Self-equalizing linkage for well derricks

Claim 2

In a hydraulic ram system for well derricks using force-producing rams paralleled in pairs, a cross-head structure for summing and transferring the forces from the heads of the rams to common load means, the structure comprising a. a pin trolley carriage restricted for translation only along a path parallel to the axes of the rams, said carriage carrying b. a pivot pin with centerline at a right angle to the plane through the axes of the rams of a pair, and positioned between said axes, and c. a cross-head beam pivotally mounted on said pin and bridging said rams to receive their forces, d. the forces being received on rolling-sliding convex faces on the said beam from each ram, said faces being located between the heads of the rams and the pivot pin, and e. common load means attached to said structure.

Claim 3

The hydraulic ram system of claim 1, in which the rams are mounted on a framework carrying vertical tracks, the tracks being parallel to the axes of the rams, and the said carriage being provided with rolling means engaging said tracks and permitting translation of the carriage along said tracks.

Claim 4

The system of claim 2, in which the convex faces on the cross-head beam are received in concave recesses in the heads of the juxtaposed rams.

Claim 5

The system of claim 2, in which the common load means includes at least one tension strut attached at upper end to the said structure, and at its lower end to a remote load.

Claim 6

The system of claim 4, in which a pair of tension struts are arranged generally parallel to the axes of the rams, and between said axes, and are each pinned at their upper ends to each of two pinning points on the cross head beam, said pinning points being at a level lower than the pivot pin level, and equidistant therefrom..

Claim 7

The system of claim 5 in which the other ends of the said pair of tension struts are bridged by a beam attached to said other ends, said beam conveying the sum of the ram forces to the remote load means.

Claim 8

The system of claim 6, in which flexible means transfers the force from the said beam to a remote load means.

Claim 9

The system of claim 7, in which the remote load means comprises a saddle device shaped to cup and support a load.

Claim 10

The system of claim 8, in which the said saddle device includes rolling elements, and tracks are mounted on said framework parallel to the axes of the rams, adapted to couple with said rolling elements, whereby linear translation of the saddle device along said tracks is produced by operation of the rams.

Claim 11

The system of claim 3, in which the convex surfaces are spherical, each with center on the axis of its ram, and of radius at least as large as the vertical distance from the cross head beam pivot pin to a line interconnecting the heads of the rams.

Claim 12

In a well-drilling derrick system utilizing hydraulic ram means for lifting power swivels, power slips, and well-pipe string along a vertical well centerline, the derrick system having a derrick framework with a face adjacent and parallel to said well centerline, the improvement comprising in operative combination:

Claim 13

In a well-drilling derrick system utilizing hydraulic ram means for lifting power swivels, power slips, and well-pipe string along a vertical well centerline, the derrick system having a derrick framework with a face adjacent and parallel to said well centerline, the improvement comprising in operative combination:

Claim 14

track means on said face parallelling said centerline; 2. pin trolley means riding on said track means and thereby limited to vertical translational movement, the pin trolley means carrying 3. a beam pivot pin with horizontal centerline intersecting said well centerline, 4. the said hydraulic ram means comprising at least one pair of similar hydraulic cylinders with rams, having ram heads, the ram centerlines parallelling the well centerline, the centerlines of each pair being equidistant therefrom, the cylinders being mounted for vertical movement of their rams adjacent said derrick face, 5. a cross-head beam means pivoted on said beam pivot pin, and bridging the said rams, and carrying 6. rolling-sliding convex bearing surfaces opposite each ram, the rolling-sliding centerpoint of each said surface being at a level at least equal to said beam pivot pin centerline, 7. the cross-head beam also carrying two strut pivot pins with centerlines parallel to the beam pivot pin and at a level lower than the levels of both the beam pivot pin and the said rolling-sliding centerpoints, the strut pivot pin centerlines being equidistant from the well centerline, and between the innermost pair of rams, the strut pivot pins supporting 8. two vertical tension struts extending downwardly from said strut pivot pins to 9. load means supporting said power swivel, power slip, and well-pipe string.

Claim 15

track means on said face parallelling said centerline; 2. pin trolley means riding on said track means and thereby limited to vertical translational movement, the pin trolley means carrying 3. a beam pivot pin with horizontal centerline intersecting said well centerline, 4. the said hydraulic ram means comprising at least one pair of similar hydraulic cylinders with rams, having ram heads, the ram centerlines parallelling the well centerline, the centerlines of each pair being equidistant therefrom, the cylinders being mounted for vertical movement of their rams adjacent said derrick face, 5. a cross-head beam means pivoted on said beam pivot pin, and bridging the said rams, and carrying 6. rolling-sliding convex bearing surfaces opposite each ram, the rolling-sliding centerpoint of each said surface being at a level at least equal to said beam pivot pin centerline, 7. the cross-head beam also carrying two strut pivot pins with centerlines parallel to the beam pivot pin and at a level lower than the levels of both the beam pivot pin and the said rolling-sliding centerpoints, the strut pivot pin centerlines being equidistant from the well centerline, and between the innermost pair of rams, the strut pivot pins supporting 8. two vertical tension struts extending downwardly from said strut pivot pins to 9. load means supporting said power swivel, power slip, and well-pipe string.

Claim 16

In a well derrick, a lever system for transferring forces from individuals in pairs of rising force-producing means to a common load comprising leverage-shifting means operating on at least one lever arm of the said lever system to decrease the lever arm of a first individual that rises faster than the second individual of its pair, whereby the rise is automatically opposed by increased loading of said first individual.

Claim 17

In a well derrick, a lever system for transferring forces from individuals in pairs of rising force-producing means to a common load comprising leverage-shifting means operating on at least one lever arm of the said lever system to decrease the lever arm of a first individual that rises faster than the second individual of its pair, whereby the rise is automatically opposed by increased loading of said first individual.

Claim 18

The system of claim 12 in which said force-producing means is at least one pair of hydraulic rams with ram heads normally rising in unison, and the said lever system is a cross head beam with arms carrying force-reception surfaces bridging said rams, pivoted on a horizontal pivot pin centered between the lines of force of said rams.