JPH078427Y2 - Tanks lined with fluororesin - Google Patents

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to fluororesin-lined tanks. More specifically, the fluororesin liner may float from the inner peripheral surface of the tank even when used under negative pressure conditions. Not related to tanks lined with fluororesin.

Technical background of the invention and its problems Metal or general-purpose synthetic resin tanks cannot be used for corrosive fluids due to poor chemical resistance, and nest cases etc. adhere to the tank wall. Therefore, fluororesin lining tanks in which a fluororesin liner is provided on the inner peripheral surface of the tanks are used.

By the way, tanks are generally roughly classified into an open type and a sealed type. Of these, the open type will be described as an example. As shown in FIG. It is composed of a body 2 and a lower body 3. This upper lid 2
Has a flange portion 4 and a fluororesin first liner 5 on its inner peripheral surface.
A flare portion 6 is formed at the tip of the liner 5 along the flange portion 4 of the upper body 2. Similarly, the lower body 3 also has a flange portion 7 and a two-liner 8 of fluororesin or the like on its inner peripheral surface, and the flange of the lower body 3 is provided at the tip of the second fluororesin second liner 8. Part 7
A flare portion 9 is formed along the line. The upper body 2 and the lower body 3 as described above are joined by tightening the flange portions 4 and 7 of each other.

The upper body 2 and the lower body 3 of the tanks have openings A and B, respectively, if necessary.

Tanks lined with such fluororesin are
When the pressure of the liquid stored inside is a positive pressure higher than the normal pressure, it can withstand a considerably high pressure, but conversely, when the pressure inside the tank is a negative pressure lower than the normal pressure, FIG. As shown in FIG. 2, the fluororesin liner 8 floats up from the inner peripheral surface of the tank 3, and there is a problem that the fluororesin liner in the lifted part may crack.

Therefore, the applicant of the present application, on the inner peripheral surface of the fluororesin liner, to install an annular body made of a fluororesin having a reinforcing body inside, and to prevent the liner from rising. Fluorine resin lining tanks have already been proposed (see Japanese Utility Model Publication No. 62-127,982).

However, when the temperature of the fluid used in the tank is high and the fluororesin liner cannot be completely prevented from rising under high vacuum conditions, the annular body may sometimes fall off, and further improvement is required. Was desired.

The purpose of the present invention is to solve the problems associated with the prior art as described above, and to prevent the fluororesin liner from rising from the inner peripheral surface of tanks, and particularly to the negative pressure resistance characteristics. It is intended to provide excellent fluororesin-lined tanks.

SUMMARY OF THE INVENTION Tanks lined with a fluororesin according to the present invention include tanks whose inner peripheral surface is covered with a fluororesin liner, on the inner peripheral surface of the fluororesin liner.
A coil-shaped annular body made of fluororesin having a reinforcing body embedded therein is mounted, and the fluororesin rib adhered to the inner peripheral surface of the fluororesin liner intersects and engages with the annular body. It is characterized by being configured as follows.

In the fluororesin-lined tanks according to the present invention, a coil-shaped annular body made of fluororesin having a reinforcing body embedded therein is mounted, and the annular body has an inner peripheral surface of the fluororesin liner. Since the fluororesin rib adhered to the crossing is configured to engage with each other, the fluororesin liner floats up from the inner peripheral surface of the tanks,
It does not peel off, and the annular body itself does not fall off from the inner peripheral surface of the liner.

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described below based on embodiments shown in the drawings.

FIG. 1 is a sectional view showing an embodiment of the present invention.
1 is an enlarged cross-sectional view showing FIG. 1 in more detail, and in the following description, the same members as those shown in FIG. 5 are designated by the same reference numerals.

The present invention will be described by taking open tanks as an example. As shown in FIG. 1, the tanks 20 are composed of an upper body (particularly an upper lid body) 2 and a lower body 3. The upper lid body 2 has a flange portion 4 and a fluororesin first liner 5 on the inner peripheral surface thereof, and the tip portion of the fluororesin first liner 5 extends along the flange portion 4 of the upper lid body 2. Flare portion 6 is formed. Similarly, the lower body 3 also has a flange portion 7 and a fluororesin second liner 8 on its inner peripheral surface. A flare portion 9 is formed along the flange portion. The upper lid 2 and the lower body 3 as described above are joined by tightening the flange portions 4 and 7 of each other.

The upper lid 2 and the lower body of the tanks 20 may have openings A and B, respectively, if necessary.

The fluororesin forming the liner is PTFE, vinylidene fluoride (PVDF) or PF which is a copolymer of tetrafluoroethylene and perfluoroalkyl vinyl ether.
A, FEP, which is a copolymer of tetrafluoroethylene and propylene hexafluoride, and ETFE, which is a copolymer of tetrafluoroethylene and ethylene, are used. Of these, PTFE is most preferable because of its high reliability as a liner.

Any method may be adopted to manufacture the fluororesin liners 5 and 8 having a shape along the inner peripheral surfaces of the upper lid 2 and the lower body 3 of the tanks 20. For example, fluorocarbon resin
In the case of non-heat-melting fluororesin such as PTFE, a core is placed along the inner peripheral surface of the upper lid or the lower body that encloses a flexible diaphragm having a shape similar to the inner peripheral surface. After filling the gap between the diaphragm and the inner peripheral surface with PTFE powder, a liquid such as water is pressed into the upper lid or the lower body from the core to inflate the diaphragm and press-contact the inner peripheral surface with the PTFE liner. Preformed,
A so-called hydraulic molding method is adopted in which the obtained preformed liner is placed in a heating furnace and heated and baked at a temperature higher than the melting point of PTFE.

Further, in order to manufacture the fluororesin liners 5 and 8,
The fluorocarbon resin sheet is joined in advance, and the tank upper lid 2
Alternatively, the liners 5 and 8 having the same shape as the inner peripheral surface of the lower body 3 are completed, and after the liners 5 and 8 are drawn into the tank, the liners 5 and 8 are adhered to the inner peripheral surface of the tank to lining them. The pull-in lining method (tentative name) is also adopted.

Further, there is also adopted a method in which the fluororesin sheets lined with a glass cloth are sequentially laminated to the inner peripheral surface of the tanks 20 and the joining portions of the sheets are melt-bonded with a fluororesin welding rod.

In this embodiment, an annular body 22 made of fluororesin having a reinforcing body 21 embedded therein is inserted and extended on the inner peripheral surface of the fluororesin liner 8 in a coil shape.

The coiled annular body 22 is mainly inserted and installed on the inner peripheral surface of the fluororesin second liner 8 provided on the inner peripheral surface of the lower body 3 of the tanks 20. The outer diameter is substantially equal to the inner diameter D of the tanks 20 in which the second liner 8 is lined, and the coiled annular body 22
Is the straight part of the lower body 3 of the tanks 20 (body part)
It is preferable that the length L is set to be slightly shorter than the length L.

To form the coiled annular body 22, for example, a reinforcing body is used.
A fluororesin tube may be inserted around the outer periphery of 21 and both ends of the reinforcing body 21 may be fusion-sealed with a fluororesin blind plug (not shown). In this way, the coil-shaped annular body 22 in which the reinforcing body 21 is completely covered with the fluororesin is formed.

The fluororesin forming the annular body 22 includes PTFE and PVD.
F, PFA, FEP, ETFE and the like are used, and among these, PTFE and PFA are particularly preferable.

The reinforcing body 21 embedded in the coil-shaped annular body 22 is preferably made of a metal having elastic expansion habit, whereby the fluororesin liners 5 and 8 are formed from the inner peripheral surface of the tanks 20. Can be prevented from being lifted and peeled off, and the annular body itself does not fall off.

As the metal reinforcing body, for example, a belt-shaped body, a rod-shaped body, or a linear body made of various metal materials such as a general steel material, a wire rope, and a carbon steel wire for springs is applied. However, the material is not limited to metal, and various heat resistant plastics or composite materials thereof can be used.

By doing so, even if the tanks 20 are used in a high vacuum condition where the fluid temperature is high, the first and second liners 5 and 8 provided on the inner peripheral surfaces of the tanks 20 have a coiled annular shape. Since the body 22 presses the inner peripheral surface of the straight body portion of the liner 8, the liner 8 and the like are prevented from rising.

The coiled annular body 22 does not necessarily need to elastically press the inner peripheral surface of the liner 8 and may be simply an abutting upper body.

Further, in the tanks 20 of this embodiment, the tanks shown in FIG.
As shown in detail in FIG. 3 showing a cross section taken along the line III-III in the figure, a fluororesin rib 23 is adhered to the inner peripheral surface of the tanks 20. The fluororesin ribs 23 have recesses formed at predetermined intervals, and the annular body 22 is accommodated in the recesses so that the annular body 22 intersects with the coil-shaped annular body 22.
22 is engaged.

Four fluororesin ribs 23 are provided in the height direction of the tanks 20 orthogonal to the coiled annular body 22. Each of the fluororesin ribs 23 is provided with a recess 24 at an intersecting portion orthogonal to the coil-shaped annular body 22, and a part of the coil-shaped annular body 22 is housed in the recess 24. The second liner 8 is prevented from floating and the second
The fluororesin rib 23 and the fluororesin second liner 8 are adhered to the liner 8 entirely or partially so as to be in close contact with the liner 8. As the bonding method, a welding method using a hot-melt fluororesin is preferable. For example, when the second liner 8 is PTFE, the ribs 23 are also preferably PTFE. In this case, it is better to use a PFA welding rod for fusion bonding.

FIG. 4 shows another embodiment of the present invention, in which the coiled annular body 22 is supported from the inside.

The coiled annular body 22 is mainly attached to the inner peripheral surface of the fluororesin second liner 8 provided on the inner peripheral surface of the lower body 3, but is provided on the inner peripheral surface of the upper lid body 2. It is also possible to provide it on the fluororesin first liner 5.

The present invention can also be applied to pipes other than tanks, reaction towers, and the like.

Effect of the Invention In the fluororesin-lined tanks according to the present invention, a reinforcing body is embedded inside the tank, which extends in a coil shape on the inner circumferential surface of the fluororesin liner provided on the inner circumferential surface of the tanks. Since the annular body made of fluororesin is provided, and the annular body is constituted so that the fluororesin ribs adhered to the inner peripheral surface of the fluororesin liner intersect and engage with each other, the fluororesin liner is used as a tank. It does not rise or peel off from the inner peripheral surface of the class, and the annular body itself does not fall off.

Further, when the annular body is supported by the fluorine resin rib provided on the inner peripheral surface of the fluororesin liner, the floating of the fluororesin liner and the detachment of the annular body can be more effectively prevented.

[Brief description of drawings]

FIG. 1 is a sectional view of an open type tank showing an embodiment of the present invention, FIG. 2 is a vertical sectional view showing the embodiment in more detail, and FIG.
2 is a sectional view taken along the line III-III in FIG. 2, FIG. 4 is a longitudinal sectional view of an essential part showing another embodiment of the present invention, and FIG. 5 is a sectional view of a conventional open tank. FIG. 6 is a sectional view showing a state in which the liner in the open tanks of FIG. 5 is lifted. 2 ... Upper lid, 3 ... Lower body, 5 ... First liner, 8 ... Second
Liner, 20 ... Tanks, 21 ... Reinforcement body, 22 ... Annular body, 23
…rib.

Claims (1)

[Scope of utility model registration request] 1. In a tank having an inner peripheral surface covered with a fluororesin liner, a coiled annular body made of fluororesin having a reinforcing member embedded therein is mounted on the inner peripheral surface of the fluororesin liner. In addition, the tanks lined with a fluororesin are characterized in that the annular body is constituted so that fluororesin ribs adhered to the inner peripheral surface of the fluororesin liner intersect and engage with each other. .