JPS6056874B2 - Shield tunneling machine face water pressure control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a face water pressure control device for a shield tunneling machine.

Conventionally, in this type of shield excavator, when the water pressure in the face water pressure chamber fluctuates, the valves of the water pipe and mud removal pipe are adjusted to maintain the face water pressure at a set pressure.

However, since the water in the water pipe is generally pumped by a pump, the water pressure in the water pipe is high. Therefore, when the face water pressure fluctuates, especially when the face water pressure decreases, the water pressure at the water pipe must be adjusted to the set pressure. When the opening of the water pipe valve is increased in order to return the water to normal, the water pressure at the water pipe increases rapidly and significantly exceeds the set pressure.As a result, the valve opens and closes repeatedly, causing the water pressure at the water pipe to fluctuate up and down. The drawback was that it took time for the pressure to settle to the set pressure. Such a time delay is
This will have a negative impact on construction management. It is an object of the present invention to provide a control device for the face water pressure of a shield excavator that eliminates the above-mentioned conventional drawbacks and can quickly respond to fluctuations in the face water pressure.

To achieve the above-mentioned objects, the present invention includes a face hydraulic chamber at the front end formed by a partition wall, a water pipe that supplies water to the face hydraulic chamber, and a water pipe that discharges muddy water from the face hydraulic chamber. A water pressure control device for a face water pressure of a shield excavator, which includes a first water supply valve in a water supply pipe portion near the bulkhead, and a bypass pipe having a smaller diameter than the water supply pipe that bypasses the first water supply valve; A second water supply valve is provided close to the upstream side of the bypass pipe, a bypass valve is provided in the bypass pipe, a mud removal valve is provided in a mud removal pipe portion near the partition wall, and the pressure of the face water pressure chamber is detected in the partition wall. a first water pressure transmitter that detects the water supply pressure and outputs a pressure signal, and a second water pressure transmitter that detects the water supply pressure and outputs a pressure signal in the water pipe section between the bypass pipe and the second water supply valve, A predetermined face water pressure value is set, a pressure signal from the first water pressure transmitter is input, and the first water pressure indicating controller outputs a signal according to the deviation from this pressure signal and the set face water pressure value. A first water supply valve, a bypass valve, and a sludge drainage valve each connected to a transmitter and inputting an output signal of the first water pressure indicating controller to adjust the valve opening are connected to the first water pressure indicating controller, A predetermined water supply pressure value that is somewhat higher than the set pressure of the first water pressure indicating controller is set, and the pressure signal of the second water pressure transmitter is input, and the deviation between this pressure signal and the set water supply pressure value is determined. A second water pressure indicating controller that outputs a signal is connected to the second water pressure transmitter, and the output signal of the second water pressure indicating controller is input, and the second water supply valve that adjusts the valve opening is connected to the second water pressure transmitter. It is characterized by being connected to a controller. An embodiment shown in the drawings will be described below.

A face hydraulic chamber 4 is formed by a partition wall 2 at the front end of the shield tunneling machine 1, and a water pipe 6 equipped with a water pump P1 and a sludge drain pipe 1 equipped with a sludge pump P2 are formed in the face hydraulic chamber 4.
One end of each of the pipes 6 and 11 is open, and the other ends of each of the pipes 6 and 11 are opened to a water tank 10 installed on the ground. 3 is a cutter, and 20 is a segment.

In the part of the water pipe 6 near the partition wall 2, there is a first water valve 9, a bypass pipe 7 that bypasses it, and a second water pipe 7 that is close to the upstream side of the first water valve 9.
A water supply valve 17 is provided respectively.

The bypass pipe 7 is provided with a bypass valve 8, and the diameter of the bypass pipe 7 is significantly smaller than that of the water pipe 6. A sludge valve 13 is provided in the sludge pipe 11 portion near the partition wall 2, and one end of a connecting pipe 14 is provided with a valve 19 in the sludge pipe 11 portion between the sludge valve 13 and the sludge pump P2. is connected, and the other end is connected to the water pipe 6 between the first and second water valves 9 and 17.
connected to the parts.

The bulkhead 2 is provided with a first water pressure transmitter 5 that detects the pressure in the face water pressure chamber 4 and outputs a pressure signal, and this first water pressure transmitter 5 is connected to a first water pressure indicating controller 12 by a signal line. , this first water pressure indicating regulator is connected to the bypass valve 8, the first water supply valve 9, and the sludge drainage valve 13 through signal lines, respectively. When a predetermined face water pressure value is set and a pressure signal from the first water pressure transmitter 5 is input, the first water pressure indicating controller 12 outputs a signal according to the deviation between this pressure signal and the set face water pressure value. However, this output signal is inputted to the bypass valve 8, or the first water supply valve 9, and the sludge removal valve 13, and the opening degrees of these valves are adjusted. 18 is a switch for a signal line to the first water supply valve 9 and the sludge drainage valve 13.

A second water pressure transmitter 15 is provided in a portion of the water supply pipe 6 between the bypass pipe 7 and the second water supply valve 17, and this second water pressure transmitter 15 is connected to a second water pressure indicating controller 16 by a signal line. This second water pressure indicating controller 16 is connected to a second water supply valve 17 by a signal line.

The second water pressure indicating controller 16 sets a predetermined water supply pressure value (setting face water pressure value + 0.2 to 0.0.
4k91a1) is set and a pressure signal from the second water pressure transmitter 15 is input, a signal corresponding to the deviation between this pressure signal and the set water supply pressure value is output, and this output signal is
The water is inputted to the water supply valve 17, and the valve opening degree is adjusted. That is, the water supply pressure within the water supply pipe 6 on the upstream side of the bypass valve 8 and the first water supply valve 9 is always maintained at a pressure value that is somewhat higher than the set face water pressure value. Next, the operation of the above will be explained.

(4) When excavation is stopped When excavation is stopped, the water pressure in the face hydraulic chamber 4 is relatively stable, and the hydrostatic pressure of the water tank 10 alone can counteract the pressure of the ground.

That is, the water supply pump P1 and the sludge pump P2 are stopped, and the first water supply valve 9, the sludge drainage valve 13, and the valve 19 of the connecting pipe 14 are stopped.
is closed, and only the opening degrees of the bypass valve 8 and the second water supply valve 17 are adjusted. When the excavation is stopped, the water pressure at the face almost never increases, and if the water pressure at the face falls below the set pressure due to water loss to the ground, although it is small, the first water pressure transmitter 5 detects this pressure. , the first water pressure indicating controller 12 sends a signal corresponding to the deviation between the pressure signal and the set face water pressure to the bypass valve 8, increases its opening degree, and raises the face water pressure to the set pressure.

In this way, through the bypass pipe 7, which has a smaller diameter than the water pipe 6,
Furthermore, by supplying water at a pressure somewhat higher than the set face water pressure value to the face water pressure chamber 4, a phenomenon in which the water pressure in the face water pressure chamber 4 suddenly increases and exceeds the set pressure does not occur. Can quickly respond to minute fluctuations in face water pressure.

(B) During excavation In preparation for excavation, close the bypass valve 8 and
The valve 19 of the connecting pipe 14 is opened, and the water pump P1 and the sludge pump P2 are started to operate.

That is, without supplying water to the face water pressure chamber 4, the water pipe 6,
Water is circulated through the pipe line formed by the connecting pipe 14 and the mud removal pipe 11, and the water supply pressure in the water supply pipe 6 upstream of the first water supply valve 9 is maintained at a set pressure by adjusting the opening degree of the second water supply valve 17. .
The reason for performing such an operation is that if water is suddenly supplied to the face water pressure chamber 4 by the water supply pump P1, the face water pressure will fluctuate greatly. From the above state, the first water supply valve 9 and the sludge removal valve 13 are opened, and the switch 18 is closed to adjust the opening degrees of both valves 9 and 13. At the same time, the valve 19 of the connecting pipe 14 is closed and the face is closed. Water is supplied to the water pressure chamber 4, and excavation work is started.

If the water pressure at the face rises above the set pressure during excavation, the first water pressure transmitter 5 transmits the pressure. Detected, the first water pressure indicating controller 12 sends a signal according to the deviation between the pressure signal and the set face water pressure to the first water supply valve 9 and the mud removal valve 13, and reduces the opening degree of the first water supply valve 9. , the opening degree of the mud removal valve 13 is increased, and the face water pressure is lowered to the set pressure. When the water pressure at the face falls below the set pressure, contrary to the above, the first water pressure indicating controller 12 increases the opening degree of the first water supply valve 9 according to the deviation between the pressure signal and the set water pressure at the face. , the opening degree of the sludge valve 13 is decreased, and the face water pressure is increased to the set pressure.

At this time, the pressure of the water supplied to the face water pressure chamber 4 is somewhat higher than the set face water pressure value, and therefore it is not high pressure water as in the past, so the face water pressure increases rapidly. The set pressure is quickly reached without fluctuating up and down significantly above the set pressure. When the face water pressure fluctuates as described above, the opening degree of the first water supply valve 9 is adjusted, so the pressure inside the water supply pipe 6 on the upstream side fluctuates.
The second water pressure transmitter 15 detects this, and the second water pressure indicating controller 16 adjusts the opening of the second water supply valve 17, so that the water supply pressure is always maintained at a predetermined pressure.

As described above, according to the present invention, the water supply pressure in the water pipe on the upstream side of the first water supply valve is always maintained at a water pressure value somewhat higher than the set face water pressure value by adjusting the valve opening degree of the second water supply valve. is,
When the water pressure at the face falls, water with this predetermined pressure is supplied to the face water pressure chamber, so that the set pressure can be quickly reached without any time delay, and good construction management can be performed.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional front view showing an embodiment of the present invention. 1... Shield tunneling machine, 2... Bulkhead,
4...Face hydraulic chamber, 5...First water pressure transmitter, 6...Water pipe, 7II●●●●bypass pipe, 800●●◆●bypass valve, 9$$●...First water supply valve, 11...Sludge removal pipe, 12...First
Water pressure indicator controller, 13...Sludge valve, 13...
...Second water pressure transmitter, 16...Second water pressure indicating controller, 17...Second water supply valve.

Claims (1)

[Claims] 1. Face water pressure of a shield excavator equipped with a face water pressure chamber at the front end formed by a bulkhead, a water pipe that supplies water to this face water pressure room, and a mud removal pipe that discharges muddy water from the face water pressure room. In the control device, a first water supply valve is provided in a water supply pipe portion near the partition wall, a bypass pipe having a smaller diameter than the water supply pipe that bypasses the first water supply valve, and a second water supply valve that is close to the upstream side of the bypass pipe. A bypass valve is provided in the bypass pipe, a sludge removal valve is provided in the sludge removal pipe portion near the bulkhead, and a first water pressure transmitter is provided on the partition wall for detecting the pressure in the face water pressure chamber and outputting a pressure signal. In addition, a second water pressure transmitter is provided in the water pipe portion between the bypass pipe and the second water supply valve to detect the water supply pressure and output a pressure signal, and a predetermined face water pressure value is set.
A first water pressure indicating controller that inputs the pressure signal of the first water pressure transmitter and outputs a signal according to the deviation between this pressure signal and the set face water pressure value is connected to the first water pressure transmitter, and the first water pressure The first water supply valve, bypass valve, and sludge drainage valve, each of which inputs the output signal of the indicating controller and adjusts the valve opening, are connected to the first water pressure indicating controller, and the set pressure of the first water pressure indicating controller is adjusted. A second water pressure instruction which inputs a pressure signal from a second water pressure transmitter and outputs a signal according to the deviation between this pressure signal and the set water pressure value. The controller is connected to a second water pressure transmitter, and the output signal of the second water pressure indicating controller is inputted to adjust the valve opening degree.The second water supply valve is connected to the second water pressure indicating controller. A control device for water pressure at the face of a shield tunneling machine.