JPS59110900A - Pump suspender for lng storage facility - Google Patents

Abstract

PURPOSE:In a pump suspender where a pump arranged at the lower end of conduid inserted into a tank from above can be lifted by a hoist, to improve safety upon breaking of suspending rope by lifting the pump through two suspension ropes to be wound over independent hoist. CONSTITUTION:A pump 3 for opening a valve 5 when mounting on a float valve 5 provided at the lower end is inserted into a conduit 2 to be inserted into a tank 1 of LNG storage facility from above, while lower ends of suspension ropes 10A, 10B having upper ends hooked to a hook 11 at the upper portion of conduit 2 are coupled to the pump 3. When lifting the pump 3 for the purpose of inspection, a trolley 14 travelling over a beam 8 is positioned above said conduit 2 then the cover 9 is removed to couple the suspension rods 10A, 10B to drums 21A, 21B of drum systems 13A, 13B. Then each drums 21A, 21B are rotated in opposite directions by air engines 20A, 20B to wind suspension ropes 10A, 10B to lift the pump 3.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a pump lifting device in an LNG storage facility;
For details, see LP stored in tanks built underground.
This relates to a device that takes out a pump installed near the bottom of a tank to the ground to pump up G.

As an example of an LNG storage facility, as shown in part of Figure 1.2.3, multiple conduits 2 are inserted vertically into a tank 1 constructed underground, and these pipes reach near the bottom of the tank. There is one in which a pump 3 is installed at the bottom end. The pump 3 is a submerged motor pump, and is mounted on a foot valve 5 at the lower end of the conduit 2, and its weight opens the valve.

That is, since the pump 3 is placed in an extremely low temperature atmosphere, it is often necessary to take it out to the ground for inspection. Therefore, a support 6 is installed upright on the side of the tank 1, and this support 6
The base end of a girder 8 extending in the horizontal direction is attached to a pivot shaft 7 disposed along the axis of rotation, and the pump 3 is hoisted up by a hoist installed on the girder 8 so as to be movable. First, nitrogen gas is injected into the conduit 2, LNG is discharged from the conduit 2, and in the first stage, the support cable 4 is engaged with the chain block 12 of the hoist, the pump 3 is raised a little by hand, and the foot valve 5 is closed. After this, the lid 9 of the conduit 2 is removed, and the suspension cable that is attached near the top of the conduit 2 is pulled out and connected to the body of a winding machine such as a winch of a winding machine or a hoist, and the pump 3 is hoisted to the ground using power. Take it out. At this time, the support ropes 4 are pulled manually and taken out one by one to the ground.

Conventionally, there was only one hanging rope, and if it were to lean and get caught in the conduit 2 while the pump 3 was being hoisted up, there was a concern that it would break and cause an accident in which the pump 3 would fall.

The present invention was invented for the purpose of solving these problems and providing a lifting device that can safely and stably lift a pump installed at the lower end of a conduit in a T/NG storage facility. It is.

In order to achieve this object, the present invention provides an L L system in which a pump is installed at the lower end of a conduit inserted vertically into a tank, and a hoist for hoisting the pump is placed above the tank.
In the NG storage facility, two winding drum devices each comprising an air prime mover and a drum equipped on the hoisting machine, and a pressure air circuit connecting the two air prime movers in parallel.

The gist of the invention is a lifting device comprising two hanging ropes connected to the pump and wound separately around the two bodies.

Embodiments of the present invention will be described below with reference to the drawings.

As shown in a part of Figure 1.2.3, two hanging rods 10A and IOB are connected to the bomb 3, and their upper ends are attached to the hook 11K near the upper end of the conduit 2. It is hung. The winding machine installed in the first digit 8 also includes a trolley 14 having a chain block 12 that can run independently and two winding drum devices 13A and 13B,
The wheels 15, the driving motor 16, and the overload detector in contact with the girder 8 having an I-shaped end surface are attached to the trolley frame 17, and the binion 1 meshes with the rack 18 formed on the lower surface of the girder 8.
The winding drum devices 13A and 13B in which the trolley 14 runs along the girder 8 by being driven by the traveling prime mover 16 are air prime movers 20A and 20B.
and cylinders 21A and 21B, which are mounted on a mounting frame n in parallel and with their centers of rotation aligned above the water surface, and the air motor 2
The power of the OA and 20B is transmitted to the cylinders 21A and 21 via brakes 23A and 23B and reducers built into the cylinders 21B and 21B.
Both ends of the cylinders 21A and 21B are rotatably supported by a mounting frame n, which is suspended below the trosoi frame 1f.

The traveling prime mover 16 and the turning prime mover 46 of the girder 8
Pneumatic engines are also used. The two air motors 2OA and 20B of the winding drum device 1313 are of the same type IB.

FIG. 5 shows the main parts of the pressurized air circuit, including a main air supply path with a filter U, a pressure reducing valve 5, two air supply lines g27. ．． 27B and two directional control valves 28A,
28B, and two branch exhaust passages 29A connected to these directional control valves 28A, 28B.

29B joins the main exhaust path I and is open to the atmosphere.

Each directional control valve 28A, 28B is connected to each pneumatic motor 20A, 2
Supply/discharge path 3 having speed controller 31 at two supply/discharge ports of 0B
2A1°"2A2.32Bt and 32B2, and the air resistances of the two systems for supplying and discharging pressurized air to the two air motors 20A and 20B are made to be equal to each other.

The directional control valves 28A, 28B operate the two air motors 20A, 20B in the pump lifting direction at the positions shown in FIG. 5, and when the pumps descend, the positions change in conjunction with each other, and the air motors 2OA, 20B reverse.

In addition, when an overload or swirling condition occurs, the two directional control valves 28A and 28B are activated by a signal from the overload detector Akara.
is in the off state and the air prime mover 20A.

It is trying to stop 20B.

In this embodiment, the lid 9 of the conduit 2 is removed and the suspension ropes 10A and 10B are connected to the trunks 21A and 21B, respectively.
These trunks 21A and 21B are rotated in opposite directions to connect the two hanging ropes 10A and IOB to each trunk 21A.
t 2'B K is pulled up and the pump 3 is lifted up and taken out to the ground.

The hoisting machine 33 is placed above a predetermined conduit 2 and lifts and lowers the pump 3, but in reality, the center of suspension of the pump 3 is eccentric to the midpoint N-N between the two bodies 21A and 21B. In many cases, the tensions TA and TB acting on the two hanging ropes 10A and 10B are different.

Fig. 6 is a diagram explaining the situation, where e is the eccentricity of the suspension center of the load W, and when each dimension is expressed as shown in the diagram, 'l'n=W(c+e)(c-e)'' +TF
/ 2. The relationship between e, TA, and TB is shown in a graph as shown in FIG. However, θ=tu c/
j.

FIG. 8 is a graph showing the relationship between the load W and the lifting or hanging speed 9.
< When TB, the length of the hanging rope 10B in the section becomes longer due to the winding drum device, the eccentricity e decreases, and TA=T.
It can be seen that the hanging center is automatically corrected so that it becomes B.
When the pump 3 that has been inspected is suspended from the lower end of the conduit 2, the suspension center is automatically corrected.

As described above, according to the present invention, the pump is hoisted by two hanging ropes, so even if one of the hanging ropes breaks, the pump can be easily dropped, and the other hanging rope can be used to lift it up to the ground without any trouble. It can be taken out. The two suspension ropes were individually wrapped around two bodies driven by pneumatic motors, and the pneumatic motors were connected in parallel to the pressure air circuit, so that the two pneumatic motors were connected in parallel. When a difference in load occurs, the amount of pressurized air supplied to these will automatically change to automatically control the two slings so that they are wound around the trunk with the same tension and the same amount of winding, and further winding of the slings. Even if the center and the suspension center of the pump are eccentric, the suspension center is automatically corrected, and the pump can be lifted and lowered safely and stably in a narrow conduit.

[Brief explanation of the drawing]

The drawings illustrate embodiments of the invention. Fig. 1 is a schematic plan view, Fig. 2 is a partially cutaway schematic front view, Fig. 3 is a vertical sectional view of the conduit, Fig. 4 is an enlarged partial side view, and Fig. 5 is a schematic plan view.
The figure shows the main circuit diagram of pressurized air. Figure 6 is a diagram explaining the effect when the suspension center is eccentric, Figure 7 is a graph showing the relationship between the eccentricity of the suspension center and the tension of the suspension cable, and Figure 8 is a graph showing the relationship between the load and lifting, and the tension of the suspension rope. It is a graph showing the relationship with lower speed. 1... Tank, 2... Conduit, 3
······pump. 10A110B... Hanging b 'Jf * 13
A, 13B... Winding drum device. 2OA, 20B... Air motor, 21A, 21
B... Torso. 33... Winding machine. 11- Figure 1

Claims (1)

[Claims] An LNG storage facility in which a pump is installed at the lower end of a conduit inserted vertically into a tank, and a hoist for hoisting the pump is placed above the tank, comprising an air prime mover equipped on the hoist and a shell. comprising two winding drum devices, a pressure air circuit connecting the two pneumatic motors in parallel, and two suspension ropes connected to the pump and wound separately around the two drums. Features a pump lifting device.