JPS587874B2 - Piping corrosion protection mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION At present, air conditioning equipment, hot water supply systems, etc. are indispensable in hospitals, hotels, condominiums, etc., and the piping equipment therefor has become large-scale.

However, the pipes corrode within two to four years, resulting in red water.

Therefore, the inventor of the present application first invented a corrosion protection mechanism.

The specific structure of this anti-corrosion mechanism will be explained with reference to FIGS. 1 and 2.

Front and rear plates 2 and 3 are welded to both ends of the cylindrical expansion part 1, and a water supply pipe 4 is attached to the upper part of the front plate, and a discharge pipe 5 is attached to the lower part of the rear plate.

A heat exchanger such as a boiler and an impeller pump B (see FIG. 3) are connected to the mounting flange of the water supply pipe 4, and a pipe 7 is also connected to the flange at the open end of the discharge pipe 5. ing.

The inner diameter of the expansion part 1 is determined by the amount of water flowing in from the pipe 6, the flow velocity, the state of turbulence, etc., but according to experiments, it is approximately twice to 5.5 times the inner diameter of the water supply pipe 4 (or pipe 6). is the most desirable.

If the inner diameter of the expansion part 1 is about 1.5 times the diameter of the water supply pipe 4, it will not be sufficient to remove air bubbles from the water, and if the diameter ratio is abnormally large, such as a storage tank, for example, if it exceeds 6 times, the water will become turbulent. The flow state is no longer resolved, there is no separation of bubbles, and no anticorrosion effect is exhibited.

Furthermore, it is most desirable to make the axial length of the expansion part 1 about 4 to 9 times its diameter in terms of the bubble removal effect of the flowing water and the manufacturing cost.

In this way, the flow rate of water supplied from the water supply pipe 4 via the pipe 6 is reduced to about one-tenth when passing through the expansion section 1.

Furthermore, welding points 1a between the end sides of the expansion part 1 and the front and rear plates 2 and 3
, lb should not be arcuate, but should preferably be rectangular as shown in the second figure.

If these welding points 1a, lb are formed in an arc shape,
The flow of hot water W flowing in from the water supply pipe 4 will create a swirl along the arc of the welding location, and the sound waves will not disappear, potentially making it impossible to achieve the object of the present invention.

Next, on a part of the upper surface of the inflatable part 1 on the downstream side, that is, near the rear plate, a cushion cylinder 8 having an inner diameter substantially the same as the inner diameter of the inflatable part 1 is protruded in a communicating state.

The height of the cushion tube 8 is preferably at least the same length as the inner diameter of the inflatable portion 1 or longer.

This is to fully exhibit the cushioning effect described later.

An air vent pipe 9 is vertically provided in the middle of the top plate of the cushion tube 8, and an automatic air vent 10 is provided in this air vent pipe.

In this case, the lower end of the ventilation pipe 9 is 2 times higher than the height of the cushion cylinder 8.
It penetrates to about 1/4 to 4/5 and is fixed.

Therefore, air remains at the outer peripheral portion of the lower end of the air vent pipe 9 to form a cushion portion 8a.

The air extraction pipe 9 must be installed so that the axis of the pipe is located inward from the rear plate 3 of the inflatable part by 1/10 to 4 times the total length of the inflatable part 1.

If the position of the air vent pipe 9 is varied, the noise and pattern generated by the pump will change, so it is necessary to determine the optimum position based on the capacity of the cushion portion 8a, etc.

For example, if the length of the expansion part 1 in the axial direction is specified as 550 mm,
Assuming that the inner diameter of the cushion tube 8 is a1, and the distance from the rear plate 3 to the axis of the ventilation pipe 9 is b1, then a is 50.65, 80.
, 100, 150, b is 75, 82.5, 9
The most desirable values were 0.5, 100, and 125.

Further, the outer diameter of the air vent pipe 9 is related to the inner diameter of the cushion tube 8, but it is natural that it must be such that it does not at least impede the cushioning effect.

Therefore, an example of actually using the anti-corrosion device D will be explained based on FIG. 3.

The amount of water supplied from the cistern S is constantly controlled by a ball tap T, and the water from this cistern is sent through a pipe to a boiler B, where it is heated and, if necessary, sent to a corrosion protection device D by a pump.

Hot water W flows into the expansion part 1 from the water supply pipe 4 and flows into the expansion part 1 through the discharge port 5.
Although some of the hot water is discharged, the cushion cylinder 8 is filled with warm water because the amount of inflow is greater than the amount of hot water discharged.

The water flowing in from the water supply pipe 4 is in a turbulent state, but when it flows into the expansion part 1, the flow rate is attenuated, and dissolved gas becomes bubbles and begins to stay in the cushion cylinder 8, and some of them are exhausted from the air exhaust pipe 9. be done.

If this state continues, air bubbles will fill the lower end outer periphery of the air vent pipe 9 within the cushion tube 8, and a cushion portion 8a will be formed as shown in the second figure.

The separated air bubbles remain in the cushion portion 8a, but excess gas passes through the air vent pipe 9 and is discharged to the atmosphere by the air vent 10.

In this way, the bubbles are separated and the hot water with suppressed wave motion passes through the pipe 7 arranged from the discharge pipe 5 to the hot water supply equipment 12.
etc.

Next, we will explain the reason why red water does not come out, that is, why rust does not form on the inner walls of the pipes.

First, a part of the pipe 7 was cut in the middle, sampled, and analyzed, and it was found that an anti-rust coating had been formed on the inner wall of the pipe.
It was found that the cause of this was the effect of suppressing wave motion in flowing water by this anti-corrosion device D.

To be more specific about this point, when water is supplied using a commercially available impeller pump, approximately 50 to 30
It has a frequency of 0 Hz and an amplitude value of 35 to 70μ, but after passing through the anti-corrosion device D, the amplitude value becomes approximately one-third or less, that is, approximately 8 to 18μ, and this amplitude value is
When the waves propagate, they begin to fuse with the heavy metals in the warm water, and as a result, a hard anti-rust coating is formed on the inner surface of the pipe, preventing corrosion of the pipe.

To prevent corrosion of this pipe, experimental results show that when water is supplied by cistern S as shown in Figure 3, it is extremely difficult to form a rust preventive film if the amplitude value passing through anticorrosion device D is 8 μ or less. On the other hand, it has been found that if the thickness exceeds 18μ, not only will the formation of the anti-rust coating not occur, but the coating that has already been formed will be destroyed.

Analysis of the rust-preventive coating attached to the inner surface of the copper tube 7 revealed that 24.20% silicic acid, 9.92% aluminum oxide and ferric oxide, 0.10% calcium oxide, and 0.10% magnesium oxide. 0.04%, zinc oxide 43.97%, and copper oxide 6.43%.

Furthermore, the generation of red water can be stopped even if a corrosion prevention device D is interposed in the pipe from which red water is coming out.

Incidentally, the relationship between the capacity of the water supply pump and the use of the cistern is important in setting the capacity of the corrosion protection device D.

For example, when an impeller type pump is used and the pump has a water delivery capacity of 100 liters per minute, a corrosion protection device D with a capacity corresponding to this must be selected and applied.

Furthermore, when using anti-corrosion device D in an air conditioner, a pump with a predetermined capacity is used to constantly supply a predetermined amount of hot water, but in the case of a water heater, it is not necessary to constantly supply a predetermined amount of hot water. , the number of pumps used in air conditioning equipment is 100
Assuming l/m, for example, 25 l/min or only Cistern S is sufficient.

On the other hand, if the anti-corrosion device D is made too small, air bubbles will not be separated sufficiently and it will be impossible to prevent the generation of red water.

Therefore, if the capacity of the impeller pump is 25 l/min, the amplitude value of the frequency in the water supply W is approximately 8 to 15 μ, and if this water is directly supplied to the corrosion protection device D, the amplitude value is 2 to 5 μ.
In this case, it is impossible to form a rust preventive coating as described above.

The present invention has been improved in this regard, and as shown in the second figure, an amplifier 11 is provided inside the water supply pipe 4 (or may be near the water supply pipe).

As described above, the present invention poses a problem when a pump having a water supply capacity lower than the capacity of the anti-corrosion device D is used, such as a cistern S only or a water heater.

By the way, the amplifier 11 may use a resonator plate and cause resonance and amplification by the resonator plate having a natural frequency that matches the frequency in the water supply, but the structure shown in FIG. 4 may also be used.

The amplifier 11 shown in FIG. 4 has a tuning fork-shaped vibrating body 13 inserted into a water supply pipe 4 made of iron, and this vibrating body is insulatively fastened to the water supply pipe via a packing 14.

A coil 15 is wound around the vibrating body 13.
By passing a current through this coil, a magnetic pole change occurs between the tuning fork-shaped leg 13a and the water supply pipe 4, and this leg vibrates, thereby increasing the amplitude value of the water supply W.

As described above, even when the water supply does not have a predetermined amplitude value, the present invention can give a predetermined amplitude value to the water supplied to the pipe, and form a rust-preventing film on the inner wall surface of the pipe, thereby preventing the generation of red water. It is something that can be prevented.

[Brief explanation of drawings]

Figure 1 is a plan view, Figure 2 is a sectional view along the line ■-■ in Figure 1, and Figure 3 is a plan view.
The figure is a wiring diagram, and FIG. 4 is an enlarged sectional view of main parts. 1... Expansion section, 2... Front plate, 3...
... Rear plate, 4 ... Water supply pipe, 5 ... Discharge pipe, 8 ... Cushion tube, 8a ...
Cushion part, 9...Exhaust tube, 11...
- Amplifier, D...corrosion protection device.

Claims (1)

[Scope of Claims] 1. A hollow expansion part having a water supply pipe on the front plate and a discharge pipe on the rear plate, and an air cushion cylinder projecting in communication with a part of the upper surface of the expansion part near the rear plate. In the anticorrosion mechanism, which is composed of an air vent pipe that is vertically installed on the top plate of the air cushion tube and forms a cushion portion on its outer periphery, an amplitude device is provided in the water supply pipe to increase the amplitude value of the water supply. A corrosion protection mechanism for piping characterized by: