GB675003A - Improvements in or relating to a portable oil well mast - Google Patents

Abstract

675,003. Portable oil well masts. MOORE CORPORATION. L. C. Nov. 22, 1949. [Dec. 3, 1948] No. 29865/49. Class 78 (iv). A portable oil well mast has upwardly converging sides, the upper portions of which are connected by rigid bracing, while the lower portions are pivotally mounted, so that their ends can be swung laterally toward each other to reduce the width of the lower portion of the mast for transportation purposes. The mast. Figs. 1 and 2, is of the type pivoted at 6 to a base 1 and raised by action of a cable 19 to rest against a gin pole formed by front and rear legs 8 and 9 respectively. The mast is of U-shape cross section, the front being open, and consists of upper and lower portions 14, 15, the back of the upper portion consisting of rigid bracing. The back of the lower portion however, consists of two bracing structures each secured to one of the sides and supporting heavy horizontal members 36 which are pivoted together at 35. This enables the lower portion, when pivots 6 on the base and connections 16, 17 to the upper portion have been removed to be deformed whereby the sides can be made parallel and the overall width is reduced to conform with highway limitations e.g. reduced to eight feet. In order to load the mast on a lorry Fig. 8, the drawworks 11 is operated to lower the mast so that the upper portion rests on the lorry. Thereafter the mast hook 21 is drawn up into the upper portion, and the cable 19 is disconnected and reattached to the lower portion. The lower portion is then detached by first removing the connections 17 which will be underneath, and then removing the upper connections so as to leave the upper portion on the lorry. The lorry is then backed as shown so the lower portion can be raised and lowered again to lie on the lorry and surround the upper portion. The pivots 6 are now removed and the sides of the lower portion made parallel so that the portions both rest on the lorry nested within each other. For deforming the lower portion, a screw jack 46 is connected between the bracing on one side and a toggle linkage 41 interconnecting a pair of brackets 39 one attached to each side. A telescoping link 48 between the toggle link and the bracing on the opposite side to that of the jack 46 is provided with a catch pin 49 to lock the sides in the position, as used, Fig. 2.