JPS6115234B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mud water transport device for a mud water pressurized shield tunnel excavation device, and in particular to a mud water transport device for supplying pressurized mud water from a mud feeding pipe to a mud removal pipe without passing through a mud water pressurizing chamber. Concerning jet pumps for promoting mud.

As the tunnel is excavated, the route for transporting and discharging mud becomes longer, and in addition to the mud pump and mud removal pump installed near the tunnel entrance, intermediate pumps for mud removal are usually installed at intervals of about 70 m. Ru. If the diameter of the tunnel is large, the necessary space for installing an intermediate pump can be secured within the tunnel, but in the case of a small diameter tunnel, for example, 600 to 900 mm, there is not enough room to install an intermediate pump. . For this reason, intermediate pumps installed in tunnels must be extremely compact.

The present invention aims to downsize the intermediate pump, but instead of providing an independent suction pump, pressurized mud water is introduced into the mud removal pipe through the mud feeding pipe to increase the mud removal pressure. The basic concept is to facilitate the discharge of muddy water, that is, mixed muddy water. Such a pump is called a jet pump, but the present invention is designed to smoothly discharge muddy water flowing through the mud draining pipe without interfering with the flow of muddy water, especially muddy water mixed with gravel. It is characterized in that the pressurized mud water injection part does not protrude into the mud removal pipe, so that the injection part does not interfere with the flow of gravel in the mud removal pipe.

The jet pump according to the present invention includes a pressurized mud water intake section provided on a mud feeding pipe, a pressurized mud water supply section provided on a mud removal pipe, and a conduit connecting the intake section and the supply section. a casing having an end wall substantially perpendicular to the axis of the sludge pipe; a sludge pipe enlarged diameter portion that extends to the sludge pipe in the direction of sludge removal through the end wall; It consists of a plurality of pressurized mud water injection holes provided. The pressurized mud water is led from the intake section through the conduit into the casing of the supply section, and further passes through the injection hole provided at the end of the casing into the mud removal pipe, that is, the expanded diameter constituting the mud removal pipe. It pressurizes the mixed mud water that flows through the mud drainage pipe and promotes its flow.

The features of the present invention will become clearer from the following description of the illustrated embodiments.

As shown in FIG. 1, the jet pump 10 according to the present invention pumps mud from a sedimentation tank 12 installed on the ground through a pump 14, a shaft 16, and a tunnel 18 to a bulkhead 21a of a pressurized mud shield excavation device 20 and the front thereof. The mud feeding pipe 24 that sends pressurized mud to the mud water pressurizing chamber 22 defined between the cutter head 21b and the mud water pressurizing chamber 22 has a pressurized mud water intake section 26.
A pressurized slurry supply section 32 is provided in the slurry drain pipe 30 that extends from the mud pump 28 installed in the shaft 16 to the sedimentation tank 12, and further connects the intake section 26 and the supply section 32 to supply water from the former. It has a conduit 34 for guiding pressurized mud into the latter. The mud feeding pipe 24 is provided with a pressure regulating valve 36 and a water feeding valve 38, and the mud draining pipe 30 is provided with a mud draining valve 40.
4 and 30 are a bypass pipe 42 and a bypass valve 44
is provided.

As shown in FIG. 2, the pressurized mud water intake section 26
includes a plurality of pressurized mud water spouting holes 46 provided around the mud feeding pipe 24 and penetrating the pipe wall. Since the pressurized mud water is precipitated in the sedimentation tank 12, the pressurized mud does not contain the 〓, but it is preferable to provide a filter (not shown) in the spout hole 46. The intake section 26 also includes a casing 50 that surrounds the slurry pipe 24 and covers and surrounds all the spout holes 46, forming a pressurized mud chamber 48 therein. Casing 5
0 is connected to a conduit 34.

As is clear from FIG. 2 and FIG.
The casing 54 surrounds the outer periphery of the equal diameter portion 30a of 0 and forms a pressurized mud water chamber 52 inside, and the casing is a casing portion provided on the outer periphery of the end of the equal diameter portion 30a of the mud removal pipe, that is, an end wall. 56. The end wall 56 is substantially perpendicular to the axis of the mud removal pipe, and has a plurality of spaced pressurized mud water injection holes 58 throughout the end wall.

An enlarged diameter portion 30b extending in the direction of mud removal is connected to the equal diameter portion 30a of the mud removal pipe via an end wall 56. The enlarged diameter portion 30b of the mud removal pipe has a tapered shape as a whole, and has a maximum diameter near the end wall 56,
The diameter gradually decreases in the sludge removal direction shown by the arrow, and returns to the continuous equal diameter portion 30a.

Since the enlarged diameter portion 30b is tapered and the pressurized mud water is injected through the end wall 56 in its maximum diameter region,
High-pressure water can be introduced into the mud removal pipe 30 without substantially reducing the diameter, that is, the inner diameter of the mud removal pipe,
The flow of the gravel 60 mixed in the drained mud water is not obstructed, and since the expanded diameter portion 30b has a tapered shape that gradually reduces the diameter, gravel and earth and sand do not stagnate within the expanded diameter portion, allowing smooth drainage. Mud is promoted.

During operation of the mud water transport system, a portion of the pressurized mud water in the mud feed pipe 24 flows from the spout hole 46 of the intake section 26 to the pressurized mud chamber 48, the conduit 34, and the pressurized mud chamber 52 of the supply section 38, and then flows to the end. Sludge drainage pipe 30 from the injection hole 58 of the wall 56
As described above, the fluid continues to be injected into the enlarged diameter portion 30b of the fluid, and as described above, the fluid continues to be pressurized and encouraged to flow without hindering the flow of the fluid.

In the illustrated example, one jet pump 10 is provided, but as the tunnel is excavated, this jet pump can be installed near the tunnel entrance at regular intervals, making it difficult for workers to enter and creating an independent suction pump. It is possible to advantageously promote the transportation of muddy water using a small-diameter shield that cannot be installed due to space and efficiency considerations.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing a mud water transport system for a mud water pressurized shield excavation device equipped with a jet pump according to the present invention, Fig. 2 is a longitudinal sectional view of the jet pump, and Fig. 3 is a line 3-- FIG. 10...Jet pump, 24...Sludge feeding pipe, 26...
Pressurized mud water intake part, 30... Sludge removal pipe, 30a... Equal diameter part, 30b... Expanded diameter part, 32... Pressurized mud water supply part, 3
4... Conduit, 50, 54... Casing, 56... Casing portion (end wall), 58... Pressurized mud water injection hole.

Claims (1)

[Scope of Claims] 1. A pressurized mud water intake section provided in a mud feeding pipe extending from earth equipment to a mud water pressurizing chamber of a mud water pressurizing type shield tunnel excavation device, and a pressurized mud water intake part provided in a mud feeding pipe extending from the earth equipment to the mud water pressurizing chamber of the mud water pressurizing type shield tunnel excavation device; a pressurized mud water supply section provided in the sludge drainage pipe extending to the sludge drainage pipe; and a conduit connecting the pressurized mud water intake section and the pressurized mud water supply section, the pressurized mud water supply section being connected to the sludge drainage pipe. a casing that surrounds the sludge removal pipe and has an end wall substantially perpendicular to the axis of the sludge removal pipe; and a sludge removal pipe enlarged diameter portion that connects to the sludge removal pipe in the sludge removal direction via the end wall; A jet pump for transporting muddy water, comprising a plurality of pressurized muddy water injection holes provided in the end wall. 2. The jet pump according to claim 1, wherein the enlarged diameter portion of the mud removal pipe has a maximum diameter near the end wall and has a tapered shape that gradually decreases in diameter in the mud removal direction. 3 The pressurized mud water intake section includes a plurality of pressurized mud water spout holes provided around the mud feeding pipe, a filter provided in the pressurized mud water spout holes, and a filter surrounding the mud feeding pipe and the pressurized mud water injection hole. A jet pump according to claim 1, comprising a casing that covers a pressurized mud water jet hole.