JPS6138090A - Sea bottom mounting type structure - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a submarine-based structure.

[Conventional technology]

The pillars of conventional bottom-mounted underwater structures are fixed to the structure, so if the seabed is sloping, the structure may also slope, tipping over, or being unable to perform its intended functions. be.

[Problem that the invention seeks to solve]

The present invention was proposed in view of the above circumstances, and an object of the present invention is to provide a seabed-mounted structure that can maintain a vertical posture without tilting even when landing on a sloping seabed. shall be.

[Means for solving problems]

To this end, the present invention provides a submarine bottomed structure that is attached to the seabed by a plurality of pedestals protruding from the lower end, which includes a plurality of pedestals that extend and contract using hydraulic cylinders and pistons, and a lower hydraulic pressure of each of the hydraulic cylinders. A lower communication pipe that communicates the chambers with each other, a pilot check valve connected to the upper hydraulic chamber of each of the above hydraulic cylinders, an upper communication pipe that communicates the upstream side of each of the above pilot check valves with each other, and each of the above pilot check valves. It is characterized by comprising a pilot hydraulic switching valve for controlling.

[Effect]

With such a configuration, it is possible to obtain a submarine-based structure that can maintain a vertical posture even when the pedestal lands on an inclined seabed.

〔Example〕

An embodiment in which the present invention is applied to a seabed drilling device will be explained with reference to the drawings. FIG. 1 is an overall side view of the device, and FIG.
It is a hydraulic system diagram of the pillar shown in the figure.

In the above diagram, 1 is a mother ship on the sea surface with a crane 2,
Reference numeral 4 indicates a bottom-mounted test drilling apparatus according to the present invention, and a test drilling drill 7.
It is suspended by a crane 2 via an umbilical cable 3 and is designed to land on the seabed 5.

6a+6b, 5c are three pillars protruding vertically at equal intervals from the lower end of the drilling equipment 4. The pillar 6a is driven by the piston 9a of the hydraulic cylinder 8a, and the pillar 6b is driven by the piston 9b of the hydraulic cylinder 8b. , the pillars 6C are each configured to be extendable and retractable by a piston 9C of a hydraulic cylinder 80.

10a, 10b, and IQc are hydraulic cylinders 8, respectively.
Pilot check valves 11 are inserted into hydraulic pipes connected to the upper hydraulic chambers of a, 8b, and 8c, and 11 is a pilot check valve 10a.

an upper communication pipe that communicates with each other on the upstream side of 10b and 10c;
12 is a lower communication pipe that communicates the lower hydraulic chambers of the hydraulic cylinders 8a, 8b + 80 with each other; 13 is an accumulator; when the pilot check valves 1oa+10b+10c are controlled via the electromagnetic switching valve 14 and the pilot hydraulic pipe 19, both are electromagnetic switching valves. It is connected to the vent pipe 20 via 14.

15 is an inclinometer attached to the test drilling device 4, 16a, 16b
, 16c and 1.72.17b.

17C is an upper limit inch and a lower limit inch of the pistons 9a, 9b, and 9C, respectively; 18 is a control unit that controls the electromagnetic switching valve 14; and 21 is a pressure gauge inserted into a hydraulic pipe connected to the upper communication pipe 11. be.

In such a device, the umbilical cable 3 includes a tension member for suspending the test drilling device 4, and a cable for supplying power to the prime mover and each device in the test drilling device 4, as well as transmitting and receiving signals. .

The control unit 18 also controls the pressure signal from the pressure gauge 21 and the inclinometer 15.
slope signal, upper limit switch 16a, 16b, 1
6c, lower limit switch 17a+ 17b, 17c
By switching the electromagnetic switching valve 14 based on the signal from each pilot check valve 10a + 10b
+10c is controlled.

Bottoming in such a device is performed in the following manner.

(1) When the test drilling apparatus 4 is suspended via the umbilical cable 3 and reaches near the seabed 5, the solenoid valve 14 is switched to the position shown in FIG. 2 via the control section 18.

Then, the pilot oil pressure is sent from the accumulator 13 to the pilot check valves, so each pilot check valve 10a, 10b, 10c
is in the open state, and each hydraulic cylinder 8 a t 8
b +8C upper oil chambers are in communication with each other.

(2) If the drilling equipment 4 is further lowered in this state, the bottom of the sea 5 will be reached by whichever of the three pistons 9a, 9b, and 9C comes first.

For example, if the piston 9C reaches the bottom of the seabed 5 first, the weight of the drilling equipment 40 will be added, so the piston 9C will move upward, so the oil in the upper oil chamber of the hydraulic cylinder 80 will be reduced to the oil in the upper oil chamber of the hydraulic cylinder 8a + 8. The pistons 9a and 9b extend downward.

At that time, the oil in the lower oil chambers of the hydraulic cylinders sa and sb is pushed and moves to the lower oil chamber of the cylinder 8C through the lower communication pipe 12. The piston 9b also landed on the seabed 5, and the hydraulic cylinder 8b,
Since the oil in the upper oil chamber of 8C is sent to the upper oil chamber of the hydraulic cylinder 88, the piston 9a further extends, and when it also reaches the seabed 5, the pressure on the pressure gauge 21 increases.

(4) Mitsutwitch 16a for detecting the position of each piston 79a, 9b, 9c.

The control unit 18 analyzes various conditions such as the signals from the sensors 16b, 16c, 17a, 17b, and 17c, the pressure signal from the pressure gauge 21, and the signal from the inclinometer 15, and then switches the electromagnetic switching valve 14.

Then, the pilot hydraulic pressure is the pilot hydraulic pressure pipe 19. vented through a vent pipe 20;
Each pilot check valve 10a, 10b, 10
c usually functions as a check valve, the communication between the upper oil chambers of each hydraulic cylinder is stopped, and the length of each pillar is fixed.

(5) As a result, each pillar 6a of the test drilling device 4.

6b and 6c are pistons 9a and 9b so as to correctly support the center line of the drilling equipment 4 in the vertical direction even if the seabed 5 is inclined.
, 9c are the respective expanded and contracted lengths, and the center line of the test drilling device 4 is correctly maintained vertically.

In the above embodiment, the following modifications are possible.

(1) It is also possible to eliminate the upper rod part of the piston and use it as a differential cylinder, and to operate the limit switch with the lower rod part of the piston.

(2) Detection of the position of histones is not limited to limit switches, and various means such as a linear transformer can be used.

(3) The solenoid valve can be operated automatically based on information provided to the control unit or remotely from the mothership, which can be freely selected.

In the above embodiment, there are three pillars, but in applying the present invention, the number of pillars is not limited to three.

〔Effect of the invention〕

In short, according to the present invention, in a submarine bottomed structure that lands on the seabed with a plurality of pedestals protruding from the lower end, a plurality of pedestals that extend and contract by hydraulic cylinders and pistons;
A lower communication pipe that communicates the lower hydraulic chambers of each of the hydraulic cylinders with each other, a pilot check valve connected to the upper hydraulic chamber of each of the hydraulic cylinders, and an upper communication pipe that communicates the upstream sides of each of the pilot check valves with each other. By including a pilot hydraulic switching valve that controls each of the pilot check valves mentioned above, a submarine-based structure that can land on the bottom in a vertical position even if the seabed is inclined is obtained. The invention is extremely useful industrially.

[Brief explanation of the drawing]

FIG. 1 is an overall side view showing one embodiment of the present invention, and FIG. 2 is a hydraulic system diagram of the pedestal shown in FIG. 1. DESCRIPTION OF SYMBOLS 1... Mother ship, 2... Crane, 3... Umbilical cable, 4... Seabed-mounted structure, 5... Seabed, 6... Pillar, 7... Trial drilling drill, 8a, 8b. 8C... Hydraulic cylinder, 9a, 9b, 9c... Piston, 10a, 10b, 10C... Pilot check valve, 11... Dobe communication pipe, 12... Lower communication pipe, 13... Accumulator, 14... Solenoid switching valve, 15... Inclinometer, 16a. 1, 6 b, 16 c...Upper limit switch, 17a, 17b, 17c...Lower limit switch, 18...Control unit, 19...Pilot hydraulic pipe, 2
0 ・Vent pipe, 21...Pressure gauge. Sub-Agent Patent Attorney Masa Tsukamoto Figure 1 Figure 2

Claims (1)

[Claims] In a submarine bottomed structure that is attached to the seabed by a plurality of pedestals protruding from the lower end, a plurality of pedestals extend and contract by hydraulic cylinders and pistons, and a lower hydraulic pressure of each of the hydraulic cylinders. a lower communication pipe that communicates the chambers with each other;
A pilot check valve connected to an upper hydraulic chamber of each of the hydraulic cylinders, an upper communication pipe that communicates the upstream sides of each of the pilot check valves with each other, and a pilot hydraulic switching valve that controls each of the pilot check valves. A submarine-based structure characterized by: