JPH08135380A - Screw conveyer - Google Patents

Abstract

PURPOSE: To provide a screw conveyer which can solve the problem of the maintenance as to the abrasion of a flight and a casing, and is suitable for a long distance excavation. CONSTITUTION: In a screw conveyer in which a spiral flight (scraper) 4 is housed in a cylindrical casing 2, and a sediment is conveyed by rotating the flight 4, a sliding member 5 having an antiabrasive property is provided demountable on the outer periphery of a random one pitch of the flight 4. And at the part surrounding the flight 4 of the one pitch, a flight cover 7 with the inner diameter same as the casing 2, and forming a clearance C between the flight 4 of the other pitch and the casing 2, by sliding holding the sliding member 5, is provided allowable to mount and demount.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screw conveyor used for waste disposal of shield excavators and the like.

[0002]

2. Description of the Related Art As shown in FIG. 7, a shield machine a
The (earth pressure type) is provided with a screw conveyor d in order to convey the excavated earth and sand excavated by the cutter b and taken into the cutter chamber c into the mine. Screw conveyor d
Is for accommodating a spiral flight f in a cylindrical casing e and rotating the flight f by a motor g to convey earth and sand.

A predetermined gap is formed between the outer peripheral portion of the flight f and the inner peripheral surface of the casing e in order to ensure smooth rotation of the flight f. Conventionally, such a gap has been formed uniformly over the entire pitch of the flight f. Therefore, the screw conveyor d during the earth and sand conveyance
The outer peripheral portion of all the pitches of the rotating flight f slidably contacts the inner peripheral surface of the casing e.

[0004]

However, when such a screw conveyor d is used for long-distance excavation, the outer peripheral portion of the rotating flight f abrades the inner peripheral surface of the casing e, causing a hole in the casing e. There is. Since the outer peripheral portions of all the pitches of the flight f are in sliding contact with the inner peripheral surface of the casing e evenly, it is not known where the holes are located in the casing e. Therefore, it was necessary to perform patch processing every time a hole was formed, and if the number of holes was large, the entire screw conveyor had to be replaced.

Further, since the wear occurs evenly on the flight f side over the entire pitch, the diameter of the flight f becomes small as shown in FIG. Then, not only the soil discharging ability is reduced, but also the rotation resistance is reduced, so that the rotation speed is increased and the wear is further advanced. In addition, flight f and casing e
Since the gap between the and, will be widened, the effect of soil plug and water blocking will be greatly reduced. Thus, the conventional screw conveyor d cannot be said to be suitable for long-distance excavation, and some improvement has been required.

An object of the present invention, which was devised in view of the above circumstances, is to provide a screw conveyor suitable for long-distance excavation, which can solve the maintenance problem related to the wear of the flight and the casing.

[0007]

In order to achieve the above object, the present invention provides a wear-resistant sliding contact portion which is detachably provided on the outer periphery of an arbitrary pitch of a flight, and which corresponds to that pitch. A portion surrounding the flight is detachably provided with a flight cover that has the same inner diameter as the casing and that slidably supports the sliding contact portion to form a gap between the flight of another pitch and the casing. ing.

Further, the flight cover may be formed so as to be divided into two in the circumferential direction, and a hard portion for substantially slidingly supporting the sliding contact portion may be provided on the inner peripheral surface of the lower cover thereof.

[0009]

The sliding contact portion provided on the outer periphery of any one pitch of the flight is slidably supported by the flight cover surrounding the outer periphery, and a gap is formed between the other pitch of the flight and the casing. . Therefore, the sliding contact wear is limited to the sliding contact portion and the flight cover, and the other parts do not wear. When the sliding contact part and the flight cover have worn to the limit, they are detachable, so replace them with new ones.

The sliding contact portion of the flight is supported mainly by the lower portion of the flight cover by the action of gravity. Therefore, if the flight cover is formed to be bisectable in the circumferential direction and a hard portion is provided on the inner peripheral surface of the lower cover, the sliding contact portion of the flight is substantially slidably supported by the hard portion. Therefore, the durability of the flight cover is improved. When the hard part is worn to the limit, only the lower cover needs to be replaced.

[0011]

An embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows an outline of a screw conveyor 1 used for an earth pressure shield machine. The screw conveyor 1 has a rotating shaft 3 arranged in a cylindrical casing 2 along the longitudinal direction thereof, and a flight 4 spirally attached to the rotating shaft 3 along the axial direction, The rotary shaft 3 is rotated by a motor (not shown) to rotate the flight 4 to convey the earth and sand (FIG. 7).
reference).

A sliding contact portion 5 (carbon steel, super wear resistant alloy, etc.) having wear resistance is detachably provided on the outer periphery of the flight 4 at an arbitrary pitch. The arbitrary one-pitch position where the sliding contact portion 5 is attached is preferably a position apart from the motor g shown in FIG. 7. This is because the flight 4 and the rotating shaft 3 are supported by the motor in a cantilever manner, so that the sliding contact load becomes the largest on the free end side thereof and wear progresses. However, a hard overlay is applied to the inner surface of the casing 2 on the free end side,
There is also a screw conveyor that uses this as a bearing. In this case, since both ends are supported, it is advisable to provide the sliding contact portion 5 at a substantially intermediate position between the motor and the free end.

The sliding contact portion 5 is formed in a U-shaped cross section so as to sandwich the outer peripheral edge of the flight 4, and is attached and detached by a bolt 6. As described above, the outer diameter A of the portion to which the sliding contact portion 5 is attached is larger than the outer diameter B of the portion of the flight of another pitch by the thickness of the sliding contact portion 5. As shown in FIG. 3, the sliding contact portion 5 is formed in a spiral ring shape over the entire circumference of the outer peripheral edge for one pitch of the flight, and is divided at the time of attachment / detachment.
This is to enhance the detachability at the time of replacement. The sliding contact part 5
Is not limited to the bolt 6 and may be removed as a welding stop by cutting the welded portion. Alternatively, it is not limited to the spiral ring shape and may be provided at the outer peripheral edge of the flight 4 at appropriate intervals with a gap. Good.

The casing 2 of the portion surrounding the flight 4 for one pitch to which the sliding contact portion 5 is attached in this manner
Is removed, and a flight cover 7 is detachably provided therein instead. The flight cover 7 slidably supports the sliding contact portion 6 and forms a gap C between the flight 4 having another pitch and the casing 2. The flight cover 7 has flanges 8 at both ends in the axial direction,
These are joined to the flange 9 on the casing 2 side and are joined by bolts 10. Also, the flight cover 7
As shown in FIG. 2, it is formed so that it can be divided into upper and lower parts.
A flange 11 is also provided at the joint between the upper cover 7a and the lower cover 7b, and these are joined by bolts (not shown).

A hard portion 12 is provided on the inner peripheral surface of the lower cover 7b to substantially support the sliding contact portion 5 in sliding contact. That is, the flight 4 is in contact with the lower cover 7b due to its own weight and a slight gap is formed between the flight 4 and the upper cover 7a, so that the flight 4 is substantially slidably supported by the hard portion 12. The hard portion 12 is formed by overlay welding on the inner peripheral surface of the lower cover 7b. As shown in FIG. 3, a plurality of hard facings (hard portions 12) are provided in a line along the axial direction at predetermined intervals in the circumferential direction of the lower cover 7b. This is because the sliding contact area of the sliding contact portion 5 is reduced and the resistance thereof is reduced. The hard facing (hard portion 12) may be applied in layers not on the streaks but on the entire inner surface of the lower cover 7b. In particular, when the sliding contact portions 5 are provided in a scattered manner, the hard facing (hard portion 12) needs to be layered.

The operation of this embodiment having the above configuration will be described.

The sliding contact portion 5 provided on the outer periphery of an arbitrary pitch of the flight 4 is slidably supported by the flight cover 7 surrounding the outer periphery thereof, and between the other pitch of the flight 4 and the casing 2. A gap C is formed. Therefore, the sliding contact wear is limited to the sliding contact portion 5 and the flight cover 7, and no wear occurs in other parts. Therefore, the casing 2 in the portion surrounding the other pitch of the flight 4 is not punctured due to wear, and the patchwork that has been conventionally used for long-distance excavation becomes unnecessary, which shortens the construction period and reduces the construction cost. Can be promoted. Further, when the casing 2 has a hole, the earth pressure of the face is applied to the earth and sand inside, so that the earth and sand is ejected from the hole, but in the present embodiment, this can be prevented, so that the safety is improved.

When the sliding contact portion 5 and the flight cover 7 are worn to the limit, they are detachable and are replaced with new ones. Specifically, as shown in FIG. 2, the lower cover 7 of the flight cover 7 that can be divided into upper and lower halves.
Remove only b, and if the hard part 12 of the lower cover 7b is worn to the limit, replace it with a new one, and
If the sliding contact portion 5 attached to the internal flight 4 is worn to the limit, replace it with a new one. The upper cover 7a does not need to be replaced. Since the flight 4 is mainly supported by the lower cover 7b by the action of gravity,
This is because there is almost no sliding contact with the upper cover 7a.

Since it is not necessary to remove the upper cover 7a when replacing the sliding contact portion 5 and the lower cover 7b, the casings 2 before and after sandwiching the cover 7 are connected via the upper cover 7a and are not displaced. Therefore, workability is improved. It should be noted that the flight cover 7 may be formed in a cylindrical shape of an integral body instead of being divided into upper and lower halves, and may be rotatable about its central axis. In this case, the hard portion 12 is provided on the entire inner surface of the flight cover 7. Then, when the hard portion 12 on the lower side of the cover is worn, the flight cover 7 is turned upside down by rotating 180 degrees so that the hard portion 12 on the upper side of the cover which is not slidably contacted is moved to the lower side.

A modified embodiment is shown in FIGS. 4 and 5. FIG.
In the case shown in (1), the sliding contact portion 5a is not a U-shaped cross section but simply a plate shape. The plate-shaped sliding contact portion 5a is attached to the front side of the flight 4 in the earth and sand transfer direction D by a bolt 13. Moreover, what is shown in FIG. 5 is an example in which the present invention is applied to a so-called ribbon type screw conveyor 1a having no rotating shaft 3. Even in this case, the sliding contact portion 5 is detachably provided on the outer periphery of any one pitch of the ribbon type flight 4a as in the previous embodiment, and the portion surrounding the flight 4a for one pitch is described above. A flight cover 7 that slidably supports the sliding contact portion 5 and forms a gap between the flight 4a of another pitch and the casing 2 is detachably provided.

[0022]

As described above, according to the present invention, since the worn portion of the screw conveyor can be specified to any one pitch, it is sufficient to pay attention to the wear of only the sliding contact portion and the flight cover. Maintainability after long-term use is greatly improved.

[Brief description of drawings]

FIG. 1 is a side sectional view of a screw conveyor showing an embodiment of the present invention.

FIG. 2 is a side view of the screw conveyor with a lower flight cover removed.

3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a diagram showing a modified example.

FIG. 5 is a diagram showing another modified example.

FIG. 6 is a cross-sectional view of the screw conveyor with worn flights.

FIG. 7 is a schematic view of a shield machine equipped with a screw conveyor.

[Explanation of symbols]

 1 Screw Conveyor 2 Casing 4 Flight 5 Sliding Contact 7 Flight Cover 7a Upper Cover 7b Lower Cover 12 Hard Part C Gap

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akira Usami 1-7-1 Kyobashi, Chuo-ku, Tokyo Toda Construction Co., Ltd., Tokyo Branch, Civil Engineering Department (72) Inventor Yuzo Maruyama Koraku, Bunkyo-ku, Tokyo 2- 2-8 Goyo Construction Co., Ltd., Tokyo Branch, Civil Engineering Division (72) Inventor Shinji Sakayo Koraku, Bunkyo-ku, Tokyo 2-2-8 Goyo Construction Co., Ltd., Tokyo Branch, Civil Engineering Division (72) Inventor Yoshida Yuichi Ishii, 11-1 Kitahamacho, Kitahama-cho, Chita-shi, Aichi (72) Inventor Shigekazu Ishii 11-1 Kitahamacho, Chita-shi, Aichi Ishikawajima-Harima Heavy Industry Co., Ltd.

Claims (2)

[Claims] 1. A screw conveyor in which a spiral flight is accommodated in a cylindrical casing, and the flight is rotated to convey earth and sand, and abrasion resistance is provided around an arbitrary one pitch of the flight. Having a sliding property is detachably provided, and a portion surrounding the flight for one pitch has the same inner diameter as the casing, and the sliding contact part is slidably supported to support the flight and the casing of another pitch. A screw conveyor characterized in that a flight cover that forms a gap between the two is detachably provided. 2. The flight cover is formed so that it can be divided into two in the circumferential direction, and a hard portion for substantially slidingly supporting the sliding contact portion is provided on the inner peripheral surface of the lower cover. The screw conveyor according to claim 1.