JPS59138610A - Pinion and rack of offshore working platform - Google Patents

Abstract

PURPOSE:To reduce the weight of a rack of the titled device by a method in which a rack provided in the longitudinal direction of a cord constituting the legs of an offshore working platform is made up by fixing a contact material to two plates at a given pitch and also by fitting the contact material with a pinion. CONSTITUTION:A rack 20 is made up by welding contact materials 22 of high- tensile steel, etc., at a given pitch P to plates 21 provided with a spacing to a cord 10 constituting the legs 4 of a bottom-landing type offshore working platform. Since a space S is formed between the plates 21, the weight of the rack 20 is reduced and the amount of expensive material such as high-tensile steel, etc., to be used in the rack is reduced. The manufacturing cost of the rack can thus be lowered.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a pinion rack mechanism that constitutes a lifting device for a bottom-mounted offshore work platform.

1! The elevating device of most of the offshore work platforms, ie jack-up rigs, in operation in Sumisekai is a rack-and-pinion system.

The rack for this equipment is normally manufactured by cutting it out from a 1/2 inch board, but the weight of the platform supported through the -ion rack is enormous, and including the incidental equipment, the weight of the platform is enormous.
．． 000). TJL uses high tensile strength steel for its material, type II. The purpose of using high-strength steel is to support the huge stacking as described above, and to eliminate the stacking of the legs themselves.

On the other hand, the racks themselves weigh up to 150 tons per rig, and the weight of the high-tensile steel used is competitive, making the racks quite expensive and complicated to manufacture.

That is, the thickness of the high-tensile steel plate used to make the rack is, for example,
It is difficult to cut the thick high-tensile steel plate of the follower lever using a normal 4i machine, so gas cutting is used to soften the expansion of the rack. The surface is finished with Machining 4141. 1 Gas cutting a high-strength steel plate causes a decrease in its strength, especially the strength of the teeth, and also causes distortion in the plate itself, that is, the rack itself, and the legs that fix it, so this distortion must be corrected. work is required.

The present invention solves the drawbacks caused by the structure of the rack and pinion rack according to the conventional manufacturing method, and includes:
The objectives are (1) easy to manufacture, (3) no reduction in strength, and (4)
It is an object of the present invention to provide a rack that can reduce the usage of expensive materials as much as possible.

The structure of the present invention for achieving the above-mentioned purpose is such that a rack provided in the longitudinal direction of the cord cord that laterally tightens the legs of the bottom-type offshore work platform is attached to two plates with contact materials at a predetermined pitch. t*m so that the contact 44 and the pinion are engaged with each other.
Pinion rack 1 of the offshore workbench with a special dish
It is.

First, before a detailed explanation of the present invention, an outline of a general bottom-mounted offshore work platform will be explained.

FIG. 1 is an exploded perspective view showing the components of the offshore work platform P, including a platform 1 made of a floating body, and legs 4 inserted into holes 3 of a jack house 2 arranged around the platform 1. It is composed of a footing 5 provided at the lower part of the leg body 4, a living area 6, a helipad deck 7, an auxiliary base 8, a derrick tower 9 etc. that is erected on the auxiliary base 8.

The leg body 4 has four cords 10 (in some cases, three cords) planted in a rectangular shape, and these cords 10 are tied together by supporting members, that is, horizontal members 11 and diagonal members 12. It was composed in a danbo style. In addition, the code 10
The distance of the darkness is 8 to 10 meters, and it is quite large.

A rack 13 is provided on the two cords 10 on the inner diagonal of the cords 10, and the pinion of the jacking device in the jacking house 2 meshes with the rack 13.

FIG. 2 is a plan view showing a conventional rack and pinion, and FIG. 3 is a side view of the same.

The diameter of the cord 10 constituting the leg body 4 is approximately 1000 to 1
It has a diameter of 300nvn and is a fairly large cylindrical body.

A rack 13 made of a high-tensile plate is welded to eccentric positions on both sides of this cord 10, and a pinion 14 is welded to this rack 13.
are meshing. Although not shown, the pinion 14 is powered by a lifting device in the jack house 2, and is configured to move the pinion 14 relative to the legs 4 to move the platform 1 up and down.

The present invention is based on the above-mentioned FIGS. 2 and 315! Of the rack and pinion shown in Figure 1, this is one with an improved rack structure, and its weight lies in the fact that the part that comes into contact with the pinion is made of a welded body made of high-grade material. .

FIG. 4 is a plan view showing the main parts of the rack and pinion according to the present invention, and FIG. 5 is a side view of the same.

The rack 20 according to the present invention includes a cord 10 constituting the leg body 4.
The contact material 22 is welded at a predetermined pitch P to cypress materials 21 and 21 fixed at intervals. Therefore, a dark gap, ie, a space S, is formed between the two plates 22.

The contact material 22 is, for example, a high tensile strength I! Select one made of high-grade material such as iI. The shape of the contact material 22 may be, for example, cylindrical, cylindrical, a circular rod only on the surface that contacts the pinion, or a shape that approximates the tip of a rack. Any item may be used as long as it has the same function as the original.

The means for fixing the contact material 22 to the plate material 21 is to first fix the contact material 22 to the plate material 21.
．． 21 at a predetermined pitch P, and insert the contact material 2 into this hole.
2 may be press-fitted, and the necessary portions may be fixed by applying pressure 23. Further, working means such as press-fitting or a combination of press-fitting and welding can be employed.

Since the rack according to the present invention is configured as described above, it is possible to achieve the following effects.

(1) Contact t? Since the space S is formed between the two plates 21 and 21 that make up the rack 22, the weight of the rack 20 is reduced by at least the volume of the empty MWJS.

Specifically, in the case of the conventional racks shown in Figures 2 and 3, because they are floating over their entire width and have a uniform thickness, they weigh 1 to 4 tons per offshore platform. After that, in the case of the rack according to the present invention, the weight is 111 tons and 33 tons.
) has been quantified.

(2) As a result of the rack being made lighter and heavier as described above, the usage of high-grade materials such as high tensile strength wA used in this rack can be reduced, and the total manufacturing cost can be reduced.

(3) Furthermore, the rack 20 according to the present invention has a pinion 14
Only the contact material 22 that comes into contact with is made of high-quality material, and in order to fix this contact material 22 between the two plates 21 and 21 by means such as welding, a large amount of heating is performed during this fixing work. As a result, there is less distortion in each member, making it easier to manufacture the pinion rack 41itN, and as a result, it is possible to reduce the number of man-hours required to manufacture the offshore work platform.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view showing the main parts of a offshore work platform, FIG. 2 is a sectional view showing the main parts of a conventional rack and pinion device, and FIG. 3 is a side view of the same. FIG. 4 is a cross-sectional view showing the rack provided on the leg according to the embodiment of the present invention and the pinion meshing with the rack, and FIG. FIG. P...Bottom-mounted offshore workbench, 1...Platform, 2...Jayatsuki house, 3...
Hole, 4... Leg, 5... Footing, 10... Cord, 11... Horizontal material, 12... Diagonal material, 13... Rack,
14...Pinion. 20...Rack, 21...Plate material, 22...Contact piece, 23
...Welding points. Agent: Patent Attorney Makoto Ogawa − Patent Attorney: Ken Noguchi Patent Attorney: Kazuhiko Saishita

Claims (1)

[Claims] A rack provided on the back side of the cord material constituting the legs of the bottom-mounted offshore work platform is configured such that contact materials are fixed to two plates at a predetermined pitch, and the contact materials and pinions are engaged with each other. A pinion rack for a marine work platform that is characterized by: