JPH0340323Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention relates to a bubble separator for high viscosity fluids.

(b) Prior art Polymer fluids such as polyvinyl chloride plastisol (hereinafter referred to as "PVC plastisol"), rubber latex compounds, polyvinyl acetate latex, etc. are used to manufacture daily necessities, sporting goods, industrial materials, etc. It is widely used in

Among the various products mentioned above, for example, a relatively large amount of vinyl chloride plastisol is used in manufacturing underpads for artificial turf, stepping mats, nets for ball games, and the like.

These products, such as underpats for artificial turf and foot mats, are made of gelled vinyl chloride that swells high on the top surface of synthetic fiber nets, and nets for ball games are made of synthetic fiber nets with gelled polyvinyl chloride raised high on the top surface. The PVC plastisol used during the manufacturing process must be non-thixotropic and extremely viscous.

When manufacturing the above-mentioned products, the prepared vinyl chloride plastisol is first supplied to an apparatus for manufacturing the product.

At this time, the PVC plastisol is supplied by a pump. When using a high viscosity fluid like the above-mentioned product, a screw pump is often used.
Although it is not limited to the case where the fluid is supplied by a screw pump, in any case, when the fluid is sent by a pump, a large amount of large and small air bubbles are mixed into the sent fluid. Such a phenomenon cannot be avoided even if PVC plastisol is completely defoamed before pumping.

When PVC plastisol containing large and small air bubbles, especially large air bubbles, is supplied to the product manufacturing equipment to produce a product, large depressions or localized large bulges may occur on the surface of the product. This not only degrades the appearance, but also impairs performance and reduces product value.

(c) Problems to be solved by the invention Conventionally, in an attempt to remove air bubbles in the thixotropic and extremely viscous PVC plastisol, as described above, the method of dropping the air along an inclined surface and using a vacuum defoaming machine have been proposed. Methods have been considered for degassing, but in either case they had drawbacks, such as being too time consuming, being able to be carried out only in small quantities, and not being able to degas sufficiently.

The object of the present invention is to provide a bubble separator that can solve the above-mentioned drawbacks at once and that can continuously separate bubbles in a high-viscosity fluid.

(d) Means for solving the problem The bubble separator of the present invention has a discharge port 1 in the upper part, as shown in the longitudinal cross-sectional view of FIG. 1 and the cross-sectional view taken along line A-A in FIG. a sealed outer cylinder 2 having a
It consists of an inner cylinder 5 which penetrates the inside of the outer cylinder 2 and is fixed at both ends 3 and has both ends 4 open.
The gist is that an appropriate number of holes 6 are bored in the pores 6, and that air bubbles in a high viscosity fluid can be continuously and reliably separated.

Note that the upper and lower portions of the inner tube 5 exposed from the inside of the outer tube 2 are portions that are connected to an injection hose, a recovery hose, etc., respectively.

(E) Function and Effects The inventor conducted the following experiments before completing the present invention.

This will be explained with reference to FIGS. 3 and 4, which are schematic longitudinal sectional views.

First, the explanation will be given with reference to FIG. When the high viscosity fluid 7 that does not contain air bubbles is pumped from the bottom to the top into the tube 8, the flow velocity distribution of the high viscosity fluid 7 is distributed as shown by the arrow 10 extending vertically upward from the top of the line 9. However, it is finally represented by a curve 11 connecting the vertices. That is, the flow velocity of the high viscosity fluid 7 is high in the center of the pipe 8 and low near the inner wall of the pipe 8.

Next, the case where the highly viscous fluid 7 containing a large number of large and small bubbles almost uniformly is pumped from the bottom to the top into the tube 8 will be explained with reference to FIG. 4, and the flow velocity distribution will be as follows.
It is distributed like an arrow 12 extending vertically upward from the line 9, and is ultimately represented by a curve 13 connecting the vertices.

When curve 11 and curve 13 representing the flow velocity distribution are compared, the latter extends extremely upward in the center of the pipe 8. In other words, this indicates that the flow velocity is higher in the central part of the latter than in the former. Here, when examining the latter, that is, the high viscosity fluid at each part on curve 13, it is found that large and small bubbles are concentrated in the central part where the flow velocity is high, while on the other hand, in the parts near the peripheral wall where the flow velocity is low. It was found that almost no air bubbles were included because the large and small air bubbles had moved to the center.

Therefore, the present inventor made a hole in the wall of the tube 8 (which corresponds to the inner tube 5 in FIGS. 1 and 2),
Only the high viscosity fluid that does not contain air bubbles existing near the wall is extracted, and only the high viscosity fluid separated from the pores is supplied to the manufacturing equipment, where high viscosity is required during the process. It was used in a product.

In the actual process, the separator of the present invention as shown in Figures 1 and 2 is prepared, and the high viscosity fluid is simply pumped from one end to the other.
It is possible to continuously obtain a high viscosity fluid that does not contain bubbles one after another.

(F) Example: PVC plastisol used for baseball field artificial turf underpads was coated with a paint roll using the following composition.
200Kg was adjusted in 3 batches.

Vinyl chloride resin for base (F=800
~900) 100 parts by weight Plasticizer DOP 65 parts by weight Plasticizer BBP 13 parts by weight Stabilizer (epoxy compound) 5 parts by weight Stabilizer (barium/zinc-based composite)
2.5 parts by weight Blowing agent (azo compound) 2.5 parts by weight Thixotropic agent (colloidal hydrous aluminum silicate organic complex) 2 parts by weight Filler (fatty acid treated calcium carbonate)
20 parts by weight Viscosity V ₂ : 300,000 CPS V ₄ : 180,000 CPS Yield value 4,800 dyne/cm ² Measured with a BH type viscometer and No. 6 rotor was used.

Three batches of the PVC plastisol were placed in one can containing approximately 600 kg and stirred in order to eliminate variations among the batches.

A screw pump (not shown) is used to remove the bubble separator of the present invention shown in FIG.
(16 holes 6 with a diameter of 15 mm are bored almost equally in the inner cylinder 5 existing inside) is fed under pressure into the inner cylinder 5 at a rate of 5 to 10 kg/cm ² , and then, The vinyl chloride plastisol discharged from the hole 6 of the inner cylinder 5 was taken out from the discharge port 1 and used for an underpad for artificial turf of a baseball field.

Although this underpad had an appropriate elasticity, no large depressions or large localized bulges were formed on the surface of the product.

Therefore, it can be seen that the PVC plastisol used does not contain any air bubbles.

On the other hand, the PVC plastisol that has flowed out from above the inner cylinder 5 contains many large and small air bubbles.
The mixture was mixed with freshly prepared PVC plastisol and used again through a recovery hose (not shown) connected to the exposed part of the outer cylinder 2 of the PVC.

In this example, the amount of PVC plastisol pumped into the inner cylinder 5 by the screw pump is 12.4
In the case of Kg/min, the amount of PVC plastisol coming out from the discharge port 1 is 7 Kg/min, and the amount going from the upper part of the inner cylinder 5 to the recovery hose is 5.4 Kg/min. If the amount of PVC plastisol pumped into the inner cylinder 5 by the pump is 7.25 kg/min, the amount of PVC plastisol coming out from the discharge port 1 is 5.25 kg/min.
Kg/min, the amount going from the top of the inner cylinder 5 to the collection hose is
It was 2.0Kg/min.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of the bubble separator for high viscosity fluid according to the present invention, Fig. 2 is a sectional view taken along the line A-A, and Fig. 3
4 and 4 show schematic vertical cross-sectional views of the flow velocity distribution of the pipe and the fluid for explaining the effect thereof. DESCRIPTION OF SYMBOLS 1... Discharge port, 2... Outer cylinder, 3... Both ends of outer cylinder 2, 4... Both ends of inner cylinder 5, 6... Hole, 7... High viscosity fluid, 8... Pipe, 9 ...line, 10,1
2...Arrow, 11, 13...Curve.

Claims (1)

[Scope of utility model registration request] It consists of a sealed outer cylinder 2 having a discharge port 1 at the upper part, and an inner cylinder 5 with open ends 4 that penetrates the inside of the outer cylinder 2 and is fixed at both ends 3.
A bubble separator for high viscosity fluids, in which an appropriate number of holes 6 are bored.