Information
-
Patent Grant
-
6749392
-
Patent Number
6,749,392
-
Date Filed
Thursday, February 22, 200123 years ago
-
Date Issued
Tuesday, June 15, 200420 years ago
-
Inventors
-
-
Examiners
Agents
- Areaux; Raymond G.
- Velez; Lisa
-
CPC
-
US Classifications
Field of Search
US
- 414 626
- 414 620
- 414 800
- 294 8154
- 294 816
- 294 8161
- 294 90
- 294 111
- 294 112
- 294 106
- 294 1101
- 294 8616
- 294 8121
- 294 8151
- 294 117
-
International Classifications
-
Abstract
A quick connect/disconnect tank lifting brace which lifts a tank from an overhang of it's top lid or cover. The brace includes a crossbar, preferably adjustable, with pivotal end clamps at opposite ends of the crossbar. A pair of clamp pivoting assemblies are provided. Each clamp pivoting assembly pivots a respective one of the pivotal end clamps between an open position and a closed position and biases the pivotal end clamp to an open position for quick connection and disconnection. Pivoting is accomplished using an actuating rod parallel to the crossbar and coupled to the pair of pivoting assemblies. Articulation of the actuating rod effectuates, in unison, pivoting of each pair of pivot arms via the pivoting assemblies to a closed position. The pivoting assemblies generally utilize a push to close and pull to open motions.
Description
TECHNICAL FIELD
The present invention relates to lifting devices and, more particularly, to a quick connect/disconnect tank lifting brace for rapidly lifting and transporting heavy tanks such as used in the oil field environment offshore or onshore.
BACKGROUND OF THE INVENTION
At times, during drilling operations, drill cuttings and other debris or waste cannot be simply discarded into the water. As a result, during drilling operations efforts are undertaken to discard the drill cuttings and other debris or waste (hereinafter sometimes referred to as “drill cuttings”).
Depending on the hole size, penetration rate and the depth of the hole, tens to thousands of barrels of drill cuttings are produced. Depending on the size of the tank, a tank may store between 13½ to 25 barrels of drill cuttings. The “real estate” in the offshore oil field environment is very limited. Thus, the drill cuttings must be hauled from the offshore platform and discarded onshore. However, there is still the problem of limited real estate that can be used on the offshore platform/rig/dock for storage tanks.
It is estimated that drilling costs approximately $2,000 to $10,000 per hour. Therefore, there are numerous attempts to reduce the duration of the drilling operations even if over time a mere hour is saved. As can be appreciated, offshore platforms or rigs used in deep water drilling are more costly by virtue of their distance from land, depth to the earth's surface, etc.
Presently, the tanks employed in drilling operations have eyelets or padeyes at the corners of the tanks for coupling the lifting cables to the tank. Coupling the lifting cables to the eyelets (padeyes) or other discretely positioned couplers, affixed to the tank, could be performed rapidly if four laborers were present at each corner to connect and subsequently disconnect the lifting cables from the eyelets (padeyes) or other discretely positioned couplers. As can appreciated, this is prohibitive and a waste of valuable labor.
Most often, one to two men are used to couple a sling to the corner eyelets or padeyes of the tank. The total tank turnaround time to lift, via a crane, and connect the sling to a tank, transport the tank, disconnect the sling and return the sling to the next tank takes approximately fifteen (15) minutes per tank. With current technology, a tank can be filled with 25 barrels of drill cuttings in approximately five (5) minutes. Thus, at times, the drilling operations are limited to the tank turnaround time in which these tanks can be removed and replaced using one (1) crane.
I predict that the turnaround time for the quick connect/disconnect tank lifting brace of the present invention is approximately seven (7) minutes or about one-half the turnaround time of the sling. This is particular advantageous for drilling the top of a wellhole since, at the top of the wellhole, more drill cuttings are generated.
As will be seen more fully below, the present invention is substantially different in structure, methodology and approach from that of prior lifting devices.
SUMMARY OF THE INVENTION
The preferred embodiment of the quick connect/disconnect tank lifting brace of the present invention solves the aforementioned problems in a straight forward and simple manner.
Broadly, what is provided is a quick connect/disconnect tank lifting brace for use with a tank with a top lid or cover having an overhang. The tank lifting brace comprises an adjustable crossbar having distal ends and two pivotal end clamps wherein each end clamp is pivotally coupled to a respective one of the distal ends. A pair of clamp pivoting assemblies is included wherein each clamp pivoting assembly pivots a respective one of the pivotal end clamps via a pair of pivot arms. Pivoting is accomplished via a threaded actuating rod parallel to the adjustable crossbar and coupled to the pair of pivoting assemblies wherein rotation of the threaded actuating rod effectuates, in unison, pivoting of each pair of pivot arms via the pivoting assemblies.
In view of the above, an object of the present invention is to provide a quick connect/disconnect tank lifting brace with a pair of clamp pivoting assemblies which are spring biased via a spring biasing force for biasing the end clamps to an open position. Thus, in operation, when the quick connect/disconnect tank lifting brace (without a tank) is being lifted by a crane or hoist via lifting cables, the force exerted by the lifting cables onto the clamp pivoting assemblies does not significantly overpower the spring biasing force and thus leaves the jaws (the end clamps) essentially open and suitable for clutching a tank. In other words, this feature allows the quick connect/disconnect tank lifting brace to remain in an open position which, when transported to the top of a tank, allows such lifting brace to easily be positioned for clamping the tank. Advantageously, when the end clamps are in a closed position, if the end clamps are not locked, the lifting force can automatically lock the end clamps and their pivotal rotation.
The present invention further contemplates a quick connect/disconnect tank lifting brace for use with a tank with a top lid or cover having an overhang comprising a crossbar having distal ends and pivotal end clamps, each end clamp pivotally coupled to a respective one of the distal ends. The brace further includes a pair of clamp pivoting assemblies, each clamp pivoting assembly pivots a respective one of the pivotal end clamps between an open position and a closed position and biases said respective one of the pivotal end clamps to said open position. Furthermore, the brace includes an actuating rod parallel to the adjustable crossbar and coupled to the pair of pivoting assemblies wherein articulation of the actuating rod effectuates, in unison, pivoting of each pair of pivot arms via the pivoting assemblies to a closed position.
The present invention further contemplates a quick connect/disconnect tank lifting brace for use with a tank with a top lid or cover having an overhang comprising a crossbar having distal ends and pivotal end clamps, each end clamp pivotally coupled to a respective one of the distal ends. The brace further includes a pair of clamp pivoting assemblies, each clamp pivoting assembly pushes to pivotally close, via a pushing motion, and, alternately, pulls to pivotally open, via a pulling motion, a respective one of the pivotal end clamps and biases said respective one of the pivotal end clamps to an open position. The motion is carried out using an actuating track mechanism coupled to the adjustable crossbar and coupled to the pair of pivoting assemblies wherein actuation of the actuating track mechanism effectuates, in unison, the pushing motion to pivot the end clamps to a closed position or the pulling motion to pivot the end clamps back to the open position.
Another object of the present invention is to provide a quick connect/disconnect tank lifting brace having end clamps with two end plates fixedly secured in parallel spaced relation via a cross pivoting rod pivotally coupled to the adjustable crossbar. Each end plate comprises a forward portion having formed therein a mouth or an opening; a central portion affixed to the cross pivoting rod; and a rear portion having a hole formed therein for attaching thereto a lifting cable.
The present invention contemplates a pair of end plates which include a central portion having a protruding arc-shaped edge which (1) defines an arc of rotation of the end clamps for rotating the mouth or opening in and out of the open and closed positions; and (2) footing for balancing the quick connect/disconnect tank lifting brace. Moreover, the mouth or opening has a generally squared “C”-shaped profile.
It is a still further object of the present invention to provide a quick connect/disconnect tank lifting brace which includes shackles for coupling lifting cables to the end clamps. Thereby, during lifting, the weight of a tank is transferred to the lifting cables to counterbalance the force exerted by the weight of the tank directly applied to the forward portions of the parallel plates.
Additionally, what is provided is a method of lifting of a tank with a quick connect/disconnect tank lifting brace comprising the steps of: positioning the quick connect/disconnect tank lifting brace over a top cover or lid of a tank; applying a pivoting force to effectuate pivoting, in unison, of end clamping members having a mouth so that an overhang of the top cover or lid is received in the mouth; and, lifting the rear-ends of the end clamping members with lifting cables affixed thereto to effectuate a lifting force to an underside of the overhang and providing a counterbalancing moment force to counterbalance the weight of the tank.
A still further object of the present invention is to provide a counterbalancing moment which compensates proportionately for the weight of the tank so that the end clamps in the closed position or the locked position, under the weight of the tank, do not rotate in a direction which would “spit-out” or otherwise unclamp or disengage the overhang of the tank.
The present invention further contemplates a method of lifting of a tank with a quick connect/disconnect tank lifting brace having end clamps, each end clamp having a central rotation section with a forward depending mouth and a dependant rear-end, and the tank having sidewalls and a top cover or lid extending beyond the sidewalls to produce an overhang. The method's second step includes first positioning the quick connect/disconnect tank lifting brace over a top cover or lid of a tank. The second step includes applying a pivoting force to effectuate pivoting, in unison, of the end clamps so that the overhang of the top cover or lid is received in the mouth. The method's third step includes lifting the rear-ends of the end clamps with lifting cables affixed thereto to effectuate a lifting force to an underside of the overhang and a counterbalancing moment force to counterbalance the weight of the tank.
The method of the present invention contemplate a second step which includes pivoting, in unison, the end clamps until a front surface of each end clamp abuts or is in direct contact with a sidewall of the tank to effectuate locking of the end clamps in a closed position.
The present invention further contemplates a method of lifting of a tank with a quick connect/disconnect tank lifting brace having end clamps, each end clamp having a central rotation section with a forward depending mouth and a dependant rear-end, and the tank having sidewalls and a top cover or lid extending beyond the sidewalls to produce an overhang. The method's first step includes applying a spring biasing force to the end clamps to maintain the mouth in an open position. The method's second step includes, during the first step, lifting and maneuvering the quick connect/disconnect tank lifting brace with a lifting force less than the spring biasing force. The lifting force is substantially equal to the weight of the lifting brace. Thus, the heavier the lifting brace, the more the spring biasing force. The method's third step includes, during the second step, positioning the quick connect/disconnect tank lifting brace over a top cover or lid of a tank. The method's fourth step includes applying a pivoting force to effectuate pivoting, in unison, of the end clamps so that the overhang of the top cover or lid is received in the mouth. In other words, the jaws (the end clamps) are clamped down. The method's fifth step includes lifting the rear-ends of the end clamps with lifting cables affixed thereto to effectuate a lifting force to an underside of the overhang and a counterbalancing moment force to counterbalance the weight of the tank.
In view of the above objects, it is a feature of the present invention to provide a quick connect/disconnect tank lifting brace which is relatively simple structurally and thus simple to manufacture, operate and maintain.
Another feature of the present invention is to provide a quick connect/disconnect tank lifting brace which is durable and strong.
A further feature of the present invention is to provide a quick connect/disconnect tank lifting brace which is adapted to save time and cost, associated with oilfield operations, through the reduction in time to accomplish the connection and disconnection of the brace to and from a tank used to discard drill cuttings or other waste and debris.
An advantage of the present invention is the spring biasing of the end clamps to an open position. Thus, when connecting the brace of the present invention, a laborer does not have to waste time opening the end clamps so that they may be subsequently coupled around an overhang of a tank. The spring biasing keeps the end clamps open while the lifting brace is being positioned over the tank and allows the end clamps to be quickly closed.
A further advantage of the present invention is the removal of any play in the pivoting assemblies so that the minimum number of revolutions of the threaded actuating rod is needed for the pivotal rotation of the pivotal end clamps in and out of the closed and open positions.
The above and other objects and features of the present invention will become apparent from the drawings, the description given herein, and the appended claims.
BRIEF DESCRIPTION OF DRAWINGS
For a further understanding of the nature and objects of the present invention, reference should be had to the following detailed description, taken in conjunction with the accompanying drawings, in which like elements are given the same or analogous reference numbers and wherein:
FIG. 1
illustrates a side view of the quick connect/disconnect tank lifting brace of the present invention in an open position;
FIG. 2
illustrates a top view of the quick connect/disconnect tank lifting brace of the present invention;
FIG. 3
illustrates a side view of the quick connect/disconnect tank lifting brace of
FIG. 1
deployed on top of a tank and with lifting cables attached to the end clamps;
FIG. 4
illustrates a cross-sectional view along the plane of
4
—
4
of
FIG. 1
;
FIG. 5
illustrates a side view of the quick connect/disconnect tank lifting brace of
FIG. 3
with the end clamps in a partially closed position;
FIG. 6
illustrates a side view of the quick connect/disconnect tank lifting brace of
FIG. 3
with the end clamps in a closed position and with a lifting force applied thereto; and,
FIG. 7
illustrates a cross-sectional view along the plane
7
—
7
of FIG.
2
.
DESCRIPTION OF THE EXEMPLARY EMBODIMENT
Referring now to
FIGS. 1-5
, the quick connect/disconnect tank lifting brace of the present invention is designated by the reference numeral
10
. In the preferred embodiment, the tank lifting brace
10
is constructed and arranged to be placed on the top lid or cover of tank
5
. The lid or cover of tank
5
includes an overhang
5
a
from which the tank
5
is to be lifted. The tank
5
is adapted to be loaded and unloaded from an oil well platform or rig, dock, barge or other water vessel. In the preferred embodiment, the lid or cover of tank
5
has corner padeyes (eyelets) or discrete position couplers (NOT SHOWN) which are commonly found on lifting tanks suitable for use in the oil field. The padeyes provide a secondary means of lifting the tank
5
if necessary. Furthermore, in operation, the corner padeyes (eyelets) provide a safety mechanism or corner stoppers to prevent the lifting brace
10
from sliding off of the tank
5
in the event of an imbalance. The tanks
5
also include spaced vertical supports
4
on the sidewalls of the tank
5
. The spaced vertical supports
4
provide another safety feature, as will be described in more detail later.
The quick connect/disconnect tank lift brace
10
includes an adjustable crossbar member
20
having pivotal end clamps
30
a
and
30
b
coupled to distal ends of the adjustable crossbar member
20
. The tank lifting brace
10
further includes clamp pivoting assemblies
50
and
50
′, each clamp pivoting assembly
50
or
50
′ includes a pair of pivot arms
52
a
and
52
b
, respectively, coupled to end clamp
30
a
or
30
b
, respectively, and a threaded actuating rod
40
aligned parallel to the adjustable crossbar member
20
and coupled to the two clamp pivoting assemblies
50
and
50
′. During connection or disconnection, rotation of the thread actuating rod
40
effectuates, in unison, pivoting of each pair of pivot arms
52
a
and
52
b
via the clamp pivoting assemblies
50
and
50
′, respectively.
In the exemplary embodiment, threaded actuating rod
40
is rotated via a handle member
61
. When the handle member
61
is rotated, threaded actuating rod
40
is rotated accordingly to effectuate the pivoting motion of the pivotal end clamps
30
a
and
30
b
in unison between an open position and a closed position, depending on the direction of rotation. With respect to the handle member
61
, the handle member
61
may be substituted with a wheel. Additionally, the handle member
61
, wheel, or threaded actuating rod
40
may have a means to connect an impact gun or other electric air or hydraulic powered device thereto so that threaded actuating rod
40
could be rotated via a mechanical device instead of manual power. Although, not shown, in the preferred embodiment, brace
10
is equipped with two handle members
61
secured to opposite ends of threaded actuating rod
40
. Therefore, during connection or disconnection, a laborer would have access to either side.
While the exemplary embodiment illustrates a threaded actuating rod
40
, the threaded actuating rod
40
functions as a track which will be seen more clearly from the detailed description of the overall operation of the clamp pivoting assemblies
50
and
50
′. Other tracking means could be substituted for the threaded actuating rod
40
.
Adjustable crossbar member
20
includes two mated sections
21
a
and
21
b
wherein one end of mated section
21
b
is adapted to slide in one end of mated section
21
a
to adjust the length of the adjustable crossbar member
20
. The free ends of the mated sections
21
a
and
21
b
have attached thereto end clamps
30
a
and
30
b
, respectively. The two mated sections
21
a
and
21
b
are secured to a selected length via a fastener
22
such as a screw or bolt and nut. The mated sections
21
a
and
21
b
include holes which are adapted to be aligned so as to couple the fastener
22
therethrough.
The free ends of the mated sections
21
a
and
21
b
have fixedly secured to the distal ends thereof guide members
25
a
and
25
b
, respectively. The guide members
25
a
and
25
b
are perpendicular to the adjustable crossbar member
20
, as best seen in FIG.
1
. These guide members
25
a
and
25
b
assure that the crossbar member
20
is essentially parallel to the overhang
5
a
of tank
5
. Thereby, the pivotal rotation of the end clamps
30
a
and
30
b
to the clamping position around overhang
5
a
is not compromised.
Referring now to the end clamps
30
a
and
30
b
, since they are identical, only one end clamp
30
a
will be described in detail. End clamp
30
a
includes two (a pair of) plates
31
fixedly secured in parallel spaced relation via pivot rod member
33
(
FIG. 4
) and coupler
27
, as best seen in FIG.
4
. The profile of end clamp
30
a
is best seen in
FIGS. 1
,
3
,
5
, and
6
. The forward portion
35
a
of each of the plates
31
includes a fixed mouth or opening
32
dimensioned to receive therein the overhang
5
a
of tank
5
when end clamp
30
a
is in the clamping position, as best seen in FIG.
6
. The end clamps
30
a
and
30
b
are the primary means of securing of tank lifting brace
10
to tank
5
.
The fixed mouth or opening
32
has a generally squared “C”-shaped profile. The term “squared ‘C’-shaped profile” is used to define a “C”-shape which is less curved and wherein at least the top and bottom interior surface
32
a
and
32
b
of the “C”-shaped profile is generally straight. Moreover, the forward lower exterior surface
32
c
is also generally straight.
The profile of each plate
31
further includes a central portion
35
b
and a rear portion
35
c
. The central portion
35
b
is pivotally coupled to the adjustable crossbar member
20
via pivot rod member
33
. The rear portion
35
c
has formed therein an eyelet (padeye) or hole
37
or other means for securing a lifting cable
7
thereto. In the exemplary embodiment, a shackle
39
is secured in the eyelet or padeye
37
.
The central portion
35
b
of each parallel plate
31
has a protruding arc-shaped edge
35
b
′ which defines an arc of rotation of the end clamp
30
a
for rotating the mouth or opening
32
in and out of the open and closed positions. Moreover, the protruding arc-shaped edge
35
b
′ provides the footing for balancing the quick connect/disconnect tank lifting brace
10
on top of tank
5
. In other words, the protruding arc-shaped edge
35
b
′ provides a rocking surface from where the end clamp rocks, rotates or transitions between the open and closed positions while the lifting brace
10
is sitting on top of tank
5
. While the lifting brace
10
can be clamped to the tank
5
without resting the lifting brace
10
on the top of tank
5
, in operation (especially on vessels in heavy seas), it may be advantageous to rest the lifting brace
10
on the tank
5
and let the cables
7
go slack.
The protruding arc-shaped edge
35
b
′ has a forward edge portion which has a portion thereof which is integral with the top interior surface
32
a
of the “C”-shaped profile of the mouth or opening
32
. The protruding arc-shaped edge
35
b
′ also has a rear edge portion, the end of which merges into the rear portion
35
c
such that the rear portion
35
c
is elevated above the protruding arc-shaped edge
35
b′.
As best seen in
FIGS. 3
,
5
and
6
, during lifting in the direction of ARROWS
3
and
3
′, the weight of the tank
5
is transferred to the lifting cables
7
. The lifting cables
7
, during the tank lifting operations, provide a lifting force to the rear portion
35
c
and a counterbalancing moment force to counterbalance the force exerted by the weight of tank
5
directly applied to the forward portion
35
a
. Moreover, as the lifting brace
10
is lifted, the protruding arc-shaped edge
35
b
′ is lifted off of the top lid or cover of tank
5
as well as the top interior surface
32
a
. Instead, the bottom interior surface
32
b
of the mouth or opening
32
engages the underside of the overhang
5
a
. Thus, a gap G is created between the top lid or cover and the underside of the crossbar
20
.
Additionally, in the preferred embodiment, the width of each clamp pivoting assemblies
50
or
50
′ (that is, the distance between the outside edges of the paired (two) parallel plates
31
or
31
′, respectively) is limited to the distance between two adjacent vertical supports
4
. Hence, if an unbalanced condition exists, the load exerted by tank
5
may cause the lifting brace
10
to slide along the overhang
5
a
in the fixed mouth or opening
32
. If the clamp pivoting assemblies
50
and
50
′ are in the locked position, the vertical supports
4
will limit the slippage to the area within any two adjacent vertical supports
4
. Moreover, if the brace
10
would slip to one side or toward the corner eyelets or padeyes, the corner eyelets or padeyes obstruct the brace
10
from slipping completely off of the tank
5
.
Referring now to
FIG. 4
, in the exemplary embodiment, the end clamp pivoting assembly
50
includes two pivot arms
52
a
adapted to move in unison from an angled position (
FIGS. 1 and 3
) to a substantially vertical position (FIG.
6
), a first bearing block
56
, second slidable block
59
and spring-biased members
58
biasing the second slidable block
59
to the first bearing block
56
. The end clamp pivoting assembly
50
further includes sleeve
57
having one distal end affixed or welded to the first bearing block
56
. The other distal end has an end stop plate or flange
57
a
. The center of the first bearing block
56
has secured thereto, a threaded bushing
53
which engages the threads of the threaded actuating rod
40
. Thus, during rotation of the threaded actuating rod
40
, the first bearing block
56
tracks side to side along (that is, either toward the end of, or the center of, respectively) the threaded actuating rod
40
. Hence, the threaded actuating rod
40
is an exemplary tracking mechanism for the first bearing block
56
. In general, the first bearing block
56
functions to push and pull the spring biased second slidable block
59
via the tracking mechanism. In the direction away from the center rod support block
70
, the first bearing block
56
directly pushes second slidable block
59
. In the other direction (that is, toward the center rod support block
70
), the first bearing block
56
pushes on the tension springs
58
c
, which pushes on the screw nut
58
a
which pushes screw shaft
58
b
causing the screw shaft
58
b
to pull the spring biased second slidable block
59
by the screw head
58
d.
Each pivot arm
52
a
has a top end
55
a
and a bottom end
55
b
. The bottom end
55
b
is affixed to the exterior concentric cylinder
37
a
to allow pivot arm
52
a
to pivot or rotate about concentric cylinder
37
b
. The exterior concentric cylinder
37
a
is also affixed to the central portion
35
b
so that the pair of parallel plates
31
and pivot arms
52
a
are parallel and rotate in unison. The interior concentric cylinder
37
b
is coupled to the adjustable crossbar member
20
. The interior concentric cylinder
37
b
serves as a stationary axle on which the exterior concentric cylinder
37
a
rotates. The two concentric cylinders
37
a
and
37
b
have pivot rod member
33
journalled therethrough along a central axis. One distal end of the pivot rod member
33
is coupled to one of the parallel plates
31
and the other distal end is coupled to the other parallel plate of the pair of parallel plates
31
.
The top end
55
a
of the pair of pivot arms
52
a
is pivotally coupled to second slidable block
59
via bolting member
80
. The top end
55
a
has formed therein a hole to receive and rotate on a bolt shaft of bolting member
80
.
The spring-biased members
58
includes spring biased screws having a screw nut
58
a
, a screw shaft
58
b
, a tensioning spring
58
c
helically wound around the screw shaft
58
b
and a screw head
58
d
. The tension spring
58
c
is installed on the screw shaft
58
b
between the screw nut
58
a
and the first bearing block
56
. The screw nut
58
a
may advantageously be used to adjust the bias of the tension spring
58
c
. The screw shaft
58
b
is slidably coupled through the first bearing block
56
and the second slidable block
59
to bias the second slidable block
59
to the first bearing block
56
. Moreover, the spring biasing force eliminates any play between the first bearing block
56
and the second slidable block
59
when the lifting cables
7
are relaxed so that a more rapid disconnection to the open position can be achieved. In particular, if the end clamps
30
a
and
30
b
were not completely closed prior to lifting (i.e., prior to exerting a lifting force on the rear end
35
c
), then when disconnecting the lift brace
10
from the tank
5
, the spring biasing force tends to urge the end clamps
30
a
and
30
b
to “pop open.”
Referring still to
FIG. 4
, the tensioning spring
58
c
is shown in a substantially non-compressed state. In the substantially non-compressed state, the end clamps
30
a
and
30
b
could be fully opened, fully closed or at any stage in between the fully opened and the fully closed states. In the non-compressed state, the distance or gap between the second slidable block
59
and the first bearing block
56
is the smallest. Thus, the end clamps
30
a
and
30
b
are biased upward to the open position so that, in operation when positioning the tank lift brace
10
to clutch the tank
5
, the end clamps
30
a
and
30
b
are not engaged and, thus, will not obstruct the alignment of the brace
10
on tank
5
.
Moreover, the tensioning spring
58
c
is designed to maintain the open state under the weight of brace
10
. In other words when a crane or hoist lifts the brace
10
in the open state (open position) and, thus, no tank
5
is attached, the counterbalancing force exerted by the lifting cables
7
coupled to the rear portion
35
c
does not overpower the spring biasing force of the tensioning spring
58
c
. The net affect is that the end clamps
30
a
and
30
b
do not tend to close because the spring biasing force pulls the second slidable block
59
toward the first bearing block
56
. If the spring biasing force were overpowered by the force exerted by the lifting cables
7
coupled to the rear portion
35
c
, the end clamps
30
a
and
30
b
would tend to close and the second slidable block
59
would tend to move away from the first bearing block
56
.
As best seen in
FIGS. 1 and 3
, when the end clamps
30
a
and
30
b
are not being acted upon by a lifting force exerted through the lifting cables
7
coupled to the rear portion
35
c
, the first bearing blocks
56
and
56
′ and the second slidable blocks
59
and
59
′, respectively, are relatively close to each other or, in other words, side-by-side. When the threaded actuation rod
40
is rotated in a first direction (the direction of ARROW
4
of FIG.
5
), the first bearing blocks
56
and
56
′ track along the threaded actuation rod
40
in a direction toward the rod's distal ends. Thus, the first bearing blocks
56
and
56
′ push the second slidable blocks
59
and
59
′, respectively, as the first bearing blocks
56
and
56
′ track along the threaded actuation rod
40
. As the second slidable blocks
59
and
59
′ are pushed toward the rod's distal ends, pivot arms
52
a
and
52
b
, respectively, are pushed and pivoted so that the end clamps
30
a
and
30
b
are pivoted in the direction of ARROWS
1
and
1
′, respectively, to the closed or locked position, as best seen in FIG.
6
. In other words, the pivot arms
52
a
and
52
b
are pivoted (or rotated) from an angled position to substantially a vertical position.
The end clamp pivoting assemblies
50
and
50
′ each have a built-in fail safe feature. The feature is designed to insure that the end clamps
30
a
and
30
b
do not close beyond a certain point. While lifting the tank
5
, the end clamps
30
a
and
30
b
are prevented from “over” closing by limiting the travel of the second slidable block
59
by a stop plate
57
a
, as further described.
With reference to only the pivoting assembly
50
, sleeve
57
is generally cylindrical with an interior diameter greater than the diameter of the threaded actuating rod
40
to provide for unobstructed movement therein by such rod
40
. Moreover, +the sleeve
57
has a length which terminates at the end stop plate or flange
57
a
. Thus, if the threaded actuating rod
40
is not rotated enough so that the end clamps
30
a
and
30
b
are in a locked position (i.e., fully closed) (FIG.
6
), as the counterbalance force exerted by the lifting cables
7
force (rotate) the end clamps
30
a
and
30
b
to the locked position, the first bearing blocks
56
and
56
′ will remain generally stationary or fixed while the second slidable blocks
59
and
59
′, respectively, slide along in the direction of ARROWS
2
and
2
′, respectively, toward the stop plate or flange
57
a
and
57
a
′ or until the locked state or fully-closed position is achieved. As can be appreciated, as the distance increases between the first bearing block
56
and
56
′ and the second slidable blocks
59
and
59
′, respectively, the tensioning springs
58
c
and
58
c
′ compress.
The tension of the biasing force of the tension springs
58
c
advantageously permits for some controlled slack or play (in comparison to
50
and
50
′ without springs
58
c
and
58
c
′) so that, during rotation of the threaded actuating shaft
40
, pivotal rotation of the end clamps
30
a
and
30
b
is essentially immediate and direct while accounting for various forces at work on
50
and
50
′(more direct as the tensioning springs
58
c
and
58
c
′ become more compressed). The tension or biasing force created by the above arrangement allows the disconnect or the pivoting of the end clamps
30
a
and
30
b
to the open position to be easier especially if the end clamps
30
a
and
30
b
were not fully closed when rotating the threaded actuating rod
40
for lifting. Thus, the disconnect time to unwind and lift the end clamps
30
a
and
30
b
is reduced because the end clamps
30
a
and
30
b
tend to “pop open.” Moreover, the tension or biasing force is relatively strong to avoid transferring certain loads which would be experienced by the threaded actuating rod
40
from end clamps
30
a
and
30
b
.
FIGS. 1
,
3
,
5
and
6
illustrate possible positions of the pairs of pivot arms
52
a
and
52
b
and the end clamps
30
a
and
30
b.
The brace
10
is designed to lift a filled tank
5
having an intended weight of 25,000 lbs. However, the brace
10
is designed to lift filled tanks much greater than 25,000 lbs. In some instances, the tank itself weighs approximately 2500 lbs. Ideally, during operation, the end clamps
30
a
and
30
b
when in their clamping or closed position would abut the sidewalls of the tank
5
, as best seen in
FIG. 6
, so as to effectuate locking of the end clamps
30
a
and
30
b
. In other words, the forward lower exterior surface
32
c
of the mouth or opening
32
of each end clamps
30
a
and
30
b
is in surface-to-surface contact with the sidewall of the tank
5
.
However, if the laborer did not fully lower end clamps
30
a
and
30
b
(so that they were locked in their locked position), as the tank
5
is lifted, the pairs of pivot arms
52
a
and
52
b
would tend to automatically pivot to the locked position without mechanical damage to the clamp pivoting assemblies
50
and
50
′.
As can be appreciated, the biasing force created by the spring-biased members
58
enhances the performance by tending to keep open the end clamps
30
a
and
30
b
during the connection and alignment of the brace
10
and to permit rapid disconnection through the minimization of the number or revolutions necessary for opening the end clamps
30
a
and
30
b.
Referring now to
FIG. 7
, a cross-sectional view of the center rod support block
70
is shown. The center rod support block
70
is substantially coupled in the center or in close proximity to the center of the adjustable crossbar member
20
. The center rod support block
70
supports threaded actuating rod
40
substantially parallel to the underlying adjustable crossbar member
20
. The center rod support block
70
includes a base
71
and a upper rod guide
72
supported by the base
71
a predetermined distance above crossbar member
20
. The rod guide
72
is sandwiched between two resilient Teflon washers or buffers
74
. The rod guide
72
includes a center aperture
72
a
which is larger than the circumference of the threaded actuating rod
40
. Therefore, the threaded actuating rod
40
is allowed to move, during its rotation, within the area of the center aperture
72
a
as the end clamps
30
a
and
30
b
are pivoted to and from the open and closed positions. In closing and opening the end clamps
30
a
and
30
b
, the threaded actuating rod
40
will tend to move away (up) from the crossbar member
20
when the end clamps
30
a
and
30
b
are being closed; and, the threaded actuating rod
40
will tend to move toward (down) the crossbar
20
when the end clamps
30
a
and
30
b
are being opened.
In the exemplary embodiment, threaded actuating rod
40
includes a first threaded rod section
41
and a second threaded rod section
42
. The threaded rod sections
41
and
42
are oppositely threaded—one left and the other right. The center rod support block
70
includes a rod coupler
76
with a pin
76
a
for securing one end of the first threaded rod section
41
therein. The second threaded rod section
42
has one end affixed to the rod coupler
76
in a manner similar to the first threaded rod section
41
. However, the pin is not shown. The first threaded rod section
41
extends from the rod coupler
76
to the clamp pivoting assembly
50
. The length of the first threaded rod section
41
and the second threaded rod section
42
extends beyond the rotational plane of the end clamps
30
a
and
30
b
to provide the necessary clearance for the rotation of the handle
61
without interference. The threaded rod
42
further includes two washers
77
a
and
77
b
positioned on the exterior sides of the two resilient Teflon washers or buffers
74
.
The threaded actuating rod
40
is adapted to be extended in length by inserting an extension coupler (NOT SHOWN) between the first threaded rod section
41
and rod coupler
76
.
METHOD
The present invention contemplates the use of the quick connect/disconnect tank lifting brace
10
in the oil field environment for rapid loading and offloading of tanks, whether filled or unfilled. Nevertheless, the quick connect/disconnect tank lifting brace
10
can be used on barges, on docks, and in warehouses. The quick connect/disconnect tank lifting brace
10
is designed to be quickly connected to a tank
5
either on an oil field platform or on a water vessel and subsequently disconnected after the tank
5
has been lifted and transferred between the platform and the vessel. Additionally, the tank
5
may be lifted to or from a barge, a dock, an onshore platform, etc.
The present invention intends to position the quick connect/disconnect tank lifting brace
10
along a centerline of the tank
5
so that the tank
5
is balanced during the lifting and transport. The tank
5
preferably includes an overhang
5
a
or the like so that the mouth
32
of the pivotal end clamps
30
a
and
30
b
would be capable of receiving the overhang
5
a
or the like.
During connection or disconnection, all that is essentially required is the rotation of the handle member
61
by a single laborer and a hoist to connect to the lifting cables
7
. As the handle member
61
is rotated in a first direction, both pivotal end clamps
30
a
and
30
b
would be lowered or rotated in unison from a spring-biased open position. Once the pivotal end clamps
30
a
and
30
b
are lowered or rotated to a closed or locked position, the lifting cables
7
, lift the tank
5
via a hoist or crane (NOT SHOWN)
Since, the tank lift brace
10
does not connect to eyelets (padeyes) or other discretely positioned couplers time savings can be achieved during both connection and disconnection. During disconnection, as the handle member
61
is rotated in a second direction, both pivotal end clamps
30
a
and
30
b
would be raised or rotated to an open position simultaneously. Thereafter, the tank lift brace
10
could be raised and immediately moved and placed on another tank.
In summary, the method of lifting of a tank
5
with the quick connect/disconnect tank lifting brace
10
comprises the step of positioning the quick connect/disconnect tank lifting brace
10
over a top cover or lid of a tank
5
. Preferably, the lifting brace
10
is positioned over the centerline of the tank
5
. Moreover, prior to position the lifting brace
10
over the top cover or lid of the tank
5
, the length of the adjustable crossbar member
20
may require adjustment.
After, the lifting brace
10
has been positioned, the method includes applying a pivoting force to effectuate pivoting, in unison, of end clamps
30
a
and
30
b
having a mouth
32
so that the overhang
5
a
of the top cover or lid is received in the mouth
32
. Thus, the lifting brace
10
is effectively secured to the tank
5
. Thereafter, the method includes lifting the rear portion of the end clamps
30
a
and
30
b
with lifting cables
7
affixed thereto to effectuate a lifting force to an underside of the overhang
5
a
and a counterbalancing moment force to counterbalance the weight of the tank
5
.
In a preferred embodiment, the pivoting step includes pivoting, in unison, the end clamps
30
a
and
30
b
until a front surface (the forward lower exterior surface
32
c
) of each end clamp
30
a
and
30
b
abuts or is in direct contact with a sidewall of the tank
5
to effectuate locking of the end clamps
30
a
and
30
b
. In the preferred embodiment, the end clamps
30
a
and
30
b
should be locked prior to lifting. Thus, the pivoting should terminate when the end clamps
30
a
and
30
b
are locked.
When lifting the tank
5
, the lifting step may include attaching the lifting cables
7
to a hoist or crane (not shown).
In another preferred embodiment, if the end clamps
30
a
and
30
b
are not locked, during lifting of the tank
5
, the end clamps
30
a
and
30
b
will become automatically locked such as through the end stop plates or flanges
57
a
and
57
a
′, respectively. Alternately, the end clamps
30
a
and
30
b
will continue rotating until the front surface (the forward lower exterior surface
32
c
) of each end clamp
30
a
and
30
b
abuts or is in direct contact with a sidewall of the tank
5
to effectuate locking. By not fully locking the end clamps
30
a
and
30
b
prior to lifting, it can take less time to connect and disconnect the tank
5
, thus increasing the overall efficiency of the lifting operation.
It should be noted that during the positioning step, the method includes applying a spring biasing force to the end clamps
30
a
and
30
b
to maintain the mouth or opening
32
in an open position. Moreover, during the disconnect of the brace
10
, the method includes applying the spring biasing force to the end clamps
30
a
and
30
b
while pivoting the end clamps
30
a
and
30
b
to an open position or state.
In general, the pivoting assemblies
50
and
50
′ operate to open and close the end clamp
30
a
and
30
b
via push to close and pull to open motions along a tracking mechanism or the threaded actuating rod
40
.
It is noted that the embodiment of the quick connect/disconnect tank lifting brace and method of use described herein in detail, for exemplary purposes, are of course subject to many different variations in structure, design, application and methodology. Because many varying and different embodiments may be made within the scope of the inventive concept(s) herein taught, and because many modifications may be made in the embodiment herein detailed in accordance with the descriptive requirements of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in a limiting sense.
Claims
- 1. A method of lifting of a tank with a quick connect/disconnect tank lifting brace having end clamps, each end clamp having a central rotation section with a forward depending mouth and a dependent rear-end and the tank having sidewalls and a top cover extending beyond the sidewalls to produce an overhang, comprising the steps of:(a) positioning the quick connect/disconnect tank lifting brace over said top cover of the tank; (b) during the step of (a), applying a spring biasing force to the end clamps to maintain the mouth in an open position; (c) applying a pivoting force to effectuate pivoting, in unison, of the end clamps so that the overhang of the top cover is received in the mouth wherein the end clamps are linked together via a threaded rod having two ends which are oppositely threaded; and the step (c) includes the step of: (c1) rotating the threaded rod about one end of the two ends to effectuate said pivoting; (d) lifting the rear-ends of the end clamps with lifting cables affixed thereto to effectuate a lifting force to an underside of the overhang and providing a counterbalancing moment force to counterbalance the weight of the tank; and (e) after the step (d), applying the spring biasing force to the end clamps while pivoting the end clamps in a direction opposite the pivoting of the step (c).
- 2. The method of claim 1, wherein the step of (c) further comprises the step of:(c2) pivoting, in unison, the end clamps until a front surface of each end clamp abuts or is in direct contact with a sidewall of the tank to effectuate locking of the end clamps in a closed position.
- 3. The method of claim 1, further comprising the step of:(f) locking, in unison, each of the end clamps.
- 4. The method of claim 3, wherein the locking step (f) is complete upon the termination of step (c).
- 5. The method of claim 1, wherein:the step (a) comprises the steps of: (a1) lifting the quick connect/disconnect tank lifting brace with the lifting cables coupled to the rear-ends via a hoist, and (a2) lowering the quick connect/disconnect tank lifting brace with the lifting cables via the hoist; and the step (d) comprises the step of: (d1) lifting the lifting cables via the hoist.
- 6. The method of claim 1, wherein the step (a) includes positioning the quick connect/disconnect tank lifting brace along a centerline of the tank.
- 7. The method of claim 1, further comprising the step of:(f) prior to positioning the lifting brace over the top cover of the tank, adjusting the length of the lifting brace to accommodate the tank.
- 8. A method of lifting of a tank with a quick connect/disconnect tank lifting brace having end clamps; each end clamp having a central rotation section with a forward depending mouth and a dependent rear-end and the tank having sidewalls and a top cover extending beyond the sidewalls to produce an overhang, comprising the steps of:(a) applying a spring biasing force to the end clamps to maintain the mouth in an open position; (b) during the step (a), lifting and maneuvering the quick connect/disconnect tank lifting brace with a lifting force less than the spring biasing force; (c) during the step (b), positioning the quick connect/disconnect tank lifting brace over said top cover of the tank; (d) applying a pivoting force to effectuate pivoting, in unison, of the end clamps so that the overhang of the top cover is received in the mouth; and, (e) lifting the rear-ends of the end clamps with lifting cables affixed thereto to effectuate a lifting force to an underside of the overhang and providing a counterbalancing moment force to counterbalance the weight of the tank.
- 9. The method of claim 8, wherein the step of (d) comprises the step of:(d1) pivoting, in unison, the end clamps until a front surface of each end clamp abuts or is in direct contact with a sidewall of the tank to effectuate locking of the end clamps in a closed position.
- 10. The method of claim 8, further comprising the step of:(f) locking, in unison, each of the end clamps.
- 11. The method of claim 10, wherein the locking step (f) is complete upon the termination of step (d).
- 12. The method of claim 8, wherein:the step (b) comprises the steps of: (b1) lifting the quick connect/disconnect tank lifting brace with the lifting cables coupled to the rear-ends via a hoist, and (b2) lowering the quick connect/disconnect tank lifting brace with the lifting cables via the hoist; and, the step (e) further includes the step of: (e1) automatically locking with the lifting force the end clamps.
- 13. The method of claim 8, further comprising the step of:(f) after the step (e), applying the spring biasing force to the end clamps while pivoting the end clamps in a direction opposite the pivoting of the step (d).
- 14. The method of claim 13, wherein:the end clamps are linked together via a threaded rod having two ends which are oppositely threaded; and the step (d) includes the step of: (d1) rotating the threaded rod about one end of the two ends to effectuate said pivoting.
- 15. The method of claim 8, further comprising the step of:(f) prior to positioning the lifting brace over the top cover of the tank, adjusting the length of the lifting brace to accommodate the tank.
- 16. A method of lifting of a tank with a quick connect/disconnect tank lifting brace having end clamps, each end clamp having a central rotation section with a forward depending mouth and a dependent rear-end and the tank having sidewalls and a top cover extending beyond the sidewalls to produce an overhang, comprising the steps of:(a) positioning the quick connect/disconnect tank lifting brace over said top cover of the tank; (b) applying a pivoting force to effectuate pivoting, in unison, of the end clamps so that the overhang of the top cover is received in the mouth until a front surface of each end clamp abuts or is in direct contact with a sidewall of the tank to effectuate locking of the end clamps in a closed position; and, (c) after step (b), lifting the rear-ends of the end clamps with lifting cables affixed thereto to effectuate a lifting force to an underside of the overhang and providing a counterbalancing moment force to counterbalance the weight of the tank.
- 17. The method of claim 16, wherein:the step (a) comprises the steps of: (a1) lifting the quick connect/disconnect tank lifting brace with the lifting cables coupled to the rear-ends via a hoist, and (a2) lowering the quick connect/disconnect tank lifting brace with the lifting cables via the hoist; and the step (c) comprises the step of: (c1) lifting the lifting cables via the hoist.
- 18. The method of claim further comprising the steps of:(d) during the steps of (a1) and (a2), applying a spring biasing force to the end clamps to maintain the mouth in an open position; and, (e) after the step (c), applying the spring biasing force to the end clamps while pivoting the end clamps in a direction opposite the pivoting of the step (b).
- 19. The method of claim 16, wherein:the end clamps are linked together via a threaded rod having two ends which are oppositely threaded; and the step (b) includes the step of: (b1) rotating the threaded rod about one end of the two ends to effectuate said pivoting.
- 20. The method of claim 16, wherein the step (a) includes positioning the quick connect/disconnect tank lifting brace along a centerline of the tank.
- 21. The method of claim 16, further comprising the step of:(d) prior to positioning the lifting brace over the top cover of the tank, adjusting the length of the lifting brace to accommodate the tank.
- 22. A method of lifting of a tank with a quick connect/disconnect tank lifting brace having end clamps, each end clamp having a central rotation section with a forward depending mouth and a dependent rear-end and the tank having sidewalls and a top cover extending beyond the sidewalls to produce an overhang, comprising the steps of:(a) applying a spring biasing force to the end clamps to maintain the mouth in an open position; (b) during the step (a), lifting and maneuvering the quick connect/disconnect tank lifting brace with a lifting force less than the spring biasing force; (c) during the step (b), positioning the quick connect/disconnect tank lifting brace over said top cover of the tank; (d) applying a pivoting force to effectuate pivoting, in unison, of the end clamps so that the overhang of the top cover is received in the mouth wherein the end clamps are linked together via a threaded rod having two ends which are oppositely threaded, and the step (d) includes the step of: (d1) rotating the threaded rod about one end of the two ends to effectuate said pivoting; and, (e) after step (d), lifting the rear-ends of the end clamps with lifting cables affixed thereto to effectuate a lifting force to an underside of the overhang and providing a counterbalancing moment force to counterbalance the weight of the tank.
- 23. The method of claim 22, wherein the step of (d) further comprises the step of:(d2) during step (d1), pivoting, in unison, the end clamps until a front surface of each end clamp abuts or is in direct contact with a sidewall of the tank to effectuate locking of the end clamps in a closed position.
- 24. The method of claim 22, further comprising the step of:(f) locking, in unison, each of the end clamps.
- 25. The method of claim 24, wherein the locking step (f) is complete upon the termination of step (d).
- 26. The method of claim 22, wherein:the step (b) comprises the step of: (b1) lifting the quick connect/disconnect tank lifting brace with the lifting cables coupled to the rear-ends via a hoist, and (b2) lowering the quick connect/disconnect tank lifting brace with the lifting cables via the hoist; and, the step (e) further includes the step of: (e1) automatically locking with the lifting force the end clamps.
- 27. The method of claim 22, further comprising the step of:(f) after the step (e), applying the spring biasing force to the end clamps while pivoting the end clamps in a direction opposite the pivoting of the step (d).
- 28. The method of claim 22, further comprising the step of:(f) prior to positioning the lifting brace over the top cover of the tank, adjusting the length of the lifting brace to accommodate the tank.
- 29. A method of lifting of a tank with a quick connect/disconnect tank lifting brace having end clamps, each end clamp having a central rotation section with a forward depending mouth and a dependent rear-end and the tank having sidewalls and a top cover extending beyond said sidewalls to produce an overhang, comprising the steps of:(a) positioning the quick connect/disconnect tank lifting brace over said top cover of the tank; (b) applying a pivoting force to effectuate pivoting, in unison, of the end clamps so that the overhang of the top cover is received in the mouth; (c) lifting the rear-ends of the end clamps with lifting cables affixed thereto to effectuate a lifting force to an underside of the overhang and providing a counterbalancing moment force to counterbalance the weight of the tank; and, (d) laterally limiting shifting of the end clamps along two opposite sidewalls.
- 30. The method of claim 29, wherein the step of (b) comprises the step of:(b1) pivoting, in unison, the end clamps until a front surface of each end clamp abuts or is in direct contact with a respective one of said two opposite sidewalls of the tank to effectuate locking of the end clamps in a closed position.
- 31. The method of claim 29, further comprising the step of:(e) locking, in unison, each of the end clamps.
- 32. The method of claim 31, wherein the locking step (e) is complete upon the termination of step (b).
- 33. The method of claim 29, wherein:the step (a) comprises the steps of: (a1) lifting the quick connect/disconnect tank lifting brace with the lifting cables coupled to the rear-ends via a hoist, and (a2) lowering the quick connect/disconnect tank lifting brace with the lifting cables via the hoist; and, the step (c) further includes the step of: (c1) automatically locking with the lifting force the end clamps.
- 34. The method of claim 33, further comprising the steps of:(e) during the steps of (a1) and (a2), applying a spring biasing force to the end clamps to maintain the mouth in an open position; and, (f) after the step (c), applying the spring biasing force to the end clamps while pivoting the end clamps in a direction opposite the pivoting of the step (b).
- 35. The method of claim 29, further comprising the step of:(e) prior to positioning the lifting brace over the top cover of the tank, adjusting the length of the lifting brace to accommodate the tank.
- 36. A method of lifting of a tank, during drilling operations, with a quick connect/disconnect tank lifting brace having end clamps, each end clamp having a central rotation section with a forward depending mouth and a dependent rear-end and the tank having sidewalls and a lid extending beyond the sidewalls to produce an overhang, comprising the steps of:(a) positioning the quick connect/disconnect tank lifting brace over said lid; (b) tracking the end clamps in unison in opposite directions along a track a distance; (c) during step (b), pivoting, in unison, of the end clamps to close the mouth so that the overhang is received in the mouth; and, (d) lifting the rear-ends of the end clamps with lifting cables affixed thereto to apply a lifting force to an underside of the overhang and providing a counterbalancing moment force to counterbalance the weight of the tank.
- 37. The method of claim 36, wherein the step of (c) further comprises the step of:(c1) pivoting, in unison, the end clamps until a front surface of each end clamp abuts or is in direct contact with a sidewall of the tank to effectuate locking of the end clamps in a fully closed position.
- 38. The method of claim 36, further comprising the step of:(e) locking, in unison, each of the end clamps, wherein said locking is complete upon the termination of step (c).
- 39. The method of claim 36, herein:the step (a) comprises the steps of: (a1) lifting the quick connect/disconnect tank lifting brace with the lifting cables coupled to the rear-ends via a hoist, and, (a2) lowering the quick connect/disconnect tank lifting brace with the lifting cables via the hoist; and the step (d) comprises the step of: (d1) lifting the lifting cables via the hoist.
- 40. The method of claim 39, further comprising the steps of:(e) during the steps of (a1) and (a2), applying a spring biasing force to the end clamps to maintain the mouth in an open position; and, (f) after the step (d), applying the spring biasing force to the end clamps while pivoting the end clamps in a direction opposite the pivoting of the step (c).
- 41. The method of claim 39, wherein:the track comprises a threaded rod having two ends which are oppositely threaded; and the step (b) includes the step of: (b1) rotating the threaded rod a number of revolutions about one end of the two ends to track the end clamps the distance; the step (c) includes the step of: (c1) rocking the end clamps about a rocking surface of the end clamps.
- 42. The method of claim 41, further comprising the steps of:(e) during the steps of (a1) and (a2), applying a spring biasing force to the end clamps to maintain the mouth in an open position to minimize said number of revolutions during the rotating step (b1); and, (f) after the step (d), applying the spring biasing force to the end clamps to minimize a number of revolutions in a direction opposite said number of revolutions during the step (b1).
- 43. The method of claim wherein:the step (b) comprises the step of: (b1) while tracking, pushing the end clamps to close the mouth; and, the step (c) comprises the step of: (c1) rocking the end clamps on a rocking surface of the end clamps.
- 44. The method of claim 43, further comprising the step of:(e) limiting the distance of step (b) to prevent over closing of the end clamps.
- 45. The method of claim 43, further comprising, after the step (d), the steps of:(e) tracking a second distance, in unison, the end clamps in opposite directions along said track; (f) during step (e), pivoting, in unison, of the end clamps to open the mouth.
- 46. The method of claim 45, wherein:the step (e) comprises the step of: (e1) while tracking, pulling the end clamps to open the mouth; and, the step (f) comprises the step of: (f1) rocking the end clamps on the rocking surface of the end clamps.
- 47. The method of claim 36, further comprising the step of:(e) limiting the distance of step (b) to prevent over closing of the end clamps.
- 48. The method of claim 36, further comprising the step of:(e) prior to positioning the lifting brace over the lid, adjusting the length of the lifting brace to accommodate the tank.
- 49. The method of claim 36, wherein steps (a), (b), (c) and (d) are performed while the drilling operations are performed offshore.
- 50. The method of claim 36, wherein steps (a), (b), (c) and (d) are performed while the drilling operations include drilling a top of a wellhole.
- 51. The method of claim 36, wherein steps (a), (b), (c) and (d) are performed while the drilling operations are performed during high seas.
- 52. The method of claim 36, wherein steps (a), (b), (c) and (d) are performed while the drilling operations are performed in an oil field environment.
- 53. The method of claim 36, wherein steps (a), (b), (c) and (d) are performed while the drilling operations produce drill cuttings.
- 54. The method of claim 36, further comprising the step of:(e) laterally limiting shifting of the end clamps along the sidewalls.
- 55. The method of claim 36, wherein the step (a) comprises the step of:(a1) guiding, with guide member, the quick connect/disconnect tank lifting brace about said tank to position the end clamps to a clamping position.
- 56. The method of claim 36, further comprising the steps of:(e) prior to step (a), applying a spring biasing force to the end clamps to maintain the mouth in an open position; and, (f) during the step (e), lifting and maneuvering the quick connect/disconnect tank lifting brace with a lifting force less than the spring biasing force.
- 57. The method of claim 56, wherein the lifting force is substantially equal to the weight of the lifting brace.
- 58. The method of claim 57, further comprising the step of:(g) adjusting the spring biasing force.
US Referenced Citations (37)
Foreign Referenced Citations (3)
Number |
Date |
Country |
2576007 |
Jul 1986 |
FR |
5-294593 |
Nov 1993 |
JP |
6-144769 |
May 1994 |
JP |