JPS607987A - Method of washing inner wall of pipe of reducing piping - 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] Kii 11 Akira relates to an improvement of a pipe inner wall cleaning method for 7-use piping using a mixture of an abrasive material and a conveying gas, thereby making the entire inner wall surface of the pipe passage more uniform. The present invention relates to a pipe inner wall cleaning method that enables grinding and cleaning.

The applicant previously developed a method for cleaning the inner wall surface of a regi-use pipe using a mixture of an abrasive and a conveying gas, and published it as Publication No. 57-60071. That is,
As shown in FIG. 1, a mixture 4 of an abrasive material 2 such as crushed sand and a conveying gas 3 such as compressed air is spouted from the open I end of the regi-use piping 1, and Supplying acceleration adjusting gases 8, 9, and 1.0 from the open ends of branch pipes 5 and 6.7 provided at each expanded diameter portion of the piping, respectively;
By sequentially adjusting the supply amount of the acceleration adjustment gas from the small diameter 111 side, each arrangement making up the register use arrangement is
']l, 12.

The basic idea is to adjust the flow rate of the mixture of abrasive material and transport gas flowing through J3 to an optimum value corresponding to the diameter of each pipe 1''. In addition, in Figure 1, ]< is kelp 1
15 is an abrasive material (crushed sand J tank, J6 is a mixing ejector, 17 is an accelerator, and 8 is an abrasive material recovery device.

In method 1 in Figure 1iii, the pipe diameters are sequentially different. The entire inner wall surface of the reuse piping can be uniformly ground (61), but the large diameter piping side may not be sufficiently ground, or the small diameter piping side may be deeply ground, causing damage to the pipe. It has excellent practical utility.

However, there are still many problems that need to be solved in the technique disclosed in Japanese Utility Model Publication No. 57-60071. For example, rii
In the J construction method, the end of each expanded diameter part in the pipe
Acceleration adjustment gas is supplied, thereby adjusting the flow velocity of the mixture 4 flowing in the pipe, increasing the speed of the abrasive by 1, and reducing the grinding performance due to a decrease in the density of the abrasive in the mixture 4. I'm trying to offset that. In other words, the density of the abrasive in the mixture decreases on the large-diameter pipe side, and the grinding ability also relatively decreases accordingly, but by increasing the flow rate of the mixture and increasing the kinetic energy of the abrasive, This is intended to offset the decrease in grinding and cleaning ability due to the decrease in abrasive material density.

Therefore, the diameter of each pipe it, 12, 13 is 13~
In the case of the 28th register use piping, it is possible to almost completely offset the decrease in the grinding and cleaning ability due to the decrease in the abrasive material density by adjusting the flow rate of the mixture.

However, if there is a pipe with a diameter of 3B or more in the regi-use pipe, it will be difficult to completely offset the decrease in grinding cleaning ability due to the decrease in the density of the abrasive material, and it will be very There is a problem that grinding spots are likely to occur on the diameter piping side.

Additionally, if the flow rate of the mixture on the large-diameter pipe side is increased in order to improve the grinding and cleaning effect, deep grinding streaks may be generated partially on the inner wall surface of the pipe, or damage due to deep grinding may occur on the inner wall surface of the curved part of the pipe. There is a problem in that it causes

Actually, since only the end of the expanded diameter part of the pipe/acceleration adjustment gas is supplied, it is impossible to grind and clean each branch pipe at the same time, which may cause problems in terms of work efficiency. Often.

The present invention is based on the above-mentioned Japanese Patent Publication No. 57-60071.
The objective is to solve the above-mentioned problems, and even in reuse piping consisting of piping sections with relatively large diameter differences, it is possible to achieve long piping without causing any damage to the inner wall surface of the pipe, and with high efficiency. The object of the present invention is to provide a method for cleaning the inner wall of a reuse pipe, which enables uniform grinding and cleaning over the entire length and cleaning of branch pipes at the same time.

The present invention injects a mixture of transport gas and abrasive material from the open end of the pipe on the small-diameter side of the pipe, and at the same time injects the mixture of transport gas and abrasive material from the open end of each branch pipe in the pipe. By supplying an adjustment mixture of gas and abrasive material and adjusting the supply amount of the adjustment mixture, the flow rate of the i'] iJ mixture flowing in the regiuse piping and its cleaning can be controlled. The basic configuration is to adjust the material density to the optimum value according to each pipe diameter.

Hereinafter, the details will be explained based on one embodiment of the present invention shown in the second embodiment (2!'l). .6
．． Reference numeral 7 denotes a branch pipe forming a part of the register use piping. Also, 14 is a compressor, 19 is a pressure regulator, 20
is a drain separator, and 2'1a to 210 are flow meters.

j5 has an abrasive material tongue, and the abrasive material 2 is silica sand (4~
6 houses) are being stored. Incidentally, in this embodiment, silica sand is used as the abrasive material 2, but it goes without saying that an abrasive material other than crushed sand may be used.

A mixing ejector 16 sucks appropriate silica sand 2 from the abrasive tank 15 and mixes it with the air flow.

17a to 17 (1 is an abrasive accelerator connected to the narrow diameter pipe 1a and each branch pipe 5,6゜7 with open ends, and a mixture of the air flow and silica sand coming out of the mixing ejector 16) A1
- The speed of the mixtures A1 to A4 is increased by injecting conveying air B1 to B4 into A4.

Reference numeral 18 denotes an abrasive material recovery device, which separates and recovers the abrasive material and solid matter such as exfoliated scale from the mixture of the conveying gas and the abrasive material that has passed through the reducer pipe.

A method for cleaning the inner wall surface of a pipe according to the present invention will be described.

First, start the compressor 14, and then turn on the pressure regulator 19.
The pressurized air adjusted to the pressure of ~101 is sent to each accelerator 171~
17 (1, mixing ejector 16 and abrasive tank 15
supply to Due to the pressurization of the tank I5 and the suction action of the ejector 16, a certain amount of silica sand 2 and air flow are sufficiently mixed, and the mixture of crushed sand 2 and air flow is supplied to 1 to A4 or each accelerator 17a to 17d. Ru. In addition, the mixing ratio of crushed sand 2 and air in the mixing tank 16 is 0.5 to 3 k.
VN horn i is set, and the mixing ratio is appropriately adjusted depending on the amount of scale on the inner wall surface of the pipe.

Each of the accelerators 171 to 17d and \ is supplied with the transport air flows B1 to B4 separately as described above, and by injecting the transport air flows B1 to B4 into the mixtures A1 to A4, the mixture is mixed. The bodies A1 to A4 become a high-speed swirling flow and are injected into the pipe.

In the present invention, first, from the open ( ) end of the pipe 1a on the small diameter side, the conveying gas and 0 [removal gas, which is formed by adding an appropriate amount of the conveying air Bl to the mixture A1 of air and crushed sand, At this time, the flow rate of the mixture to be injected into the pipe 931a is adjusted according to its diameter, and is usually set to a flow value within the range shown in the table below.

According to the experimental results, the mixing ratio of the abrasive material in the mixing ejector 16 [ζ] is 0.5 to 3 kg/Nyr? In this case, the flow rate of the mixture 4 is 37+ in piping size or IB.
iin, l 1/4 B 4.7 wfAin,
11/2 B and 6.8trtAin, 2 B and 1
2 tit/mvr, 3 B with 27 t)in or 6
It is optimal in terms of cleaning efficiency and prevention of damage to the inner wall surface of the pipe, and in the case of reuse piping, the density of the abrasive material in the mixture 4 flowing through each part of the pipe, that is, the mixing ratio of the abrasive material, is constant. It has been confirmed that the more uniform and spotless grinding and cleaning can be performed over the entire length of the piping.

First, adjust the valves 22a, 23a, and connect the piping la.
Adjust the flow rate of the mixture 4a flowing through the pipe 4a and its density (σ
The valve 23a was adjusted so that a was approximately 3 y & A-In, and the flow rate Qa' of the mixture A was determined from the difference between the flowmeter 21e and the flowmeter 211 (or the flowmeter 24a), and was set using the ejector 16. Crushed sand content S'(0,
Ha to 5-3? ? ) and the silica sand density S (Kri/Nfufu I'') in the mixture 4a flowing in the pipe la from the flow rate Qa'
I put it on.

Next, adjust the valves 22b and 23b to open the branch pipe 5.
The adjustment mixture 4b' is supplied into the pipe 1b, and the flow rate of the mixture 4b flowing inside the pipe 1b becomes a predetermined flow rate Q+), and the abrasive density of the mixture 41) is the above-mentioned S (K!/Nnl). The flow m of the adjustment mixture 4b' is approximately the same as
and adjust its crushed sand content.

Similar operations are performed on valves 22C and 23C as well as valve 22d.
, 23d, and the flow ffi of the mixtures 4a to 4d flowing in each piping section 1a to 1d of the register use piping.
A mixture 4 that flows through each of the distribution parts 1a to 1d while maintaining Qa - Qd at an optimal value according to each pipe size.
The inner wall of the pipe is cleaned while the abrasive material density of a to 4d is maintained at a substantially constant value.

In addition, in normal shelf-like register use piping, mixers 4b' to 4d adapted to the pipe size of each branch pipe 5.6.7 are used.
' By doing this, the flow rates Qb to Qd of the mixtures 4b to 4d in the pipes 11), IC, and 1d as well as the Cd sand density automatically become approximately optimal values, and the actual It is extremely convenient for construction. Further, in the embodiment, the valves 22a, 23a, the valves 22b, 23+
), valves 22C, 23C, valves 22d, 23d
If the valves are adjusted in the order of Needless to say, grinding and cleaning may be started under optimal conditions at the same time as compressed air is supplied from the machine.

Spray water is added to the mixture discharged from the maximum diameter pipe side of the regi-use piping before the recovery device 18, and the humidified mixture is separated from gas and solids (abrasive particles) in the recovery device comb 18. Separated into scavenging material → - scale).

In the above embodiment, the adjustment mixture 41)' to 4d' is supplied from the end opening of each branch pipe, but a separate opening is provided at the enlarged diameter end of the pipe 1. The invention is to supply the adjustment mixture to piping sections with different diameters in the register use piping through branch pipes, etc., and to supply the adjustment mixture from the conveying gas and abrasive material flowing in each piping section. The flow rate of the mixture is set to an optimum value according to the diameter of each pipe 11, and the density of the abrasive material flowing through each pipe section is kept approximately constant. As a result, it is possible to grind and clean the inner wall surface of the reuse piping more uniformly than any previous technology, and the processing length can be significantly extended, and the grinding and cleaning efficiency is greatly improved. .

Further, when the adjustment mixture is supplied from the opening at the end of the branch pipe, the branch pipe itself can also be cleaned, and the cleaning efficiency of the entire reuse pipe is greatly improved.

As mentioned above, the present invention has excellent practical utility.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is an implementation system diagram of a known cleaning method for regi-use piping. FIG. 2 is an implementation system diagram of the method for cleaning register use piping according to the present invention. A1-A4 Mixture B1-B4 Conveying gas S Abrasive material density 1 Registered use piping 13-1d Each piping path 2 of the registered reused piping Tilt
Sweeping paulownia 4a to 4d Mixture 41]' to 4d' Adjustment mixture 5.6.7 Branch pipes 17a to 17d Accelerators 22a to 22d Adjustment valves 23a to 23d Adjustment valve patent applicant

Claims (1)

[Claims] In the register use piping, a mixture of a conveying gas and an abrasive material is injected from the open 1'' end on the small diameter pipe side of the piping, and
By supplying the adjustment mixture of the conveying gas and the abrasive material from the open end of the → branch pipe in the piping, and adjusting the supply of the mixture for the 1i11'lth ik, the inside of the reuse piping is 1] Oral mixture flow (sha) and its (
0 [A method for cleaning the inner wall of a pipe for 7-use piping, characterized by adjusting the cleaning density to an optimal value corresponding to each pipe diameter.