GB598512A - An improved well device - Google Patents

Abstract

598,512. Well tools. DEHN, F. B. (Baker Oil Tools, Inc.). Oct. 31, 1945, No. 28919. [Class 85] A tool for washing, cementing, acidizing or testing wells is attached at the end of a tubular string C and comprises a tubular element formed by two sections 15 and 16 held in spaced relationship by a pipe 17. The continuity of the through passage is interrupted by welded blanks 29 and 33 whilst a pair of packing pieces such as 10 and 11 are fitted at the outer ends of each tube for sealing an annular space 35 between the tubular element and the casing B. Each packing piece of a pair consists of a rubber swab mounted between a ring 18 and a thimble 19, the pairs being held apart by a spacer sleeve 25, whilst locking-nuts 21 and 22 expand the swabs against the casing B. Adjacent the innermost packing pieces 11 and 12 are two ports 36 and 37 in the tubular element, whilst at the end of the element is a control valve 38. A byepass tube 26 runs through the element and opens to the casing space above and below the sealed-off portion by T connections 28 and 32. When the tool is lowered down the casing, the ball 42 of the valve 38 is raised from the seat 41 by a pin 43 which slides up through the locking member 39 due to the friction between the casing and springs 48 so that fluid passing down the string C flows through the port 36, the annular space 35, the port 37 and the valve 38, and passes up the casing by way of the byepass 26. On reaching the desired depth, the tool is raised slightly and the valve closes, the fluid then passing out through the liner openings 14.