GB1295697A - - Google Patents

Abstract

1295697 Transfer arms; clamps COMPAGNIE FRANCAISE DE PETROLES SA 29 June 1970 [14 Nov 1969] 31452/70 Headings E1F and E2A A pivotally mounted transfer arm for transferring elongate elements 20 such as rods or tubes from one position to another comprises a beam 2 having mounted on it guides 8, 9, 10 and a clamp 11 which are displaceable laterally of the beam by jacks 13, 14, 15 and 16 and releasably engage the element. The clamp 11 is mounted on a carriage which is movable longitudinally of the beam 2 by a jack 18, and a stop 12 for supporting the element at the bottom part of the beam, Fig. 3 (not shown), can also be adjusted laterally of it by a jack 17. The positions of the supports for the guides, clamp and stop relative to the beam may be varied. The guides 8, 9, 10, Figs. 4 and 5 (not shown), are adjustable to enable them to engage rods of small diameter or tubes of large diameter. The clamp 11, has toothed jaws 42 floatably guided by inclined faces 37a of pivoted, jack-operated arms 37 and spring-biased to a central position. In operation, when the beam is inclined the weight of the element moves the jaws downwardly against the spring bias to increase the grip of the jaws on the element. The stop 12 is used with the guides 9, 10 only, when the element is heavy and of large diameter. The jack 18 is used to move the clamp arms downwardly to release the element after it has been first lowered to engage another member, Figs. 9 to 9b (not shown). The arm may be counterbalanced by a hydraulic jack having the ends of its cylinder hydraulically connected to vessels containing oil subject to nitrogen pressure which is varied by varying the quantity of oil in the vessels and so varies the counterbalancing force, Fig. 10 (not shown). The arm may be used to supply a derrick with rods stored horizontally.