Patent Application
20130126168
1. Field of the Invention
This invention is for a fluid jet cutter for tubular shaped items or materials. The apparatus is designed so as to be not physically attached to the item being cut. It can be used to cut tubular items or solid items. In one embodiment of the invention, the apparatus is particularly suitable for cutting tubulars such as casing as it is withdrawn from an oil or gas well.
2. Description of Related Art
U.S. Pat. No. 7,621,321 discloses apparatus for removing casing form a well by drilling two holes 450 and 440 into the casing and cutting the casing in about forty foot increments. The casing would then be raised another forty feet and the cutting and hole drilling process is repeated. U.S. Pat. No. 4,900,198 discloses apparatus for removing piles from the ground which includes fluid cutting jets 16, 17, and 19, 20. U.S. Pat. No. 6,827,145 discloses a device for pulling and cutting casing which includes clamp member 140 for engaging casing section 200. A mechanical cutting tool such as band saw 120 is used to sever the casing.
The invention disclosed herein includes an apparatus which is not required to be attached to the tubular and is adjustable to accommodate tubulars of varying diameter. The apparatus is not prone to producing great amounts of heat since the fluid acts as a coolant. Furthermore there are no sparks formed nor any open flames that could cause explosion in an explosive gas environment as is sometimes the case in an oil or gas well environment.
Referring to the drawings, an embodiment of the cutting apparatus 50 includes a main housing 63 that is open ended at the top and includes two apertures 30 and 31 in its bottom 8. Main housing 63 also includes an upwardly extending side wall 9. Four adjustable support legs 22 are fixedly secured to the main housing 63. Legs 22 each include two telescoping sections 33 and 34 with apertures 37 and 38 and locking pins 39 for adjusting the length.
An annular bearing 3 is positioned around aperture 31. An annular locking ring 4 is attached to the bottom portion of a cup shaped spinner disc 2, The top portion of the main housing 63 is covered by a plate 10 which has an opening 41 an alignment with opening 31.
An actuator 15 is mounted on top plate 10 and is coupled to a first sprocket 6. Actuator 15 may be a hydraulic rotary actuator or any other drive mechanism to rotate sprocket 6. A second sprocket 7 is rotatably supported by bearing 3 in main housing 63. Sprockets 6 and 7 are interconnected by roller chain 5. A seal retainer 1 surrounds aperture 31. A cup shaped spinner disc 2 is secured to sprocket 7. Disc 2 has an opening 43 to accommodate the tubular to be cut. A top cover disc 11 having an aperture 44 is secured to spinner disc 2 and consequently rotates with it and second sprocket 7. One or more swing arm nozzle supports 17 are adjustably secured to top cover disc 11 by bolts 18, for example, one for each jet nozzle assembly 16. By loosening a bolt 18, a swing arm nozzle support 17 can be pivoted about the bolt to a different position. The bolt can then be tightened. Each jet nozzle assembly 16 is fixedly secured to one of the swing arm nozzle supports 17 by a pair of hex bolts 19, for example. Although two nozzle assemblies 16 are shown, one or more assemblies may be used.
A top guard plate 21 having opening 46 is secured to the top cover disc 11 and spaced therefrom by suitable spaces 20. High pressure fluid is supplied to each nozzle assembly by a flexible hose not shown.
The operation of the embodiment of invention is as follows. The apparatus can be mounted on a device for pulling casing out of a well for example in such a manner that the casing would pass through openings 31, 41, 44, 43, and 46. It is understood however that the apparatus 50 may be utilized in conjunction with any tubular or solid item where it is desired to sever a portion of the tubular or solid item. Hydraulic rotary actuator is turned in a controlled manner so as to rotate first sprocket 6 as shown in
Although the present invention has been described with respect to specific details, it is not intended that such details should be regarded as limitations on the scope of the invention, except to the extent that they are included in the accompanying claims.
