FULL-UNIT LIFTIING METHOD FOR QUAYSIDE CONTAINER CRANE

Abstract

A full-unit lifting method for a quayside container crane includes calculating an overall center position of gravity of the quayside container crane full-unit; estimating a lifting height and a floating amplitude required by a main hook of a floating crane according to a water level differential at a dock and a height of the quayside container crane full-unit; selecting the floating crane and obtaining detailed parameters thereof according to basic lifting conditions of the floating crane; selecting a type of the main hook according to a weight of the quayside container crane full-unit, checking whether an interference between the boom of the floating crane and the front boom occurs, and determining an inclination angle of the floating crane during lifting; calculating a load on the lifting wire rope and selecting the lifting wire rope and a shackle; making preparations before lifting; and performing lifting at the dock.

Claims

1. A full-unit lifting method for a quayside container crane, comprising following steps: step 1: calculating an overall center of gravity of the quayside container crane, comprising calculating a center of gravity of each of assemblies of the quayside container crane according to a design drawing of the quayside container crane, summarizing the centers of gravity of the assemblies of the quayside container crane into a center of gravity position table, and obtaining an overall center of gravity position (G (x, y, z)) of the quayside container crane by summing values of the centers of gravity of the assemblies of the quayside container crane in the center of gravity position table, wherein the center of gravity of each of the assemblies of the quayside container crane is calculated by defining an intersection of a left-right symmetry central plane of the quayside container crane, an upper plane of a rail and a longitudinal central plane of a waterside rail as an origin, and defining a direction of a front boom as an x-axis positive direction; step 2: estimating a lifting height and a floating amplitude required by a main hook of a floating crane according to a water level differential at a dock and a height of the quayside container crane, wherein the water level differential at the dock (h.sub.1) and the height of the quayside container crane (H) are known parameters; step 3: selecting the floating crane and obtaining parameters of the floating crane according to basic lifting conditions of the floating crane, wherein the basic lifting conditions are that a maximum lifting height of the main hook of the floating crane (h.sub.4max) is greater than the height of the quayside container crane (H)+Csin , where C is a length of a lifting wire rope and is an angle between the lifting wire rope and a horizontal plane, and the parameters of the floating crane comprise a height from a deck surface of the floating crane to a water surface (h.sub.2), a height from the deck surface of the floating crane to a lower hinge joint of a boom of the floating crane (h.sub.3), a length of the boom of the floating crane (L.sub.1), an angle between the boom of the floating crane and the horizontal plane (), the lifting height of the main hook of the floating crane (h.sub.4), a height from the main hook of the floating crane to an upper pulley at the boom of the floating crane (h.sub.5), a radius of the boom of the floating crane (R), a width of the floating crane (B), a length of the floating crane (L), and a distance from the lower hinge joint of the boom of the floating crane to a front end of the floating crane (L.sub.3), where R=L.sub.1cos , h.sub.1+h.sub.4+h.sub.5=h.sub.2+h.sub.3+L.sub.1sin , h.sub.4+h.sub.5 is a constant, h.sub.4 and h.sub.5 are not constant values, h.sub.5 has a minimum value h.sub.5min, when h.sub.5h.sub.5min, h.sub.4 reaches its maximum value h.sub.4max, step 4: selecting a type of the main hook of the floating crane according to a weight of the quayside container crane, checking whether an interference between the boom of the floating crane and the front boom occurs, and determining an inclination angle of the floating crane during lifting, comprising: when the weight of the quayside container crane exceeds 700 t, a floating crane with two main hooks is selected, wherein the length of the boom of the floating crane (L.sub.1), a distance between two lower hinge joints of the floating crane (B.sub.1), a distance between the two main hooks at an uppermost end of the floating crane (B.sub.2), a length of a straight edge of the boom of the floating crane (L.sub.2), and an angle () between an inclined edge and the straight edge of the boom of the floating crane are satisfied with $=\mathrm{arc}\frac{B_1-B_2}{2\left(L_1-L_3\right)};$ an angle between the boom of the floating crane and a dock shoreline (), a center of a connecting line between the two main hooks of the floating crane coincides with the overall center of gravity position of the quayside container crane in a top view, a height of a first main hook of the two main hooks to the dock surface (h.sub.4), and a height of a second main hook of the two main hooks to the dock surface (h.sub.4) are satisfied with h.sub.4=h.sub.2+h.sub.3+L.sub.1sin h.sub.1h.sub.5; h.sub.4=h.sub.2+h.sub.3+L.sub.1sin h.sub.1h.sub.5; a position of the first main hook is set as DG.sub.1 (x.sub.5, y.sub.5, z.sub.5), $x_5=x-\frac{B_2}{2}\sin ,y_5=y+\frac{B_2}{2}\cos ,z_5=h_4^{};$ a position of the second main hook is set as DG.sub.2 (x.sub.6, y.sub.6, z.sub.6), $x_6=x+\frac{B_2}{2}\sin ,y_6=y-\frac{B_2}{2}\cos ,z_6=h_4^{},$ assuming that in the top view, an intersection between the front boom and the boom of the floating crane is t(x.sub.t, y.sub.t, z.sub.t), it is obtained as: $y_{\text{?}}-y_{\text{?}}=\frac{B_4}{2},y_{\text{?}}=y_{\text{?}}-\frac{B_4}{2},\frac{y_{\text{?}}-y_{\text{?}}}{x_{\text{?}}-x_{\text{?}}}=\tan \left(\frac{}{2}--\right),$ $x_{\text{?}}=x_{\text{?}}+\frac{B_{\text{?}}}{2\tan \left(\frac{}{2}--\right)},$ $R^{}=\frac{y_{\text{?}}-y_{\text{?}}}{\sin \left(\frac{}{2}--\right)}\cos =\frac{B_{\text{?}}}{2\sin \left(\frac{}{2}--\right)}\cos ,z_t=z_6+h_5\text{?}{R}^{}\cot ,$ $\text{?}\text{indicates text missing or illegible when filed}$ wherein a basic condition for judging whether the interference between the boom of the floating crane and the front boom occurs is z.sub.t is greater than the height of the front boom of the quayside container crane (h.sub.6), when the interference occurs, a re-check is performed by adjusting the angle () between the boom of the floating crane and the dock, a distance (D) between the floating crane and an apron is checked, a corner point of the floating crane closest to the apron is set as n (x.sub.n, y.sub.n, z.sub.n), D is obtained by calculating x.sub.n, $x_{\text{?}}=x+\left(R-L_{\text{?}}\right)\cos \left(\frac{}{2}--\right)-\frac{B}{2}\cos ,$ $D=x_{\text{?}}-B_{\text{?}}=x+\left(R-L_{\text{?}}\right)\cos \left(\frac{}{2}--\right)-\frac{B}{2}\cos -B_{\text{?}},$ $\text{?}\text{indicates text missing or illegible when filed}$ in order to prevent the floating crane from colliding due to a fact that the floating crane is too close to the apron during lifting, D possesses a minimum safe distance, and a basic condition for determining whether a safe distance between the floating crane and the apron is enough is D>2 m; step 5: calculating a load on the lifting wire rope and making selection of the lifting wire rope and a shackle, the position of the first main hook is DG.sub.1 (x.sub.5, y.sub.5, z.sub.5), and $x_5=x-\frac{B_2}{2}\sin ,y_5=y+\frac{B_2}{2}\cos ,z_5=h_4^{},$ the position of the second main hook is DG.sub.2 (x.sub.6, y.sub.6, z.sub.6), and $x_6=x+\frac{B_2}{2}\sin ,y_6=y-\frac{B_2}{2}\cos ,z_6=h_4^{},$ positions of four lifting lugs at the quayside container crane are obtained by measuring dimensions on the design drawing as: D.sub.1 (x.sub.1, y.sub.1, z.sub.1), D.sub.2 (x.sub.2, y.sub.2, z.sub.2), D.sub.3 (x.sub.3, y.sub.3, z.sub.3), D.sub.4 (x.sub.4, y.sub.4, z.sub.4), lengths of four lifting wire ropes are respectively calculated as follows: a length of a first lifting wire rope of the four lifting wire ropes is $C_1=\sqrt{{\left(x_5-x_{\text{?}}\right)}^2+{\left(y_5-y_{\text{?}}\right)}^2+{\left(z_5-z_{\text{?}}\right)}^2},$ $\text{?}\text{indicates text missing or illegible when filed}$ a length of a second lifting wire rope of the four lifting wire ropes is $C_2=\sqrt{{\left(x_6-x_2\right)}^2+{\left(y_6-y_2\right)}^2+{\left(z_6-z_2\right)}^2},$ a length of a third lifting wire rope of the four lifting wire ropes is $C_3=\sqrt{{\left(x_5-x_3\right)}^2+{\left(y_5-y_3\right)}^2+{\left(z_5-z_3\right)}^2},$ a length of a fourth lifting wire rope of the four lifting wire ropes is $C_4=\sqrt{{\left(x_6-x_4\right)}^2+{\left(y_6-y_4\right)}^2+{\left(z_6-z_4\right)}^2},$ the height (h.sub.4) of the first main hook and the height (h.sub.4) of the second main hook are calculated by setting the length (C.sub.2) of the second lifting wire rope and the length (C.sub.3) of the third lifting wire rope, so as to obtain the length (C.sub.1) of the first lifting wire rope and the length (C.sub.4) of the fourth lifting wire rope, an then an angle () between each of the four lifting wire ropes and the horizontal plane exceeds 60, the angle () between each of the four lifting wire ropes and the horizontal plane is calculated as follows: ${}_1=\arcsin \left(\frac{z_{\text{?}}-z_{\text{?}}}{C_1}\right),{}_2=\arcsin \left(\frac{z_{\text{?}}-z_{\text{?}}}{C_2}\right),$ ${}_3=\arcsin \left(\frac{z_{\text{?}}-z_{\text{?}}}{C_3}\right),{}_4=\arcsin \left(\frac{z_{\text{?}}-z_{\text{?}}}{C_4}\right);$ $\text{?}\text{indicates text missing or illegible when filed}$ and then a load on each of the four lifting wire rope is calculated as follows: since a gravity of the floating crane is vertically downward and the center of the connecting line between the two main hooks coincides with the overall center of gravity position of the quayside container crane in the top view, a load on the first main hook and a load on the second main hook is substantially balanced, it is obtained that a vertical downward load on each of the two main hooks is $\frac{Q}{2}$ when a total weight (Q) of the quayside container crane is obtained according to the design drawing, so that the load on the first lifting wire rope, the load on the second lifting wire rope, the load on the third lifting wire rope and the load on the fourth lifting wire rope are respectively calculated with the first lifting wire rope and the third lifting wire rope sharing a first main hook while the second lifting wire rope and the fourth lifting wire rope sharing the second main hook, based on that a resultant force in a vertical direction of two of the four lifting wire ropes of one of the two main hooks is a lifting weight $\frac{Q}{2},$ and a resultant force in a horizontal direction is 0, it is obtained that $F_{\text{?}}\sin {}_{\text{?}}+F_{\text{?}}\sin {}_{\text{?}}=\frac{Q}{2},$ $\text{?}\text{indicates text missing or illegible when filed}$ F.sub.1cos .sub.1=F.sub.3cos .sub.3; $F_{\text{?}}\sin {}_{\text{?}}+F_{\text{?}}\sin {}_{\text{?}}=\frac{Q}{2},$ $\text{?}\text{indicates text missing or illegible when filed}$ F.sub.2cos .sub.2=F.sub.4cos .sub.4, the load on the first lifting wire rope, the load on the second lifting wire rope, the load on the third lifting wire rope and the load on the fourth lifting wire rope are obtained by solving equations respectively: $F_{\text{?}}=\frac{Q}{2\left(\sin {}_{\text{?}}+\cos {}_{\text{?}}\tan {}_{\text{?}}\right)},F_{\text{?}}=\frac{Q}{2\left(\sin {}_{\text{?}}+\cos {}_{\text{?}}\tan {}_{\text{?}}\right)},$ $F_{\text{?}}=\frac{Q}{2\left(\sin {}_{\text{?}}+\cos {}_{\text{?}}\tan {}_{\text{?}}\right)},F_{\text{?}}=\frac{Q}{2\left(\sin {}_{\text{?}}+\cos {}_{\text{?}}\tan {}_{\text{?}}\right)}$ $\text{?}\text{indicates text missing or illegible when filed}$ according to the load on the first lifting wire rope, the load on the second lifting wire rope, the load on the third lifting wire rope and the load on the fourth lifting wire rope, wherein a lifting wire rope having a diameter with a safety factor above 4 and a shackle with a safety coefficient above 1 are selected by referencing a wire rope breaking force table; step 6: making preparations before lifting; and step 7: performing lifting operation at the dock.

2. The full-unit lifting method for the quayside container crane according to claim 1, wherein the length of each of the four lifting wire ropes (C.sub.1-C.sub.4) is 24 m, the angle (Y) between the four lifting wire ropes and the horizontal plane is 60 at minimum, and the height of the main hook to the upper pulley at the boom of the floating crane (h.sub.5) has a minimum value (h.sub.5min) of 5 meters.

3. The full-unit lifting method for the quayside container crane according to claim 1, wherein the step 6 further comprises: before lifting, travelling a trolley to a maximum rear extension position of a rear boom, retracting an upper frame of a container hanger to a highest position of the container hanger, parking an elevator at a first floor, locking brakes of the assemblies in such a way, that the trolley and trailer trolley wheels are plugged by wedge blocks, to keep the front boom at a horizontal position; for a travelling mechanism, inserting wooden blocks at rotatable positions of eight-wheel equalizer beams and driving and driven bogies before the lifting, so as to prevent rotation; checking securing and fastening of the assemblies of the quayside container crane to ensure all movable components are fastened; disassembling all anchorages between the quayside container crane and a transport vessel; using two winches on a floating crane vessel to secure two portal legs obliquely opposite the quayside container crane before the lifting, diagonal portal legs of the quayside container crane are pulled by the two winches on the floating crane vessel after the lifting, to maintain a constant inclination angle between the floating crane and the quayside container crane.

4. The full-unit lifting method for the quayside container crane according to claim 1, wherein the step 7 of performing lifting operation at the dock further comprises: 1) after a floating crane vessel arrives at a construction site, the floating crane vessel is positioned within 200 m offshore from a quay front line, the floating crane vessel inclines, a length of an anchor cable is adjusted with reference to barge parameters and water conditions of the dock, to realize operational processes of lifting, shifting, and parking; 2) after the floating crane vessel is positioned, all tools and equipment used during the lifting are comprehensively checked, the floating crane vessel is put into use after it is confirmed that no abnormal condition exists, and whether a lifting point of the equipment is consistent with a diameter of a shackle pin or not is checked, after checking, an angle of the boom is adjusted to a required angle, all mechanical parts of the floating crane vessel are rechecked, and the floating crane vessel is used after being confirmed to be intact; 3) the floating crane vessel is lifted by the two main hooks, the two main hooks are loosened above the equipment to be lifted, rigging suspended on the two main hooks in advance is attached to lifting lugs of the equipment in sequence, and reliability of each connection point is rechecked; 4) after preparation, the lifting is performed, when the lifting is 200 mm away, all starting equipment brakes, a component is suspended on the two main hooks for secondary braking, a static state is maintained, when there is no abnormal condition, the floating crane is started to lift the component to a preset height and is suspended in a static state, the component is horizontally lifted during the lifting, to avoid uneven height discrepancies between the two main hooks; 5) after the component is lifted, a towing belt of a tugboat is used to assist in shifting to an installation berth, and anchor positioning is performed at an installation site, the floating crane vessel is repositioned after arriving at the installation site by adjusting a length and an orientation of the anchor cable, so that the floating crane is positioned above a rail of an installation dock, and the floating crane is kept descending horizontally, so that the equipment in a suspended state is aligned to a position right above a placing point by 10 cm; 6) a placing position of the equipment is approved, the floating crane is commanded to loosen the two main hooks, and the equipment is placed at the placing point; 7) lifting construction is carried out until the lifting is finished, and all lifting tools are retracted and the floating crane vessel is withdrawn.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0033] FIG. 1 is a schematic diagram of a structure of a quayside container crane full-unit according to the present application;

[0034] FIG. 2 is a schematic diagram of structural parts of the quayside container crane full-unit according to the present application;

[0035] FIG. 3 is a schematic diagram of an RO-on/RO-off process for the quayside container crane full-unit according to the present application;

[0036] FIG. 4 is a flow chart of a full-unit lifting method for the quayside container crane according to the present application;

[0037] FIG. 5 is a gravity center position table of the quayside container crane full-unit according to the present application;

[0038] FIG. 6 shows a gravity center position and a coordinate system of the quayside container crane full-unit according to the present application;

[0039] FIG. 7 schematically shows a first relevant parameter of lifting by a floating crane according to the present application;

[0040] FIG. 8 schematically shows a second relevant parameter of the lifting by the floating crane according to the present application;

[0041] FIG. 9 shows relevant parameters of a boom of the floating crane according to the present application;

[0042] FIG. 10 shows relevant parameters for determining whether the floating crane interferes with the front boom according to the present application;

[0043] FIG. 11 shows relevant parameters for determining whether there is a sufficient safe distance between the floating crane and an apron according to the present application; and

[0044] FIG. 12 is a top view of a lifting wire rope according to the present application.

DETAILED DESCRIPTION

[0045] The present application will be further described in detail below in combination with the accompanying drawings and embodiments.

[0046] Referring to FIGS. 1 to 12, a full-unit lifting method for a quayside container crane specifically includes following steps.

[0047] 1. Calculating an overall center of gravity (COG) of the quayside container crane: calculating a COG of each assembly of the quayside container crane full-unit according to a design drawing of the quayside container crane full-unit, by which an origin is defined as an intersection of a left-right symmetry central plane of the quayside container crane full-unit, an upper plane of a rail and a longitudinal central plane of a waterside rail, a direction of a front boom is defined an x-axis positive direction, summarizing the COG of the assemblies of the quayside container crane full-unit into a COG table, and obtaining the overall COG G (x, y, z) of the quayside container crane full-unit by summing values of the COG of the assemblies of the quayside container crane full-unit in the COG table.

[0048] 2. Estimating a lifting height and a floating amplitude required by a hook of a floating crane according to a water level differential at a dock and a height of the quayside container crane full-unit, by which the floating crane is selected and detailed parameters thereof are obtained according to basic lifting conditions of the floating crane, and an outline diagram of the floating crane is drawn; known parameters include the water level differential at the dock h.sub.1, the overall COG position of the quayside container crane full-unit G (x, y, z), position coordinates of four lifting lugs on the quayside container crane D1 (x.sub.1, y.sub.1, z.sub.2), D2 (x.sub.2, y.sub.2, z.sub.2), D3 (x.sub.3, y.sub.3, z.sub.3), D4 (x.sub.4, y.sub.4, z.sub.4), a height of the quayside container crane full-unit H, a height from the front boom to the plane of the rail h.sub.6, a distance from the waterside rail to the apron B.sub.3, a width of the front boom B.sub.4; relevant parameters of the floating crane include a height from a deck surface of the floating crane to a water surface h.sub.2, a height from the deck surface of the floating crane to a lower hinge joint of a boom of the floating crane h.sub.3, a length of the boom of the floating crane L.sub.1, an angle between the boom of the floating crane and a horizontal plane , a lifting height of the hook of the floating crane h.sub.4, a height from the hook of the floating crane to an upper pulley at the boom of the floating crane h.sub.5, a radius of the boom of the floating crane R, a width of the floating crane B, a length of the floating crane L, and a distance from the lower hinge joint of the boom of the floating crane to a front end of the floating crane L.sub.3, where R=L.sub.1cos , generally is 65; h.sub.1+h.sub.4+h.sub.5=h.sub.2+h.sub.3+L.sub.1sin , h.sub.4+h.sub.5 is a constant. However, since the hook may move up and down through a lifting mechanism, h.sub.4 and h.sub.5 are not constant values, h.sub.5 has a minimum value h.sub.5min which is generally set to 5 m due to a minimum safe distance between the hook and the upper pulley of the boom; when h.sub.5=h.sub.5min, h.sub.4 reaches its maximum value h.sub.4max, which is a basic condition for determining whether the floating crane may perform the lifting, namely a maximum lifting height of the hook of the floating crane h.sub.4max>the height of the quayside container crane full-unit H+a length of the lifting wire rope Csin , where C is the length of the lifting wire rope and is an angle between the lifting wire rope and the horizontal plane, generally, the length of the lifting wire rope C is taken as 24 m, and the angle between the lifting wire rope and the horizontal plane is 60 at minimum.

[0049] 3. Checking interference between the boom of the floating crane and the front boom, and determining an inclination angle of the floating crane during lifting. Since a weight of the quayside container crane full-unit typically exceeds 700 tons, the floating crane with two main hooks is required. The relevant parameters of the floating crane include the length of the boom of the floating crane L.sub.1, a distance between two lower hinge joints of the floating crane B.sub.1, a distance between two main hooks at an uppermost end of the floating crane B.sub.2, a length of a straight edge of the boom of the floating crane L.sub.2, and an angle between an inclined edge and the straight edge of the boom of the floating crane with

[00014]$-\arctan \frac{B_1-B_2}{2\left(L_1-L_3\right)};$

as the two main hooks of the floating crane are adopted for lifting, the angle between the boom of the floating crane and the dock shoreline is , a center of a connecting line between the two hooks of the floating crane must coincide with the overall COG position of the quayside container crane full-unit in the top view. The lifting heights of the two hooks may be different (with a height difference not too large). It is assumed that a height from a first hook of the floating crane to the dock surface is h.sub.4, and a height from a second hook of the floating crane to the dock surface is h.sub.4, h.sub.4=h.sub.2+h.sub.3+L.sub.1sin h.sub.1h.sub.5; h.sub.4=h.sub.2+h.sub.3+L.sub.1sin h.sub.1h.sub.5. If a position of the first hook of the floating crane is set as DG.sub.1 (x.sub.5, y.sub.5, z.sub.5),

[00015]$x_5=x-\frac{B_2}{2}\sin ,y_5=y+\frac{B_2}{2}\cos ,z_5=h_4^{};$

if a position of the second hook of the floating crane is set as DG.sub.2 (x.sub.6, y.sub.6, z.sub.6),

[00016]$x_6=x+\frac{B_2}{2}\sin ,y_6=y-\frac{B_2}{2}\cos ,z_6=h_4^{},$

assuming that in the top view, an intersection between the front boom and the boom of the floating crane is t(x.sub.t, y.sub.t, z.sub.t), the following may be obtained as:

[00017]$y_6-y_t=\frac{B_4}{2},y_t=y_6-\frac{B_4}{2},\frac{y_6-y_t}{x_t-x_6}=\tan \left(\frac{}{2}--\right),x_t=x_6+\frac{B_4}{2\tan \left(\frac{}{2}--\right)},R^{}=\frac{y_6-y_t}{\sin \left(\frac{}{2}--\right)}\cos =\frac{B_4}{2\sin \left(\frac{}{2}--\right)}\cos ,z_t=z_6+h_5-R^{}\cot ,$

and the basic condition for determining the interference between the boom of the floating crane and the front boom includes: z.sub.t>the height of the front boom of the quayside container crane h.sub.6; if interference occurs, re-check is performed by adjusting the angle between boom of the floating crane and the dock, where cannot be adjusted arbitrarily; is ensured not too small to avoid collision between a floating crane vessel and the dock, and thus it is also necessary to check a distance D between the floating crane and the apron; it is assumed that a corner point of the floating crane closest to the apron is n (x.sub.n, y.sub.n, z.sub.n), and D can be obtained by calculating x.sub.n;

[00018]$x_n=x+\left(R-L_3\right)\cos \left(\frac{}{2}--\right)-\frac{B}{2}\cos ,D=x_n-B_3=x+\left(R-L_3\right)\cos \left(\frac{}{2}--\right)-\frac{B}{2}\cos -B_3,$

in order to prevent the floating crane from colliding due to the fact that the floating crane is too close to the apron during lifting, D possesses the minimum safety distance, and the basic condition for determining whether a safe distance between the floating crane and the apron is enough is D>2 m.

[0050] 4. Calculating a load on the wire rope and selecting the wire rope and shackles; the position of the first hook of the floating crane is DG.sub.1 (x.sub.5, y.sub.5, z.sub.5) and

[00019]$x_5=x-\frac{B_2}{2}\sin ,y_5=y+\frac{B_2}{2}\cos ,z_5=h_4^{},$

the position of the second hook of the floating crane is DG.sub.2 (x.sub.6, y.sub.6, z.sub.6), and

[00020]$x_6=x+\frac{B_2}{2}\sin ,y_6=y-\frac{B_2}{2}\cos ,z_6=h_4^{},$

the positions of four lifting lugs at the quayside container crane are obtained by measuring dimensions on the drawings as: D.sub.1 (x.sub.1, y.sub.1, z.sub.2), D.sub.2 (x.sub.2, y.sub.2, z.sub.2), D.sub.3 (x.sub.3, y.sub.3, z.sub.3), D.sub.4 (x.sub.4, y.sub.4, z.sub.4); then lengths of the four lifting wire ropes are as follows: [0051] the length of a first lifting wire rope is C.sub.1={square root over ((x.sub.5x.sub.1).sup.2+(y.sub.5y.sub.1).sup.2+(z.sub.5z.sub.1).sup.2)}, the length of a second lifting wire rope is C.sub.2={square root over ((x.sub.6x.sub.2).sup.2+(y.sub.6y.sub.2).sup.2+(z.sub.6z.sub.2).sup.2)}, the length of a third lifting wire rope is C.sub.3={square root over ((x.sub.5x.sub.3).sup.2+(y.sub.5y.sub.3).sup.2+(z.sub.5z.sub.3).sup.2)}, the length of a fourth lifting wire rope is C.sub.4={square root over ((x.sub.6x.sub.4).sup.2+(y.sub.6y.sub.4).sup.2+(z.sub.5z.sub.1).sup.2)}, The heights h.sub.4 and h.sub.4 of the two hooks of the floating crane can be calculated by setting the length C.sub.2 of the second lifting wire rope and the length C.sub.3 of the third lifting wire rope, and the length C.sub.1 of the first lifting wire rope and the length C.sub.4 of the fourth lifting wire rope can be obtained; checking that the angle between each of the lifting wire ropes and the horizontal plane exceeds 60. The angle between each of the lifting wire ropes and the horizontal plane is as follows:

[00021]${}_1=\arcsin \left(\frac{z_5-z_1}{C_1}\right),{}_2=\mathrm{arc}\sin \left(\frac{z_6-z_2}{C_2}\right),{}_3=\arcsin \left(\frac{z_5-z_3}{C_3}\right),{}_4=\arcsin \left(\frac{z_b-z_4}{C_4}\right);$

The load on the lifting wire rope is calculated as follows: since the gravity is vertically downward, and since the center of the two hooks of the floating crane corresponds to the overall COG position of the quayside container crane full-unit, it can be considered that the loads on the two hooks of the floating crane is substantially balanced. A total weight Q of the quayside container crane may be known according to the design drawing, and it may be obtained that a vertical downward load on each of the hooks of the floating crane may be

[00022]$\frac{Q}{2},$

so that the load on each of the lifting wire ropes may be calculated as follows. The first lifting wire rope C.sub.1 and the third lifting wire rope C.sub.3 share one hook of the floating crane, and the second lifting wire rope C.sub.2 and the fourth lifting wire rope C.sub.4 share the other hook of the floating crane. According to that a resultant force in the vertical direction of the two lifting wire ropes of the same hook of the floating crane is a lifting weight

[00023]$\frac{Q}{2},$

and a resultant force in the horizontal direction should be 0, it may be obtained that

[00024]$F_1\sin {}_1+F_3\sin {}_3=\frac{Q}{2},$

F.sub.1cos .sub.1=F.sub.3cos .sub.3;

[00025]$F_2\sin {}_2+F_4\sin {}_4=\frac{Q}{2},$

F.sub.2cos .sub.2=F.sub.4cos .sub.4. The loads on the four wire ropes may be obtained by solving equations respectively

[00026]$F_1\frac{Q}{2\left(\sin {}_1+\cos {}_1\tan {}_3\right)},F_3\frac{Q}{2\left(\sin {}_3+\cos {}_3\tan {}_1\right)},F_2\frac{Q}{2\left(\sin {}_2+\cos {}_2\tan {}_4\right)},F_4\frac{Q}{2\left(\sin {}_4+\cos {}_4\tan {}_2\right)}$

[0052] According to the loads on the wire ropes, a wire rope having a diameter with a safety factor above 4 and a shackle with a safety coefficient above 1 are selected by referencing a wire rope breaking force table.

[0053] Specifications and lengths of the wire rope and types of the shackle and the like are compiled into a table and are in one-to-one correspondence with the lifting lugs.

[0054] Example: length parameters of the wire rope are shown in the following table:

TABLE-US-00001 position length diameter theoretical load type of shackle 1 22.6 m 150 mm 280 t 300 t 2 22 m 150 mm 330 t 350 t 3 22 m 150 mm 337 t 350 t 4 24 m 150 mm 277 t 300 t

[0055] 5. Making preparations before lifting: before the lifting, travelling a trolley to a maximum rear extension position of the rear boom (adjustable based on the specific COG position); retracting an upper frame of a container hanger to its highest position, parking an elevator at a first floor, locking brakes of respective mechanisms, plugging the trolley and trailer trolley wheels by wedge blocks, and keeping the front boom horizontal; for a travelling mechanism, inserting wooden blocks at rotatable positions of the eight-wheel equalizer beams and driving and driven bogies before the lifting, so as to prevent rotation; checking the securing and fastening of all components of the quayside container crane to ensure all movable components are fastened firmly; disassembling all anchorages between the quayside container crane and the transport vessel; using two winches on the floating crane vessel to secure two portal legs obliquely opposite the quayside container crane before lifting (through the pre-adjusted lengths of the wire ropes, rotation due to insufficient horizontal stability after the quayside container crane may be prevented after the quayside container crane is hoisted, and the diagonal legs are pulled by the winches for protection), the diagonal portal legs of the quayside container crane must be pulled by the two winches on the floating crane vessel continuously after lifting, to maintain a constant inclination angle between the floating crane and the quayside container crane.

[0056] 6. Performing lifting operation at the user dock including following steps.

[0057] 1) After the floating crane arrives at a construction site, the floating crane is positioned within about 200 m offshore from the quay front line, the floating crane inclines at a certain angle (generally, an angle between an extension direction of the boom of the floating crane and the dock is) 50, a length of an anchor cable is adjusted with reference to barge parameters and the water conditions of the dock, to ensure that operational processes of lifting, shifting, parking and the like may be achieved.

[0058] 2) After the floating crane vessel is positioned, all tools and equipment used during lifting are comprehensively checked, the floating crane vessel may be put into use after it is confirmed that no abnormal condition exists, and whether a lifting point of the equipment is consistent with a diameter of a shackle pin or not is checked. After all of the checks are performed, the angle of the boom is adjusted to a required angle. All mechanical parts of the floating crane are rechecked, and the floating crane may be used after being confirmed to be intact.

[0059] 3) The floating crane vessel are lifted by two main hooks, the hooks are loosened above equipment to be hoisted, rigging suspended on the hooks in advance is attached to lifting lugs of the equipment in sequence, and the reliability of each connection point is rechecked.

[0060] 4) After it is confirmed that the preparation work is completed, the lifting operation is performed. When the lifting is 200 mm away, all starting equipment brakes, a component is suspended on the main hooks for secondary braking, and a static state is maintained. When there is no abnormal condition, the crane is started to hoist the component to a preset height and is suspended in the static state. The object is kept horizontally hoisted and slowly lifted in the lifting process, avoiding uneven height discrepancies between the two hooks.

[0061] 5) After the component is stably hoisted, a towing belt of a tugboat is used to assist in slow shifting to the installation berth, and the component is anchored and positioned on the installation site. The floating crane vessel is repositioned after arriving at the installation site by adjusting the length and the orientation of the anchor cable. The crane is positioned above the rail of the installation dock, and kept descending horizontally and slowly, so that the equipment in the suspended state is aligned to the position right above the placing point by 10 cm.

[0062] 6) the placing position of the equipment is approved, the floating crane is commanded to slowly loosen the hooks, and the equipment is stably placed at the placing point.

[0063] 7) According to the construction process, lifting construction is carried out until the lifting is finished, and all lifting tools are retracted and the floating crane vessel is withdrawn.

[0064] The above description includes only preferred embodiments of the present application, and is not intended to limit the present application in any form, and therefore, any modifications, equivalent substitutions and improvements made to the above embodiments according to the technical principle of the present application, without departing from the scope of the technical solution of the present application, still fall within the protection scope of the technical solution of the present application.