. They usually create high rotary torque. They grind drill bit cuttings and cavings to fines which radically increases mud consumption. They are difficult to fish. Note that a 11.2 inches round collar has the same stiffness as a 12.125 inches square collar.
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How would you like to save a ton of money and increase the value of your home by as much as thirty percent! If your homes landscape is designed properly it will be a source of enjoyment for your entire family, it will enhance your community and add to the resale value of your property. Landscape design involves much more than placing trees, shrubs and other plants on the property. It is an art which deals with conscious arrangement or organization of outdoor space for human satisfaction and enjoyment.