JP4223371B2 - Continuous decontamination equipment for small-diameter piping - Google Patents

Description

  The present invention relates to an apparatus for decontaminating a long small-diameter pipe generated as a waste at a nuclear power plant. More specifically, it is a device that decontaminates condenser water chamber cooling pipes to be removed and the surface of small-diameter small-diameter pipes that have been produced in large quantities due to decommissioning. The present invention relates to a continuous decontamination apparatus for small-diameter pipes that performs decontamination by wiping or polishing with a nylon scrubber.

  Conventionally, in order to decontaminate a long, small-diameter pipe generated at a nuclear power plant, the waste was wiped manually using one waste at a time, but this was very inefficient due to the time and number of people. . In this way, if it is carried out manually, unwiping and decontamination unevenness occur, and it is necessary to sufficiently check by a contamination inspection. Furthermore, since it can be wiped off only on one side of the waste, waste of waste is large, and the amount of waste is also large, and improvement of this operation has been desired.

  In a nuclear power plant or the like, a method of exposing a gas such as ozone, oxygen, or an organic fluorine compound to decontamination of a facility, equipment, piping, etc. contaminated with a radioactive substance is performed (see Patent Document 1). However, there is no automatic decontamination for decontamination of small-diameter pipes.

  The decontamination of long-sized small-diameter piping of nuclear power generation facilities is as described above, but in general industries, in a car, a printing machine, a magnetic card and a coin washing device, a belt conveyor is used as a feeding device. A cleaning device using a waste cloth as a wiping device is known.

  For example, a prepaid card cleaning device is known in which a card is placed on a conveyor belt and cleaned and wiped with a pressure roll (see Patent Document 2).

  As a workpiece surface cleaning device, there is also known a workpiece surface cleaning device including a moving means for moving a workpiece, a waste fed from a feeding reel, and a pressing means for pressing the waste against the workpiece surface. (See Patent Document 3).

As described above, in decontamination other than waste, chemicals are used for chemical decontamination, and abrasives are used for physical decontamination. Therefore, a large-scale decontamination facility is required and a lot of waste is generated.
Japanese Patent Application No. 2000-403579 Japanese Patent Application No. 4-359131 Japanese Patent Application No. 9-2478

  The conventional waste system is decontaminated for the decontamination of small-diameter pipes, and this is intended to enable efficient work with a simple device. That is, by rotating the upper and lower belt conveyors and passing the small-diameter pipe between the upper and lower belt conveyors, the small-diameter pipe is slowly moved while rotating at high speed. And while small-diameter piping passes a belt conveyor, it intends to provide the apparatus which decontaminates continuously using a nylon scrubber and a cloth wiping machine, and the whole surface uniformly.

(1) A continuous decontamination device for small-diameter pipes includes a main body frame, a pair of upper conveyor belts wound around sprockets provided at the front and rear of the main body frame, and spaced apart on both sides in the rolling direction of the small-diameter pipe. A lower conveyor belt disposed in parallel to the lower portions of the pair of upper conveyor belts, driven in the same direction as the upper conveyor belt, and driven at a higher speed than the upper conveyor belt, and the upper conveyor belt and the lower A pipe feeding mechanism that feeds small-diameter pipes between conveyor belts, and a waste cloth that wipes the surface of small-diameter pipes while slowly feeding the small-diameter pipes that are fed back in the feed direction while rotating backward due to the speed difference between the upper and lower conveyor belts. It consists of a wiping device.
(2) The pipe feed mechanism comprises a cam that is rotated manually or electrically, and the small-diameter pipe fed from the cam in a state orthogonal to the upper and lower conveyor belts automatically passes through a pipe feed guide having a downward slope. Sent.
(3) The waste wiping device is provided at the upper part of the main body frame, can be moved up and down by a wiping machine vertical movement handle provided at the upper part of the waste wiping device, and has a spring for holding a wiping load. Thus, the waste fed from the waste roll in the waste wiping device is wound around the used waste roll via the lower surface of the waste pressing plate provided at the lower end of the waste wiping device.
(4) The main body frame is provided with a nylon scrubbing pressing mechanism having a nylon scrubber on the lower surface in order to cope with a case where the waste wiping device is particularly contaminated.
(5) The main body frame is provided with an upper belt presser for pressing the upper conveyor belt, and the upper belt pressing force by the upper belt pressing spring can be adjusted by turning the pressing force adjusting handle.
(6) The waste cloth wiping device includes a water spray for moistening a small-diameter pipe before wiping.

  Conventionally, in order to decontaminate small-diameter pipes, the waste was wiped manually using one piece of waste at a time, but it was very inefficient due to the time and number of people, but continuous decontamination of small-diameter pipes. By using the apparatus, it was possible to decontaminate in about 1 second, which previously took 20 seconds with a 3 m pipe.

  If it is done manually, wiping residue and decontamination unevenness will occur.Therefore, it was necessary to make a thorough check in the contamination inspection, but the device of the present invention is an automatic machine that uses a uniform pressure to adjust the waste. It can be wiped by pressing against small-diameter piping. In addition, by changing the rotational speed of the upper and lower belt conveyors, the number of wiping operations can be adjusted according to the contamination level. Therefore, if the contamination level is high, the number of wiping operations can be increased and decontamination can be performed according to the contamination state.

  By adjusting the waste feed speed in accordance with the feed speed of the small-diameter pipe, the entire waste is wiped off, so there is no waste of waste and the amount of waste can be reduced.

  In FIG. 1, reference numeral 1 denotes a main body frame. An upper conveyor drive motor 2 and a lower conveyor drive motor 3 are mounted on the main body frame 1. The upper conveyor drive motor 2 drives the upper conveyor belt 4 via the sprocket 6, and the lower conveyor drive motor 3 drives the lower conveyor belt 5 via the sprocket 8.

  As shown in FIG. 2, the upper conveyor belt 4 is wound between the front and rear sprockets 6 and 7 on both sides of the apparatus, and the lower conveyor belt 5 is also wound between the front and rear sprockets 8 and 9. ing.

  Both the upper conveyor belt and the lower conveyor belt are driven in the same direction by the conveyor drive motor 2 (FIG. 4). Accordingly, on the side in contact with the small-diameter pipe (hereinafter referred to as a narrow pipe) 10, the pipes rotate in opposite directions. In other words, the upper conveyor belt 4 is driven in the direction opposite to the direction in which the thin tubes 10 to be decontaminated are driven on the side in contact with the thin tubes 10, and the lower conveyor belt 5 is driven at a higher speed than the upper conveyor drive belt in the direction of sending the thin tubes 10. Driven. As shown in FIG. 2, the conveyor belt is located on both sides of the apparatus in both the upper and lower sides, and is sandwiched between the upper and lower conveyor belts on both sides, and the thin tube 10 is fed while rotating.

  The upper conveyor belt 4 is always given an appropriate pressing force via the upper belt pressing spring 12 (FIG. 3) by turning the upper belt pressing force adjusting handle 11. The lower belt presser 13 is fixed upward at an intermediate position of the main body frame 1.

  As described above, the upper conveyor belt 4 and the lower conveyor belt 5 rotate in opposite directions to each other above the lower belt retainer 13, and downward from the upper portion with the upper belt retainer 14 (details are shown in FIG. 3). It is pressed toward

  On the other hand, the waste wiping device 15 is provided on the upper part of the main body frame 1 so as to be vertically movable with respect to the machine frame 15 ′. The waste wiping device 15 can be moved up and down by manually operating the waste wiping device vertical movement handle 16. Reference numeral 17 denotes a wiping machine load holding spring, which can apply and hold a desired pressing force to the wiping portion. The waste wiper 15 is raised and lowered by being guided by a lifting guide rod 18 fixed on the machine frame side. Reference numeral 19 denotes an elevating linear bush, which is attached to the elevating waste wiping device 15 and is slidable relative to the elevating guide rod 18.

  Reference numeral 20 denotes a new waste roll, and the waste 21 fed from the roll 20 is fed in the direction of the arrow a in FIG. 1 and the waste pressing plate 26 provided at the lower end of the wiper roll 22 and the waste wiper 15. Is wound up through the wiping roll 23 and wound up on the used waste roll 24. The used waste roll 24 is driven by a winding motor 25.

  The waste 21 is wound up from the wiping roll 22 through the lower surface of the waste pressing plate 26 on the upper conveyor belt 4 and wipes the surface of the thin tube 10 that is transferred during this time.

  In FIG. 1, a water spray 27 is provided in the vicinity of the waste roll 22, so that the waste 21 is moistened, and then the surface of the thin tube 10 is wiped off and wound up and collected by the used waste roll 24.

  If the thin tube 10 is very dirty, it is polished using a nylon scrubber 28 attached to the main body frame 1 (before the waste pressing plate 26). The nylon scrubbing mechanism 29 has a nylon scrubber 28 fixed to the flat portion of the lower surface, and the side into which the thin tube 10 enters has an inclined surface so that the thin tube 10 can smoothly enter and contact. The nylon scrubbing mechanism 29 presses the nylon scrubber 28 downward with its own weight or a spring (not shown).

  The thin tube 10 before decontamination is supplied to the pipe feeder 30 and is continuously transferred to the main body frame 1 side by rotating the cam 31 manually or electrically. Since the narrow pipe 10 has a descending slope in the pipe feed guide 32, when it rolls to the conveyor belt, it is sandwiched between the upper and lower conveyor belts 4 and 5 running in the opposite direction, and rotates at a high speed due to the speed difference between the upper and lower conveyor belts. Slowly move to the waste wiper 15 side and pass through the waste wipe surface of the waste wiper 15. At this time, the cloth is wiped with the waste for the number of rotations rotated while passing through the waste wipe width L (FIG. 4). The thin tube 10 after decontamination is continuously sent by a conveyor belt and sent to a container prepared in advance.

About feeding and decontamination of small-diameter piping:
When the upper and lower belt conveyors 4 and 5 are rotated in the same direction, the belts 4 and 5 sandwiching the pipe 10 run in opposite directions as shown in FIG. At this time, since there is a speed difference between the speeds V1 and V2 of the upper conveyor belt and the lower conveyor belt, the pipe 10 to be fed rotates at a high speed, but the pipe moves in the delivery direction at a slow movement speed. For this reason, the surface of the pipe can be cleaned and decontaminated by pressing the waste cloth 21 and the nylon scrubber 28 against the pipe 10 rotating at a high speed.
Moreover, if the rotational speed of the upper and lower conveyors is adjusted according to the degree of contamination of the pipes, the moving speed of the pipes 10 can be increased and the number of wiping operations can be adjusted.

By supplying the thin tube 10 between the upper and lower belt conveyors 4 and 5 with a separately provided piping feeder 30, a large amount of piping can be processed continuously in a short time.
With reference to FIG. 4 and FIG. 5, the decontamination principle of a thin tube performed in the continuous decontamination device of a thin tube is demonstrated.
In Fig. 4 d: Diameter of capillary (m)
D: Conveyor roller diameter (m)
V ₁ : Upper conveyor feed speed (m / sec)
V ₂ : Lower conveyor feed speed (m / sec)
V ₃ : Pipe moving speed (m / sec)
n ₁ : Rotational speed of upper conveyor (r / sec)
n ₂ : Lower conveyor rotation speed (r / sec)
n ₃ : Rotational speed of thin tube (r / sec)
t: tubule wiping time in wiping section (sec)
x: Number of times of thin tube wiping (times)
L: The length of the wiping part (m)
V ₁ = π · D · n ₁
V ₂ = π · D · n ₂
n ₃ = (n ₁ + n ₂ ) · D / 2 · d
_{V 3 = π (n 2 -n} 1) · D / 2 = V 1 -V 2/2
t = L / V ₃
x = n ₃ · t

  With the above operating principle, the thin tube 10 is slowly fed and efficiently decontaminated while rotating at high speed. However, as is apparent from FIG. 2, the single wiper 15 does not clean the thin tube 10 from end to end.

  Therefore, as shown in FIGS. 5 and 6, the waste wiping machine 15 is mounted on the main body frame 1 and decontamination is performed over the entire length of the narrow tube so that the waste passes through the narrow tube 10 from end to end. It can be so.

  With the above-described configuration, the relationship between the thin tube wiping time and the relationship between the number of thin tube wiping times was tested when the rotational speeds of the upper conveyor and the lower conveyor were changed. The results are described below.

  Table 1 shows the decontamination test of a 28.6 mm thin tube. The rotation number (rpm) of the upper conveyor is shown horizontally, the rotation number (rpm) of the lower conveyor is shown vertically, and the position corresponding to each rotation number is shown. The wiping time (sec) is shown. For example, when the upper conveyor is set at 30 rpm and the lower conveyor is set at 60 rpm, the thin tube wiping time is 2.67 sec.

  Table 2 shows the same number of thin tubes of 28.6 mm as in Table 1, and shows the number of times of thin tube wiping (times) when the rotation speed (rpm) of the upper and lower conveyors is changed. For example, when the upper conveyor is 30 rpm and the lower conveyor is 60 rpm, the number of wiping operations is 5.33.

  When Table 1 and Table 2 are considered, the wiping time and the number of times of wiping of the thin tube are within a range that is preferably surrounded by a thick line in the table. That is, the wiping time is preferably 1.60 to 2.67 (sec), and the number of wiping times is preferably about 3.55 to 8.88 times, and it does not take too much time, and too much wiping. It was found that the range other than the number of times is a suitable numerical value.

  Table 3 shows the decontamination test of a 25.4 mm thin tube. The rotation number (rpm) of the upper conveyor is shown horizontally, the rotation number (rpm) of the lower conveyor is shown vertically, and the position corresponding to each rotation number is shown. The wiping time (sec) is shown. For example, when the upper conveyor is set at 30 rpm and the lower conveyor is set at 70 rpm, the thin tube wiping time is 2.26 sec.

  Table 4 shows the same number of thin tubes as 25.4 mm as in Table 3, and shows the number of times of thin tube wiping (times) when the rotation speed (rpm) of the upper and lower conveyors is changed. For example, when the upper conveyor is 30 rpm and the lower conveyor is 70 rpm, the number of wiping operations is 5.06.

  Considering Table 3 and Table 4, the wiping time and the number of times of wiping of the thin tubes are each in a preferable range surrounded by a thick line in the table. In other words, the wiping time is preferably 1.81 to 2.26 (sec), and the number of wiping times is preferably about 3.38 to 6.75 times, and it does not take too much time, and too much wiping. It was found that the range other than the number of times is a suitable numerical value.

  Thus, if the upper and lower conveyors are driven in the same direction and their rotational speeds are different by about 40 rpm, the thin tubes are slowly fed in the discharge direction while rotating at a high speed. The number of times of wiping is given, and the intended decontamination becomes possible.

The side view of a small diameter piping decontamination apparatus. The top view of FIG. Detailed view of the upper conveyor belt pressing device. (A) is detail drawing of the part which decontaminates the thin tube sent with an up-and-down conveyor belt, (b) is a feed state explanatory drawing of the up-and-down belt conveyor. The side view of the Example which attached multiple waste wipers (4 pieces). FIG. 6 is a top view of FIG. 5.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Main body frame 2 Upper conveyor drive motor 3 Lower conveyor drive motor 4 Upper conveyor belt 5 Lower conveyor belt 6 Sprocket 7 Sprocket 8 Sprocket 9 Sprocket 10 Narrow tube
11 Upper belt pressing force adjustment handle 12 Upper belt pressing spring
13 Lower belt retainer 14 Upper belt retainer
15 Waste wiper
15 'Machine frame (of cloth wiper)
16 Vertical movement handle 17 Load holding spring
18 Lifting guide rod 19 Lifting linear bush
20 waste roll 21 waste
22 Wiping roll 23 Wiping roll
24 Used waste roll 25 Winding motor
26 Waste pressure plate 27 Water spray
28 Nylon scrubbing 29 Nylon scrubbing mechanism
30 Pipe feeder 31 Cam
32 Pipe feed guide

Claims (6)

Body frame,
A pair of upper conveyor belts that are wound around sprockets provided at the front and rear of the main body frame and spaced on both sides in the rolling direction of the small-diameter pipe, and arranged in parallel at the lower portions of the pair of upper conveyor belts. A lower conveyor belt driven in the same direction as the upper conveyor belt and driven at a higher speed than the upper conveyor belt;
A pipe feeding mechanism for feeding a small-diameter pipe between the upper conveyor belt and the lower conveyor belt;
A continuous decontamination apparatus for small-bore pipes, comprising a waste wiping device for wiping the surface of the small-bore pipes while slowly rotating the fed small-bore pipes in the feed-out direction while reversely rotating due to the speed difference between the upper and lower conveyor belts. The pipe feed mechanism is a cam that is rotated manually or electrically, and the small-diameter pipe fed from the cam in a state perpendicular to the upper and lower conveyor belts is automatically fed through a pipe feed guide having a downward slope. The continuous decontamination apparatus for small-diameter piping according to claim 1. The waste wiping device is provided at the upper part of the main body frame, can be moved up and down by a wiping handle vertical movement handle provided at the upper part of the waste wiping device, and has a wiping load holding spring. 2. The small cloth according to claim 1, wherein the waste fed from the waste roll in the waste wiper is wound around the used waste roll via the lower surface of the waste pressing plate provided at the lower end of the waste wiper. Continuous decontamination equipment for caliber piping. The continuous decontamination apparatus for small-bore pipes according to claim 1, wherein the main body frame is provided with a nylon scrubber pressing mechanism having a nylon scrubber on the lower surface in order to cope with a particularly severe contamination of the wiping apparatus. The small-bore pipe according to claim 1, wherein the main body frame is provided with an upper belt presser for pressing the upper conveyor belt, and the upper belt pressing force by the upper belt pressing spring can be adjusted by turning a pressing force adjusting handle. Continuous decontamination equipment. The said waste cloth wiping apparatus is a continuous decontamination apparatus of the small diameter piping of Claim 1 provided with the water spray which wets this before wiping of small diameter piping.

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