JPH0350597B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a pipe cleaning method for removing and purifying scale and dirt deposits generated on the interior, especially the inner surface, of metal pipes and other piping. It is related to.

[Conventional technology]

Conventionally, this type of cleaning to remove deposits inside a pipe has been carried out by installing a spray nozzle at the pipe inlet to spray compressed gas mixed with an abrasive, or by providing a swirling device to give the pipe a swirling motion.

[Problem that the invention seeks to solve]

In all of these methods, the flow velocity is high in the center of the pipe cross section, and the flow velocity decreases on the inner wall side of the pipe where the abrasive material collides with the deposits inside the pipe, so the deposit removal effect is poor, or the abrasive material is mixed into the compressed gas. There were drawbacks such as the need for a pressure-feeding device.

In order to eliminate this drawback, the present invention installs an annular swirling flow generator upstream of the abrasive mixing inlet, increases the flow velocity on the inner wall side of the pipe, increases the momentum of the abrasive, and enhances the grinding effect. The present invention provides a method for removing deposits in piping that uses the ejector effect of the abrasive material caused by the flow to omit an abrasive material feeding device, thereby increasing workability and reducing processing costs.

[Means for solving problems]

The present invention is a method of supplying compressed gas mixed with an abrasive into the piping to remove and clean deposits inside the piping. Compressed gas is passed through the swirl flow generator through the header and supplied along the inner wall of the pipe, while the abrasive is compressed from a supply port connected to the downstream outer wall of the swirl flow generator provided in the pipe. The abrasive material is suction-mixed into the compressed gas by the ejector action of the annular swirl flow generated by the swirl flow generator, and the compressed gas mixed with the abrasive material is mixed along the inner wall of the pipe. This piping cleaning method is characterized by passing the piping in an annular swirling flow.

〔Example〕

The embodiment shown in FIG. 1 uses air compressed by a compressor as the compressed gas, and the compressor 1 serving as the compressed air source supplies the compressed air to the pipe A through the header 2. Annular swirl flow generator 3 installed at the inlet of pipe A
It is designed to be pumped to As shown in Fig. 2, this annular swirling flow generating device 3 is constructed so that an annular swirling flow is generated in the axial flow by a guide vane (swirling generation plate) 3 ₁ and a boss 3 ₂ in the duct, and this swirling A supply port 5 communicating with the storage tank 4 for the abrasive material B is provided downstream of the plate ₃₁ , so that the abrasive material B is mixed into the annular swirling flow. That is, after the compressed air once gathers in the header 2, it becomes an annular swirling flow by the annular swirling flow generating device 3, and the abrasive material B is sucked and mixed by the ejector effect, and then it is forced into the piping and removes the deposits C inside the pipe. remove.

In addition, a developed view of the annular swirl flow generator 3 (third
As shown in the figure, a rotation generating plate 3 ₁ is attached to a central cylindrical boss 3 ₂ . Abrasive material B is deposited inside the pipe C
It flows while repeatedly colliding with each other, and the larger the momentum, the more effective it is in grinding the deposits C. Generally, the velocity distribution of the developed turbulent flow in a circular pipe is large in the center of the pipe and slows down near the pipe wall due to the influence of viscosity, so the flow velocity of the abrasive material also decreases near deposits, reducing the grinding effect. However, according to the annular swirl flow generating device 3 of the present invention, a large grinding effect can be expected because the flow velocity near the pipe wall is relatively high compared to the central part.

Furthermore, since the abrasive material B is sucked and mixed by the ejector effect, no pumping device for the abrasive material B is required.

Furthermore, compared to the case where compressed gas mixed with the abrasive B is fed under pressure while maintaining the same pipe diameter, the flow is accelerated in this generator section, so there is an effect similar to that of an injection nozzle.

Note that an inert gas such as N ₂ gas can be used as the compressed gas, and it can be supplied not only from gas compressed by a compressor but also from a liquid or a high-pressure cylinder.

〔Effect of the invention〕

The present invention installs an annular swirling flow generator at the inlet of a pipe from which deposits are to be removed, gives compressed gas mixed with an abrasive an annular swirling motion, removes deposits in the pipe, and generates the same annular swirling flow. By suctioning the abrasive material by the ejector effect caused by the flow and mixing it with the compressed gas, the compressed gas mixed with the abrasive material is turned into an annular swirling flow to enhance the grinding effect of the deposits inside the pipe. The abrasive material is safe because it does not get worn out or damaged, and generates little noise. Furthermore, since the abrasive material is introduced from the supply section that communicates with the outer wall, it is immediately mixed into the swirling flow that flows along the inner wall of the pipe, and is deposited on the inner wall of the pipe. Because they are conveyed in contact with each other, the polishing effect is great and removes deposits from the pipe wall surface.
It is highly effective, helps reduce the amount of abrasive, and since the abrasive is sucked by the ejector effect, an abrasive pumping device is not required.

[Brief explanation of drawings]

FIG. 1 is an inventive drawing of the cleaning method according to the present invention in a lathe state, FIG. 2 is a longitudinal sectional view taken along the line of FIG. 1, and FIG. 3 is a developed view of the turning generation plate. 1... Compressor, 2... Header, 3... Annular swirl flow generator, 4... Storage tank, 5... Supply port, A... Piping, B... Abrasive material, C... Deposit.

Claims (1)

[Claims] 1 In a method of supplying compressed gas mixed with an abrasive into the piping to remove deposits inside the piping, a swirl flow generator is installed at the entrance of the piping to supply compressed gas from a compressed air source. The abrasive is supplied along the inner wall of the pipe through the header through the swirl flow generator, while the abrasive is supplied to the compressed gas from a supply port connected to the outer wall on the downstream side of the swirl flow generator provided in the pipe. The abrasive material is suction-mixed into the compressed gas by the ejector action of the annular swirl flow generated by the swirl flow generating device, and the compressed gas mixed with the abrasive material is swirled annularly along the inner wall side of the pipe. A pipe cleaning method characterized by passing through the pipes with a stream.