WorldWide Drilling Resource

19 WorldWide Drilling Resource ® JULY 2013 Hydraulic Training by J. Eric Freimuth Hydraulic Training Associates Cylinders Part 3 Flow to the cylinder relates directly to the speed in which it travels. At what speed would the piston of a 4-inch bore cylinder extend on an oil flow of 12 gpm (gallons per minute)? The solution to this is knowing the rule of thumb, which says speed is equal to incoming flow of oil in cubic inches per minute divided by the square inch area of the piston. If you have an oil flow of 12 gpm and there are 231 cubic inches in a gallon, you would multiply the two together to determine how many cubic inches are in 12 gallons per minute. 12 x 231 = 2772 cubic inches a minute Your speed would thus be 2772 divided by 12.57 which is the piston area of the 4-inch bore. This would equal 221 inches a minute. How do I find the gpm of flow nec- essary to make a 5-inch bore cylinder travel at a rate of 175 inches per minute while extending? How fast would the cylinder retract in the same oil flow if I had a 2-inch-diameter piston rod? We need to determine by multiply- ing the piston area in square inches times travel rate in inches per minute. We know the piston area of a 5-inch bore cylinder is 19.64 square inches times the travel speed of 175 equals 3437 cubic inches. Take the 3437 cubic inches and divide by 231, which is the cubic inches in a gallon, and this would equal 14.8 gallons a minute. To find the retraction speed on 14.8 gpm, the net piston area must be found. This is the full piston area minus the rod area. 19.64 square inches is the piston area and 3.1416 square inches is the rod area. This would equal 16.5 square inches. Speed is 3437 cubic inches a minute divided by 16.5 square inches. This would equal 208 inches a minute. You will notice this is much faster than extension speed at the same oil flow. As you can see, the rate of speed relates directly to the size of the area of the piston or rod end. We will further discuss the effect of flow to the cylinder speed in the next issue. Eric Eric Freimuth may be contacted via e-mail at admin@ worldwidedrillingresource.com Navigator Nation Chooses New Tagline Adapted from Information provided by Vermeer Underground Vermeer's Navigator Nation asked fans and Facebook users to aid them in creating a new tagline for their “I like my drills yellow” ad. They asked for all to, "Get your creative juices flowing and send us your ideas". After a monthlong search, Vermeer announced, via their Facebook page, Trevor Igo of Igo Boring won the contest with: I Like My Mud Flowing My Product Pulling And My Drills Yellow Remember to get your videos in for Navigator Nation’s Ultimate Operator campaign! Bumper sticker of the winning tagline.