JPS58123416A - Device for detecting slant and deformation of floating roof - Google Patents

Abstract

PURPOSE:To compute the maximum sinking position, the maximum sinking amount, and the slant and deformed state of the floating roof based on the measured value from each liquid level gage, by arranging appropriate number of the liquid level gages on the central part of the floating roof and the circumferential direction thereof, and directly measuring the liquid level position with respect to the floating roof and the slant and the deflected deformed state of the floating roof. CONSTITUTION:A pluraity of wells 5 are provided along the circumferential direction of the floating roof 3 at an appropriate angle interval and at the central part of the floating roof 3. The liquid level gage 10 is provided in each well 5. The liquid level gage 10 includes a gage head 11, a wire 12, a float 13, and a transmitting device 14. The gage head 11 has a winding up mechanism of the wire 12. The position of the float 13, which follows the liquid level in the well 5, is measured by the extending amount of the wire 12, i.e., the rotating amount of the winding piece for the wire 12. The transmitting device 14 converts the liquid level position measured by the gage head 11 into an electric or pneumatic signal, and sends it to a remote monitoring room.

Description

DETAILED DESCRIPTION OF THE INVENTION The invention relates to a device for detecting subsidence, inclination and deformation of a floating roof in a floating roof tank.

For storage tanks of crude oil and volatile flammable liquids, so-called floating roof storage tanks are used, which have a roof floating above the surface of the stored liquid, in order to minimize the formation of a dangerous atmosphere due to evaporation of the stored liquid and mixing with air. It has been adopted. This type of storage tank is very large, with a floating roof diameter of 70 to 80 mm.
m or more, it is structurally difficult to avoid deflection of the floating roof itself.

In such a storage tank, if the load of a thunderbolt, especially a 4m strike, is applied to the floating machine, it will float! Roots may become deflected or generally tilted, causing portions to sink into the storage liquid. It is important to take countermeasures against the detection building, as such deflection, inclination, and subsidence can cause an extremely dangerous situation if the stored liquid becomes wet on the floating roof.

Conventionally, the following method has been adopted for this detection.

(1) WM inspectors visually check the snow accumulation on the floating roof during patrol inspections.

(21) Appropriately install detection means such as a liquid level detection switch on the floating roof to detect wet fields of stored liquid.

As shown in Figure 1 of L3J, a gauge head 1 of a type commonly used for float type liquid bending needles etc. is attached to the tank III wall 2.
It is provided at the upper or lower part (shown by the dotted line) of the roof 3, and based on the amount of protrusion of the wire 4 to be connected to the roof 3, it is cut out at multiple appropriate positions in the direction of the 413 tt circle. Subsidence is detected by comparison with the liquid level measured by a separately provided liquid level needle of the stored liquid.

(4) As shown in FIG. 2, wells 5 are installed on the floating roof 3 at a plurality of suitable positions in the circumferential direction thereof, and the wells 5 have capacitance type liquid level detection globes 6, so-called static valley level liquid level. 7 in total, and directly detects the liquid level with respect to the floating roof 3 to detect subsidence.

However, although method (1) is advantageous in that it can prevent wet rice fields from occurring, it is dangerous when there is heavy snowfall or strong winds, and it is often practically impossible to remove snow and climb to the top of the tank. There are drawbacks.

With method (2), only the presence or absence of a wet field is detected by 1 degree, and the maximum subsidence position and amount of subsidence are 4! The disadvantage is that it cannot be estimated accurately.

Method (3) is equipped with a large number of gauge heads and can remotely detect the maximum sinking position and its sinking dojin, but the structure of the detection device is very large and increases the cost. Unless a liquid level needle is provided, sinking Vt cannot be detected. In addition, there are disadvantages such as the accumulation of ice on the wire 4, which causes trouble in winding the wire 4 by the gauge head 1, and the fact that the wire 4 is measured in a bent state, resulting in a large error.

Method (4) has no moving parts and is said to be advantageous in terms of measurement spa/accuracy, but depending on the storage liquid (for example, crude oil)
It adheres to the glove 6 and forms a hardened stain, which has the disadvantage that the measurement #IIK is extremely deteriorated.

The present invention has a simple structure and can be applied to all kinds of stored liquids in view of the block shape, and can directly measure not only the maximum sinking position, sinking amount, and slope state of the floating roof, but also the deflection of the floating roof, It is an object of the present invention to provide an inclination/forming detection device that can grasp the deformation state and easily and accurately estimate the maximum sinking position, sinking amount, #ifR, and bending deformation state.

For this reason, the invention is to provide an appropriate number of 70-J-% or displacer-type liquid level gauges arranged circumferentially on the floating roof, and also to install them in the center of the floating roof so that the liquid level relative to the floating roof is measured. In order to directly measure the position, slope and deflection deformation of the floating roof, the measured values are converted into electrical or air signals and transmitted to a monitoring room at a remote location. The percentage image indicates that the maximum settlement position, maximum settlement amount, slope of the floating roof, and deformation state can be calculated based on the measured values.

Embodiments of the present invention will be described below with reference to FIGS. 3 and 4.

In Figure @3, symbols 2.3 and 5 indicate the tank side wall, floating roof, and well, respectively, as in Figures 1 and 2. A plurality of wells 5 are provided at appropriate angular intervals along the circumferential direction of the floating roof 3, and are also provided in the center of the floating roof 3, and each well 5 has a liquid level needle generally designated by the reference numeral 10. Be prepared.

The liquid level needle 10 is connected to the gauge head 11. It includes a wire 12, a float 13, and a transmitter 14. The gauge head 11 has a wire 12t) winding mechanism, and the liquid ji is
The position of the flow (following liK) 13 is determined by the amount of feed of the wire 12, that is, the rotation type of winding of the wire 12. Transmission a14#'i gauge head 1
If the device is electrical, it is preferable that it has an intrinsically safe explosion-proof structure. In other words, pneumatic means, for example, that a plurality of air passages are provided, one of the air passages is turned off, and a combination of the two is used to create a good conduction state according to a predetermined code, and this conduction state can be transmitted at a remote location. This includes a method of detecting based on changes in air pressure, etc. Such a gauge head 11 and transmitter 14 can be easily constructed using well-known techniques, and therefore will not be described in detail.

With the above-described subsidence detection device, the d11 internal meter 10 measures the liquid level on the floating roof 3, so the position of the liquid level relative to the edema 4I3 can be directly detected. Therefore, in the state shown in FIG.
If it is set to 0, the wire payout amount decreases to the ``-'' side in the case of subsidence, and increases to the ``+'' side in the 9 cases. This decrease in quantity is fixed! It is possible to directly instruct the amount of sinking and lifting of the IK edema root 3.

In this way, the gauge head 11 picks up the needle, and the good value is converted into an electrical or pneumatic signal by the transmitter and sent to the monitoring room. Therefore, in the monitoring room, the amount of subsidence in each part is measured at the same time based on the signals from each subsidence detection device! Can be detected as an L contact.

Here, since the position of well 5 is known in advance and multiple detection devices are installed, the amount of subsidence or uplift at position 6 can be measured, so using this measurement value, the position of collapse in the circumferential direction is Floating roof 3
It becomes possible to easily calculate in which direction the is inclined and whether the previously floating jl position 3 is bent upward or downward in a convex shape. Therefore, based on this result, treatment can be performed more appropriately and quickly. Although it is not particularly shown in this round, the alarm is not only issued at 9 o'clock when subsidence occurs, but also floats based on the amount of subsidence at each position! !
It is advantageous to display the state of No. 3 on a display device or the like so that the actual state can be visually grasped. When performing subsidence prevention measures, it is advantageous to carry out the measures at the maximum subsidence position. Another thin float! Appropriate measures can be taken quickly if the roots are deformed, such as by partially tilting, or by sinking or floating in the center.

FIG. 4 shows another embodiment, in which a float 20 is suspended by link members 21 and 22, and the link member 22 is pivoted about the fulcrum P by the flow following the liquid level. The liquid level position relative to the floating roof is measured based on this pivot amount θ.Also, a displacer can be used in place of the float 20 to detect changes in buoyancy due to a decrease in the draft of the displacer. It is possible. Furthermore, the float 20 may be screwed onto a fixed screw in place of the link member 21, and the relative position may be measured by rotating the float 20 along with the rise and fall of the float 20 and measuring the rotation angle.

An example of constant calculation of the settlement, inclination, and deflection deformation state of a floating roof using the above-mentioned well and float or displacer will be shown below.

5 and 6, the radius r of the floating roof with radius r6
n wells are provided at equal intervals on the circumference of Wl, W=-...Wl, W4+, , wi+ with n≧3.
, . . . Wn and a well W. is provided in the center.

In this case, it is more advantageous to install a well and a float instead of using a capacitance method and measure the relative movement of the float to the floating roof because it can prevent the crude oil in the tank from sticking to the detection part and causing errors. be.

Float using Wl-Wn! To find the 1ilD maximum inclination angle "m&X" or the maximum sinkage (or uplift) amount 241x,
r6 tan a +Z* = Z max
(') However, zo is the amount of sinking (or floating) of the center of the floating W & root.・:・ The amount of subsidence 2 of the position M on the concentric circle of radius r, and the fifth
The maximum settlement point in the figure - a construction! Plane seat 41 as axis
j x * Affiliated company with y
(2),', Z= r t, an a * coo
(#-ψ) + Zl (3) i3N4 touching 2
The central angle β of the two wells is 360' 12□ The amount of subsidence of the valley well is Zi * Z1 + 1. As Z1+z and Wi+1 as the standard of cylindrical coordinates, Wo・
・・・・・・・・・・・・・・・ (r, -〇)Wi+1
・・・・・・・・・・・・ (r, II) W1+ meaning・・
...... (r, +θ) According to equation (3), Zl = r tanα・cog(−β−ψ)+Z.

,', Zi = r tan a(cosβcosψ
-5in II sinψ)+Zo (4)Z1+1=
rtanacos(#-p)+Ze,", Zl4-t=
=rtanacoap+Zo (5)Z
144=rtan a cos(β-?>+Z.

,', Zl-1-2= r tan σ(co!1β
co@y+@1n7I@inψ) 10Z@Equation (6) (
6) Set (4) Equation (6) Equation 10 (4) Equation (8) Set (5) 1-COθβ Substituting equation (9) into equation (5), 2Zx+x-Z1+2- Zt 8r tan a c osψ =
002(1-cooβ) (Formula (7))! + (Equation 1. [I) 2 υ as shown in Equation (1), Equation (9) and Equation Uυ'lr ainβ 1- cosβ
=3 and β=120° 3 2 2□: r 3 3 3 r Z 1 +Z r+Z l 10-(13 n=4 and β; for 90° sin β=1, coo β; 0 r Zi-H+21 + -Tri4 For i=t, 2.a, 4, find four sets of Zffla

When n = 5 and β = 60', 2 r 3 Z1 + meaning + ZI Zips + 2 (----') 2 2 re I L =
@+21+g Zt )”+(2Z1-H41Z1+
t )”) “3 + (Zt+z+Zi Zips) r 3Zt+xZi+t)”+(Zi+g+Zi Zips
) Similarly, when measuring including the center settlement ii of the floating roof using the center W@2 and W1~%, rot
an tl+Zo =Zmax (1
5x=rcos(#-ψ) y=rsin(θ-ψ) z=ztanα×zo 4Z= r tan a @ C08(#-ψ)+Z
(1?) Z1=r tanαcoa(-β-
ψ)+ZZ1=r tan α(cosβcamp→s
inβsinψ)+Z@01z1+1=
r tan cos(#-de)+Z*Z14-1=r
Tan coo? +Ze
C17,14g=r tan a cos(β-
P)+Z@Z1-H=r tan a (cos 1
IIcosp-)-sinJ sinψ)+Zo
cllj expression a Uyoshi Zi-HZg C08ψ=
しυtang', II.

Substitute the expressions 〃 and @ into the expression (to) K, (Zt + r'26) = cos β (Zips - 'Ze) +
5in(r"taq"e-(Z1+x &)")"g
inβ-2coa# (Zips-2oXZt+*-Zg))
From the G1 formula tI field and the formula (to), g zm, , :='z, 10-((zi+1-z・)"+(Z
T+! -2・)2r 5inp
1-2cosji(Zips Zg XZi+t4
o)) Snow (To) The adjacent z1+, and zi+g are Zt and z
If expressed as 2, n = 3) then β = 120°1'3 1 sin β = -c o - β = - - 2 rO Zrmxfaa+ (Z I Zo)" + (Zg
-2*)"6・r 1 + (zlzu・) (Zt-Z・)) い (to) tan a
=-[(Zl-Ze) ”+(Zg Ze)”n
; 4) case 5in71eal cos β=90@Zmax=zo+ ((Zl-Z・)"+(Zr-
Z・)")i @rO Zmax4 *+-((Z 1-Zl) "+(Z
meaning-Zg) ”i′3榔r
1(Zrf・)(Zr−Z・月! 2r・−(zl−JZ, e)(zrrie)＞I(28') Furthermore, the concave or convex deformation state of the floating mIl itself is due to On the other hand, it is only necessary to consider whether one pair of ZI ZH in the diametrical direction or the pair 21 and zl in the vicinity are linear or not. If =2・−Zt, no deformation or zi −
If z·(Zo Zl, a convex shape is detected.

According to the inclination and deformation detection device K of the present invention as described above, the following effects can be obtained.・.

(By installing the detection device on the υ binding machine, the f-plane change to be measured can be measured in a small range), and the detection device can be made smaller and cheaper.

(2) It can be easily applied to existing tanks by making some modifications to the floating roots.

(3) Easily monitor dozens of tanks.

(4) By installing multiple units in the center and circumferential direction of the floating roof, it is possible to calculate the amount of settlement O1 of the floating roof, the amount of deformation, etc. at any position), and apply settlement prevention measures to the desired location. Be able to do it. Therefore, treatment can be performed quickly, easily, and accurately.

(5) Since the detection device is a float type, there are no problems with liquid adhesion or sticking.

[Brief explanation of drawings]

,l:. 11111i1 and Figure 2. Schematic diagram of the conventional O subsidence detection device. FIG. 3 is a schematic diagram of an embodiment of a device for detecting inclination and deformation of a floating am according to the present invention. FIG. 4 is a schematic diagram of another embodiment of the invention. @S Figure and Figure 6 are medical personnel showing the method of calculating measured values. 2・・・・・・－・・・・・・tanklllll13・
・・・・・・・・・・・・・・・Floating ms5・・・・・・
・・・・・・−・Well 10・・・・・・・・・・−・
・・Detection device 11・・・・・・・・・・・・・Gauge head 12・・・・・・・・・・・・・Wire 1
3-・・・・・・・・・・・・Float i4・・・・
......-... Transmitter 20...
...Float 21.22 ...Linter member

Claims (1)

[Claims] This is a device for detecting subsidence, partial inclination, total inclination, and deflection teardrop shape of a floating roof in a floating roof type tank, in which a plurality of float wells are provided in the circumferential direction of the floating roof, and a 70 - A liquid level detection device having a float or a displacer is installed in each well to measure the liquid level position relative to the floating roof at each position, and the meter #I is sent to the monitoring room using a transmitter. Or transmit it to the monitoring panel to calculate the maximum settlement and settlement amount of the floating roof, as well as the partial or total inclination and deflection deformation, and monitor it. Tilt and deformation detection device.