|Title of Invention||
ASSEMBLY FOR SUPPORTING THE FLOATING ROOFS OF TANKS FOR STORING LIQUIDS
|Abstract||An assembly for supporting the floating roofs of tanks for storing liquids particularly hydrocarbons,comprises a support leg (5),a guide (7) rigidly fastened to the floating roof which it is desired to support,and a locking pin (11). The lower end (16) of the guide (7) acts as a suppotr for the floating roof when the assembly is in the operating mode.in this situatio9n,the support leg (5) has no structural fuction and may be withdrawn,and the locking pin is installed at the top of the guide (7) coaxial with the vertical axis of the guide,so as to close the orifice via which the support leg passes. When it is necessary to place the roof in the maintenance mode.the support leg is again inserted in the orifice via which the guide (7) passes and the locking pin (11)passes through the orifices (13) of plates (12) which are rigidy fastened to the top of the guide (7),which allows the assembly to be locked. The orientation of the locking pin (11) enables an operator remotely to ascertain the operating status of the floating roof.|
"ASSEMBLY FOR SUPPORTING THE FLOating roofs OF TANKS FOR STORING LIQUIDS".
FIELD OF THE INVENTION
The present invention relates to an assembly for supporting the floating roots of tanks for storing liquid products, particularly petroleum and its derivatives.
Storage tanks arc widely used in the petroleum industry and aw
essentialy to the functioning of an operational unit. They may be intended, for example for storing crudc oil, intermediate products or final products.
Given the highly volatile nature of these products, these storage tank's have a roof rapable of floating over the stored liquid, as a way of preventing the undeirable accumulation of gases between the layer of liquid and the roof
The floating roof should in no way touch the bottom of the tank, as this would risk causing damage to the installations. It is therefore necessary to limit its travel to prevent it reaching a level which is below a specific minimum height, referred ID by specialists as the "minimum operating height".
On occasions, it is necessary for the floating roof to be stationed at a specific higher level to enable workmen to enter the tank in order to carry out maintenance operations, this height being referred to by specialists as the "maintenance height".
A minimum operating height is established which prevents the rool coming into contact with the layer of sludge which is generally deposited on the floor of the storage tank. In some situations, this minimum operating height represents 20% of the total height of the storage tank. If the level of liquid stored drops bolow this height support legs of the roof touch the floor of the tank and prevent the roof from descending further.
These suppoit legs slide inside guides which are rigidly fastened to the floating rool and make it possible to adjust the operating and maintenance heights of
the floating roof. The support legs have at least two transverse orifices which an-intended to receive locking pins. The guides also have orifices for the locking pins In
fact that the support legs are in permanent contact with the product being stored throughout the period during which the tank is in operation. This significantly reduces, the service lite of the support legs, owing to the effects of the corrosion to which they
OBJECT OF THE INVENTION
The present invention proposes the use of an assembly for supporting Moating roofs which requires the use of support legs only when the roof is in maintenance mode.
Figure 2a is a detail section taken on the line C-C of Figure 2 Figure 3 is a side view of the assembly of Figure 2 which has been
adjusted to operate with the storage tank in operating mode.
Figure 4 is a side view of the assembly of Figure 2 in a position in
which the bottom of the guide is resting on the floor of the tank.
When the tank 41 is in operation, these support legs 47 have no structural function at all; they only slide inside the guides 45, and only act as element for sealing the longitudinal interior spaces of these guides 45.
in order to place the floating roof 44 in maintenance mode as shown
having been selected in the present embodiment as this is regarded as the most
suitable arrangement.The guide 7 acts as a support for the floating roof
4 when the roof has desended as far as the lowest operating position. When such a situation occurs, (he flower end 16 of the guide 7 rests on the floor 6 of the tank, as shown in Figure 4
Generally speaking, use is made of reinforcements 2 on the floor 6 at the points where the quide 7 rests, as a way of increasing the strength of the tank floor 6.
Although the assembly for supporting the floating roofs of tanks for slo.ing liquids is composed of the three principal components described above (the guide 7. the looking pin 11 and the support leg 5). the present invention makes it possible. optionally, at times to dispense with use of the support leg, which has a structural function only when the floating roof 4 is in the maintenance mode.
The flange 20 has dimensions which are greater than those of the orifices 13 and it acts as a stop limiting travel of the locking pin 11 As the stop 14 has dimensions which are greater than the dimensions of the shaft 19, as may be seen in detail in Figure 7a which is a section taken on line A-A of Fig 7, the locking pin 11 is prevented from moving longitudinally in either direction and it then acts as a stop for the support log 5, as may bo seen in Figure 6. enabling the floating roof A to be supported.
1. An assembly for supporting a floating roof of a tank for storing liquids, comprising: a guide having an upper end and a lower end, said guide being substantially hollow in the longitudinal direction thereof and being rigidly fastened to a floating roof to be supported thereby, said guide being fixed to said roof so as to extend in a direction substantially perpendicular to a plane of said roof and so that said lower end projects downwardly from a bottom surface of said roof and said upper end projects upwardly from an upper surface of said roof, whereby when said floating roof reaches a lowest position thereof within the tank, said lower end of said guide supports said floating roof; a support leg comprising a substantially vertical column sized so as to be slidably received within said hollow guide, said support leg having a first, lower end for being received into said hollow guide and a second, upper end, said support leg further comprising a first stop structure provided adjacent said second end thereof, said guide including a second stop structure complementary to said first stop structure for engaging the same to limit insertion of said support leg into said guide; a lock receptacle extending vertically upwardly from said second stop structure, said lock receptacle defining a pair of mutually aligned orifices; and a locking component for selectively engaging said lock receptacle to limit upward movement of said support leg relative to said guide; wherein said locking component comprises a main body including a handle to allow manually grasping thereof; a flange; a locking pin shaft extending in a direction generally perpendicular to a plane of said flange; a fastening structure at a free end of said locking pin shaft for selectively fastening to said second end of said support leg; and a locking pin stop adjacent said fastening structure; wherein said locking pin shaft and said locking pin stop are sized for being slidably disposed through said aligned orifices, but said flange of said locking component has a transverse dimension greater than the transverse dimension of said orifices thereby to define a travel limiter for limiting insertion of said locking component, a length of said locking pin shaft being such that when said locking pin
shaft extends through said orifices and across a space between said orifices, said locking pin stop is disposed on a diametrically opposite side of said lock receptacle with respect to said flange, whereby said locking pin shaft defines a vertical stop for said support leg that limits upward movement of said support leg relative to said guide.
2. The assembly as claimed in claim 1, wherein said lock receptacle comprises two plates, each in the form of a part cylindrical segment and each rigidly fastened at the upper end of said guide, and having said mutually aligned orifices therein.
3. The assembly as claimed in claim 1, wherein said support leg is removable from said guide and wherein with the support leg removed, said fastening structure of said locking component can be coupled to the upper end of said guide, with said flange closing an upper end orifice of said guide, so as to prevent undesired communication between an inside of said tank with an exterior of said tank.
4. The assembly as claimed in claim 3, wherein a bottom of said flange which comes into contact with the upper end of said guide is covered with a sealing material.
5. The assembly as claimed in claim 1, wherein said first stop structure has fastening structure complementary to said locking component fastening structure for fastening said locking component to said support leg.
6. The assembly as claimed in claim 5, wherein said locking component fastening structure is a threaded pin rigidly fastened to said locking pin stop, and said complementary fastening structure of said first stop structure is a threaded orifice; whereby, when it is necessary to fasten said locking component to said support leg, said threaded pin is secured into said threaded orifice.
7. The assembly as claimed in claim 5, wherein said locking component is
vertically oriented when fastened to said support leg second end and said locking
component is horizontally oriented when received in said aligned orifices whereby the
position of said locking structure gives a remote observer a visual indication of an
operational status of the assembly.
8. The assembly as claimed in claim 7, wherein said locking component is painted
with a conspicuous paint to enable it to be seen from a distance.
9. The assembly as claimed in claim 1, wherein said locking component is vertically oriented when fastened to said support leg second end and said locking component is horizontally oriented when received in said aligned orifices, whereby the position of said locking component gives a remote observer a visual indication of an operational status of the assembly.
10. An assembly according to claim 9, wherein said locking component is painted with a conspicuous paint to enable it to be seen from a distance.
|Indian Patent Application Number||380/MAS/1998|
|PG Journal Number||07/2008|
|Date of Filing||25-Feb-1998|
|Name of Patentee||PETROLEO BRASILEIRO S A- PETROBRAS|
|Applicant Address||AV REPUBLICA DO CHILE NO 65, RIO DE JANEIRO,|
|PCT International Classification Number||B 65D 88/34|
|PCT International Application Number||N/A|
|PCT International Filing date|