GB1423497A - Pivoted well drilling mast and separate tower - Google Patents

Abstract

1423497 Boring earth etc LEE C MOORE CORP 18 June 1974 26907/74 Heading E1F Well drilling apparatus, particularly suitable for use on a floating vessel 2, includes an open fronted drilling mast 5 which is hinged to a substructure 1 for swinging movement between a prone position (shown in full line) and an upright position (shown dotted) and an open backed pipe racking tower 16 also hinged to the substructure for swinging movement between prone and upright positions. As described the substructure 1 is provided with a gin pole 3, drawworks 10 and shoes 4 in which the feet of the drilling mast 5 are pivoted. A wire line 8 extends from the draw-works 10 around a crown block 7 and a travelling block 9. When prone the mast 5 rests on a support 6. To raise the mast 5 a sling 12 is connected to a bracket 14 on the mast 5, is passed around sheaves 13 on the gin pole 3 and is fixed to the travelling block 9. Operation of the draw-works 10 thus raises the mast 5 which is then fixed to the gin pole 3. The pipe racking tower 16 is hinged to the substructure at 17 and when prone rests on a support 18. To raise the tower 16 a sling 20 is used which is fixed at one end to a bracket 23 on the tower 16, passes around sheaves 22, 21 and is fixed at its other end to the travelling block 9. When raised the tower 16 is connected to the mast 5. The tower 16 includes pipe racking platforms 25, 26 for receiving stands of pipe and carriages 27, 28, 29 which can move along transverse tracks 30. Each carriage is provided with an arm 31 which can grip the pipe and which can be moved longitudinally to move the pipe into and out of the mast 5.