CN218477987U - Corrosive chemicals storage jar - Google Patents

Abstract

The utility model relates to the field of wet chemical storage for semiconductors, in particular to a corrosive chemical storage tank, which comprises a tank body, a tank body and a neck part, wherein the tank body comprises a tank main body and a neck part; a fluorine plate bonded to an inner surface of the can body; a fluorine-lined tube extending through the neck; the welding block is welded with the fluorine plate and the fluorine lining pipe to form a seal; the tank body is provided with a groove part at the joint of the tank main body and the neck part; the end, close to the inner lining fluorine pipe, of the fluorine plate is abutted against the outer wall of the inner lining fluorine pipe to form an inclined part positioned in the groove part. Bond on inside lining fluorine pipe and fluorine board through the welding piece melting to the realization is to playing sealed effect between inside lining fluorine pipe and the fluorine board, avoids the inside liquid of storage tank to permeate from the two junction, avoids its metal ion to wet chemicals to pollute, guarantees the purity of the wet chemicals of storing.

Description

Corrosive chemicals storage jar

Technical Field

The utility model relates to a semiconductor is with wet chemicals storage field especially relates to a corrosive chemicals storage jar.

Background

The semiconductor manufacturing industry is a chemically closely related process in which a wide variety of ultra-high purity chemicals are required, and wet chemical reagents are essential key raw materials for the semiconductor processing chain. Many liquids are used in the wet processing steps of semiconductor manufacturing, and the used chemicals are often acid or alkaline and corrosive to conventional metal tanks; and the semiconductor industry has extremely high purity requirements for these chemicals, requiring electronic levels, typically below parts per billion (ppb) or parts per trillion (ppt).

Ordinary storage tank can't satisfy the requirement that semiconductor trade stored with corrosive chemicals, needs to do on the storage tank and does anticorrosive to solve its problem. For example, the storage tank lining anticorrosion technology is mainly divided into a lining welding forming technology, a lining winding forming technology, a lining isobaric forming technology, a lining three-dimensional rotation forming technology, a forming technology with metal grids, a light plate loose lining and a composite forming technology.

The lining isobaric molding technology adopts an elastic mold for molding, the inner wall and the outer wall of the lining part in the cavity of a workpiece are under an isobaric difference condition, the elastic mold fully utilizes the elasticity of the elastic mold to compress and cling the PTFE powder filled in the cavity to the lining wall, the thicknesses of the PTFE linings are kept consistent, the problems of difficult mold making technology of the inner cavity of the workpiece with a complex shape and inconsistent lining thicknesses are completely solved, cracks caused by local stress concentration can be prevented, and the problem that the local stress concentration causes the cracks due to inconsistent curing reaction speed in the sintering process is overcome. In use, it has been found that the location of the tank liner portion at the tank neck junction is susceptible to penetration by corrosive liquids inside the tank, causing corrosion of the tank and resulting in affecting the purity of the wet chemical, and this application is made.

Disclosure of Invention

The utility model aims to solve the technical problem that the prior art is not enough to be overcome, and a corrosive chemicals storage jar is provided.

In order to achieve the purpose, the utility model adopts the technical scheme as follows:

a corrosive chemical storage tank, comprising:

a can body comprising a can body and a neck;

a fluorine plate bonded to an inner surface of the can body;

a fluorine-lined tube extending through the neck;

a welding block which is welded with the fluorine plate and the fluorine lining pipe to form a seal;

the tank body is provided with a groove part at the joint of the tank main body and the neck part; the fluorine plate is close to the end of the inner lining fluorine pipe and is abutted against the outer wall of the inner lining fluorine pipe to form an inclined part positioned in the groove part.

According to the arrangement, the neck of the tank body can be lined through the lining fluorine pipe, and the lining fluorine pipe and the fluorine plate are bonded through the welding block in a melting mode, so that the effect of sealing between the lining fluorine pipe and the fluorine plate is achieved, the joint of the neck of the tank body is sealed through the structure, the phenomenon that liquid in the storage tank permeates from the joint of the neck to cause corrosion of the tank body and metal ion pollution to wet chemicals is avoided, and the purity of the stored wet chemicals can be guaranteed; and through setting up the slot part, in order to realize that the fluorine board is close to the one end of inside lining fluorine pipe upwards to contract to the slot part in, under the setting of this structure, be relative setting between rake and the inside lining fluorine pipe, the welding block that lies in under this kind of structure between the two can have an extrusion force to the rake, ensure that the rake can be better laminating on jar body surface, in order to realize that the rake is difficult to drop, and rake and inside lining fluorine pipe are to the reaction force part mutual offset on the welding block, and will play the effect of centre gripping to the welding block both sides, ensure that the welding block is difficult to drop more.

Further, the welding block comprises a main body portion, the fluorine lining pipe comprises a protruding portion protruding out of the inclined portion, the main body portion is connected with the fluorine plate and the protruding portion in a sealing mode, and the bottom of the main body portion is of a conical surface structure. The main body part performs annular welding sealing on the bulge part and the fluorine lining pipe so as to ensure that the joint has a better sealing effect; and the inclined structure of the bottom end of the main body part can realize the function of guiding the liquid attached above the main body part, namely the liquid attached to the bottom of the main body part flows downwards along the bottom of the main body part and is separated from the main body part, so that the liquid is prevented from staying on the main body part for a long time and permeating the main body part.

Further, the welding block further comprises an inflow part which is connected with the inclined part of the fluorine plate and the fluorine lining pipe main body in a sealing mode; the inflow part and the main body part are integrally formed and are arranged on the outer side of the fluorine lining pipe in a surrounding mode.

The gap between the fluorine plate inclined part and the inner lining fluorine pipe can be further filled by arranging the inflow part, so that the contact area between the welding block and the inner lining fluorine pipe and between the welding block and the fluorine plate is increased, and the sealing effect between the fluorine plate and the inner lining fluorine pipe can be further improved.

Further, an exhaust channel for exhausting air in the inflow part is arranged between the outer wall of the inner lining fluorine pipe and the inner wall of the neck part. When the welding block is melted and flows into a gap between the inclined part of the fluorine plate and the fluorine lining pipe, air at the gap can be discharged from the exhaust channel, so that the welding block can fully fill the gap between the inclined part and the fluorine lining pipe, and a larger contact area between the inflow part and the fluorine lining pipe and the fluorine plate is ensured; meanwhile, the phenomenon that air enters the interior of the molten welding rod when the welding rod is welded to cause a large amount of bubbles in the formed welding block can be avoided.

Further, the included angle of the joint of the neck and the tank body is R ₁ ，R ₁ R is more than or equal to 90 degrees ₁ Not more than 130 degrees, and the included angle of the cross section of the bottom end of the welding block is R ₂ . The can body and the neck can be vertical or inclined.

Further, R ₁ R is more than or equal to 110 degrees ₁ The roughness Ra of the contact part of the fluorine lining pipe and the fluorine plate with the inflow part is less than or equal to 130 degrees and less than 6.3. This kind of setting is because when the jar main part top was in the state of slope, the gap between rake and the inside lining fluorine pipe was narrower, can make this contact site smooth setting to it is less to realize the flow resistance of melting welding piece, thereby the gap between the inflow rake and the inside lining fluorine pipe that melting welding piece can be better, in order to realize better filling abundant to this gap, improve the sealing area of inflow portion, in order to realize that the junction can have a better sealed effect.

Further, inside lining fluorine pipe includes ear and the pipe portion of mutual fixed connection, the neck that the jar body was run through to the pipe portion, the ear is put in the outside of neck. By arranging the ear parts, the acting force can be concentrated on the ear parts when the neck part is connected with external structures such as a pipeline, and the situation that the pipeline moves along the neck part to cause the falling of the pipeline part and the like due to the concentrated acting force on the pipeline part during connection is avoided; the expanded ear part can realize that the inner lining fluorine pipe can have a larger contact surface with the connecting part when the neck part is connected with structures such as a pipeline and the like so as to ensure that the connecting part has a better sealing effect; the ear is put outside the neck, can also play the effect of blocking to the gap between pipe portion and the neck, avoids having the foreign matter to get into in the gap between pipe portion and the neck simultaneously.

Furthermore, a groove for placing a sealing ring is formed on the upper surface of the ear part of the fluorine pipe lined with the lining; or the upper surface of the ear part of the fluorine-lined pipe is a plane for placing a sealing gasket.

So set up, can be when the structure connection of outside such as neck and pipeline, the ear is through placing the sealing washer in the recess, or place at the planar seal gasket of ear's upper surface, can realize that ear and external connection structure are connected with better leakproofness.

Further, the width of the ear part of the fluorine lining pipe is X ₂ Inner diameter X of neck of tank body ₁ In a relationship of X ₂ /X ₁ ≥0.5。

So set up, can realize that the ear can have a sufficient area to the ear can play better sealing performance when guaranteeing to connect.

Further, the outer side of the bottom wall of the fluorine lining pipe is wrapped by the welding block. The arrangement can realize better connection between the welding block and the fluorine pipe in the lining, and is not easy to have gaps.

Drawings

To illustrate the technical solutions of the embodiments of the present invention more clearly, the drawings of the embodiments will be briefly described below, and it is obvious that the drawings in the following description only relate to some embodiments of the present invention, and are not intended to limit the present invention.

Fig. 1 is a schematic overall structure diagram of a first embodiment of the present invention;

fig. 2 is a schematic view of a structure around a neck according to an embodiment of the present invention;

FIG. 3 is a schematic view of a connection structure between the neck and the external structure when a groove is formed in the middle ear according to an embodiment of the present invention;

fig. 4 is a schematic structural view of a middle ear tip of the embodiment of the present invention having a planar structure and being sealed by a sealing gasket when being connected to an external structure;

fig. 5 is a schematic view of the structure around the neck in the second embodiment of the present invention;

fig. 6 is a schematic structural view of a joint between a welding block and a fluorine pipe lining in the third embodiment of the present invention.

Reference numerals:

1. a tank body; 11. a can body; 12. a neck portion; 2. a fluorine plate; 3. lining a fluorine pipe; 31. a projection; 32. an ear portion; 33. a tube portion; 4. welding the blocks; 41. a main body portion; 42. an inflow section; 5. a groove part; 6. an inclined portion; 7. an exhaust passage; 8. a groove; 9. a gasket seal.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the present invention will be described in further detail with reference to the accompanying drawings. The components of embodiments of the present invention, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts all belong to the protection scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

Unless defined otherwise, technical or scientific terms used herein shall have the ordinary meaning as understood by those of ordinary skill in the art to which the invention belongs. The use of "first," "second," and similar terms in the description and in the claims does not indicate any order, quantity, or importance, but rather is used to distinguish one element from another. Also, the use of the terms "a," "an," or "the" and similar referents do not denote a limitation of quantity, but rather denote the presence of at least one. The word "comprise" or "comprises", and the like, means that the element or item listed before "comprises" or "comprising" covers the element or item listed after "comprising" or "comprises" and its equivalents, and does not exclude other elements or items. "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like are used only to indicate relative positional relationships that may change when the absolute position of an object being described changes, and are merely for convenience in describing the invention and to simplify the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the invention.

Some embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The features in the embodiments described below may be combined with each other without conflict.

Example one

Referring to fig. 1, a corrosive chemical storage tank for holding or transporting corrosive wet chemicals including liquid substances such as sulfuric acid, soda ash and caustic soda solution.

Referring to fig. 1, the fluorine lining storage tank comprises a tank body 11 and a neck 12, wherein the tank body 11 and the neck 12 are vertically arranged, a fluorine plate 2 is adhered to the inner surface of the tank body 11 through an adhesive, the fluorine plate 2 is made of Polytetrafluoroethylene (PTFE), the neck 12 is provided with a lining fluorine pipe 3 penetrating through the neck 12, the lining fluorine pipe 3 extends into the tank body 11, and the lining fluorine pipe 3 is also made of PTFE.

Referring to fig. 2, to welding between fluorine board 2 and inside lining fluorine pipe 3 through the welding rod to form a welding 4 structure, and realize sealing between fluorine board 2 and the inside lining fluorine pipe 3 through welding 4, avoid the inside liquid of storage tank to permeate from the two junction, cause the corrosion of the jar body, and cause metal ion to pollute wet chemicals, thereby can guarantee the purity of the wet chemicals of storing.

The electrode described above is preferably a PFA electrode, and further, is preferably a PFA electrode having a diameter of 5 mm.

Referring to fig. 2, the tank body 1 is formed with a groove portion 5 at the junction of the tank main body 11 and the neck portion 12, and the end of the fluorine plate 2 close to the fluorine lining pipe 3 abuts against the outer wall of the fluorine lining pipe 3, so as to form an inclined portion 6 located in the groove portion 5, the inclined portion 6 is inclined upward along the groove portion 5, the inclined portion 6 of the fluorine plate 2 and the fluorine lining pipe are oppositely arranged, the included angle therebetween is less than 90 °, the welding block 4 located therebetween in this structure can have a pressing force on the inclined portion 6 and the fluorine lining pipe 3, the pressing force of the welding block 4 on the inclined portion 6 can ensure that the inclined portion 6 can better fit on the inner surface of the tank body 1, so that the inclined portion 6 is not easy to fall off, the reaction force of the inclined portion 6 and the fluorine lining pipe 3 on the welding block 4 partially offsets each other, and will play a role of clamping on both sides of the welding block 4, and ensure that the welding block 4 is not easy to fall off. And when the connecting end that slope 6 and interior lining fluorine pipe 3 are connected sets up for the level or slope downwards, the interior lining fluorine pipe 3 at this moment is not relative setting with slope 6 between, the opposite face of welding piece 4 and slope 6 junction is unsettled setting this moment, so welding piece 4 can't provide the extrusion force this moment, under slope 6 gravity and the action of gravity in the welding piece 4, the condition such as slope 6 and welding piece 4 come off appear easily and take place.

The structure can realize that one side of the fluorine plate 2 close to the inner lining fluorine pipe 3 is not easy to fall off downwards, and the structure is ensured to have better stability. And under the effect of welding piece 4, can further ensure that fluorine board 2 laminates on jar main part 11 inner wall, ensure that the structure of this junction can not appear breaking away from the circumstances such as, ensure that the structure has better stability and leakproofness all the time.

The welding rod is welded between the bulge part 31 of the bulge inclined part 6 of the lining fluorine pipe 3 and the fluorine plate 2 in the welding process, and is connected with the bulge part and the fluorine plate 2 in a sealing way to form a main body part 41 of the welding block 4.

And further, the welding rod can be melted and flowed into the gap between the inclined part 6 of the fluorine plate 2 and the main body of the fluorine-lined pipe 3 during welding, and the gap is filled to form the inflow part 42 of the welding block 4. The inflow portion 42 can increase the contact area between the solder bump 4 and the fluorine plate 2 and the fluorine-lined pipe 3, thereby improving the sealing performance.

Referring to fig. 2, the welding block 4, which is formed by the inflow portion 42 and the body portion 41 integrally formed, is entirely surrounded on the outside of the welding block 4, and seals the outer ring side of the fluorine-lined pipe 3 and the fluorine plate 2.

And after the welding block 4 is formed, the welding block 4 is trimmed by a tool so as to realize that the surface of the welding block 4, which is not in contact with the fluorine plate 2 of the inner lining fluorine pipe 3, is of a smooth structure, and preferably, the roughness Ra of the surface of the welding block 4 is less than or equal to 12.5, so that the surface of the welding block is in a more regular state, and better surface forming is realized.

The bottom of the main body 41 is a conical surface structure, and this arrangement can achieve the function of guiding the liquid attached above the main body, that is, the liquid attached to the bottom of the main body 41 will flow downwards along the bottom of the main body 41 to achieve the separation from the main body 41, so as to avoid the liquid from staying on the main body 41 for a long time and permeating into the main body 41.

Referring to fig. 2, the main body 41 may further include an included angle R ₂ The range is set to be more than or equal to R at 40 degrees ₂ Is less than or equal to 60 degrees, and the cross section refers to the cross section obtained by cutting the plane of the central axis of the fluorine lining pipe 3. This arrangement is because when the welding length of the welding block 4 to the fluorine-lined pipe 3 is fixed, an excessively small angle results in an excessively small contact area between the welding block 4 and the fluorine plate 2, resulting in poor sealing between the welding block 4 and the fluorine plate 2; and an excessive angle will result in an excessive contact area between the welding block 4 and the fluorine plate 2, and further lead to the waste of welding rods. Included angle R of cross section of welding block 4 ₂ When the angle of the welding rod is within the range, the welding block 4 can have enough contact area with the fluorine plate 2 and the inner lining fluorine pipe 3, so that the sealing effect is ensured, and meanwhile, the waste of welding rods is avoided.

The included angle between the fluorine plate 2 and the bottom surface of the main body part 41 can be set to be an obtuse angle, the included angle refers to the included angle of the section obtained by cutting the plane where the central axis of the fluorine lining pipe 3 is located, the included angle is the included angle of the part, not containing the main body part 41, of the bottom surface of the main body part 41 and the fluorine plate 2, and by means of the arrangement, when the included angle between the fluorine plate 2 and the bottom surface of the main body part 41 is an acute angle, liquid is easy to accumulate in the included angle, and the situation that the liquid penetrates through the welding block 4 and the like can occur for a long time.

Similarly, the included angle between the fluorine-lined pipe 3 and the bottom surface of the main body 41 can also be set to be an obtuse angle, so as to avoid liquid from accumulating in the gap between the fluorine-lined pipe 3 and the main body 41.

In the process that the welding rod is melted and flows into the gap between the inclined part 6 of the fluorine plate 2 and the main body of the fluorine lining pipe 3, air in the gap can hinder the welding rod from being melted in, and the air which can not be discharged can cause the condition that air bubbles exist in the welding block 4, and the like. Referring to fig. 2, an exhaust passage 7 may be provided between the outer wall of the fluorine-lined pipe 3 and the inner wall of the neck portion 12 to exhaust air in the gap between the inclined portion 6 of the fluorine plate 2 and the main body of the fluorine-lined pipe 3, so that the welding rod can flow into the gap better, and the molded inflow portion 42 can have a larger contact area with the fluorine-lined pipe 3 and the inclined portion 6 of the fluorine plate 2, thereby improving the sealing effect of the inflow portion 42. Meanwhile, the air bubbles in the formed welding block 4 can be reduced or the air bubbles in the formed welding block 4 are prevented from influencing the sealing performance of the welding block 4.

Neck 12 tip is provided with a plurality of through-holes to when realizing that structures such as external pipeline connect on neck 12, can connect through bolted construction, its integral connection presents flange structure or similar flange structure, and inside lining fluorine pipe 3 need be in the state of intercommunication with the inside of external structure such as external pipeline, and the junction of lining fluorine pipe 3 need keep sealed, appears the circulation when avoiding fluid transmission and leaks.

Based on this, can make inside lining fluorine pipe 3 include ear 32 and pipe portion 33, ear 32 and pipe portion 33 integrated into one piece set up to pipe portion 33 wherein runs through the neck 12 of jar main part 11, and ear 32 overlaps the outside at neck 12, and in order to realize connecting, the structure that expands outward that ear 32 appears can realize inside lining fluorine pipe 3's connection face bigger, in order to ensure that the junction can have better sealed effect, avoids the condition such as fluid from inside lining fluorine pipe 3 and external connection structure to go out to leak to take place. And the setting of ear 32 can realize when neck 12 is connected with the exterior structure, and the extrusion force of exterior structure to inside lining fluorine pipe 3 will concentrate on ear 32 to ear 32 can play the effect of support to inside lining fluorine pipe 3, takes place from the condition such as neck 12 drops easily when avoiding inside lining fluorine pipe 3 to be single straight tubular construction pressurized.

The width of the ear 32 of the fluorine-lined tube 3 is X ₂ Inner diameter X of neck 12 of can body 1 ₁ The relationship is X ₂ /X ₁ More than or equal to 0.5, so that the ear part 32 can have a sufficient area to ensure that the ear part 32 can have a good sealing performance when being connected.

Referring to fig. 3, the connecting surface of the ear portion 32 may be provided with a groove 8 for placing a sealing ring, so as to further improve the sealing performance of the connecting surface of the ear portion 32; or the connecting surface of the ear 32 is a plane structure, and a gasket is placed on the plane structure to improve the sealing performance of the ear 32 during connection through the gasket, and the structure is shown in fig. 4.

Example two

The difference from the first embodiment is that: referring to fig. 5, the angle between the neck 12 and the can body 11 is preferably R in order to ensure that the inclined part 6 of the fluorine plate 2 can penetrate into the groove 5, and the angle between the neck 12 and the can body 11 is preferably R ₁ > 90 deg., and the structure is further preferably R ₁ R is more than or equal to 110 degrees ₁ The structure of the tank body 1 is not more than 130 degrees, in the tank body 1 with the structure, the included angle between the inclined part 6 and the fluorine lining pipe 3 is smaller, so that on one hand, the inclined angle of the inclined part 6 of the fluorine plate 2 is larger, and the inclined part 6 of the fluorine plate 2 is not easy to fall off; on the other hand, however, this arrangement will make the angle of the gap between the inclined portion 6 and the fluorine-lined pipe 3 smaller, i.e., the solder bump 4 is more difficult to flow into this portion, and the contact area of the inflow portion 42 is smaller.

Can set up the lateral wall roughness of above-mentioned gap both sides as Ra < 6.3, this kind of setting can realize that the lateral wall of gap both sides is smooth setting to frictional resistance when reducing the melting welding rod and flowing, thereby can be more abundant when realizing the welding rod welding carry out abundant packing to this gap, it is bigger to ensure the area of contact after the shaping of inflow portion 42, in order to obtain higher sealing performance.

EXAMPLE III

The difference from the first embodiment or the second embodiment is that: referring to fig. 6, the welding block 4 wraps the outer side of the bottom wall of the fluorine lining pipe 3, for example, the outer edge of the bottom wall of the fluorine lining pipe 3, so as to further improve the connection performance between the welding block 4 and the fluorine lining pipe 3 and ensure that the joint is not easy to have a gap.

The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims (10)

1. A corrosive chemical storage tank, comprising:

a can body comprising a can body and a neck;

a fluorine plate bonded to an inner surface of the can body;

a fluorine-lined tube extending through the neck;

the welding block is welded with the fluorine plate and the fluorine lining pipe to form a seal;

the tank body is provided with a groove part at the joint of the tank main body and the neck part; the end, close to the inner lining fluorine pipe, of the fluorine plate is abutted against the outer wall of the inner lining fluorine pipe to form an inclined part positioned in the groove part.

2. The chemical storage tank of claim 1, wherein the welding block comprises a main body portion, the fluorine-lined pipe comprises a protrusion protruding out of the groove portion, the main body portion is connected with the fluorine plate and the protrusion in a sealing mode, and the bottom of the main body portion is of a conical surface structure.

3. The chemical storage tank of claim 2, wherein the weld block further comprises an inflow portion sealingly connected to the fluorine plate angled portion and the fluorine lined pipe body; the inflow part and the main body part are integrally formed, and the inflow part is arranged on the outer side of the fluorine lining pipe in a surrounding mode.

4. The chemical storage tank of claim 3 wherein a vent passage is provided between the outer wall of the fluorine-lined pipe and the inner wall of the neck to vent the inflow air.

5. A chemical storage tank as claimed in claim 3 or 4, wherein the neck is at an angle R to the tank body junction ₁ ，R ₁ R is more than or equal to 90 degrees ₁ ≤130°。

6. The chemical storage tank of claim 5 wherein R is ₁ R is more than or equal to 110 degrees ₁ The roughness Ra of the contact part of the fluorine lining pipe and the fluorine plate with the inflow part is less than or equal to 130 degrees and less than 6.3.

7. The chemical storage tank of claim 1 wherein said fluorine-lined pipe comprises an ear portion and a pipe portion fixedly connected to each other, said pipe portion extending through the neck portion of the tank body, said ear portion being disposed outside the neck portion.

8. The chemical storage tank of claim 7, wherein the upper surface of the ear of the inner lining fluorine pipe is provided with a groove for placing a sealing ring; or the upper surface of the ear part of the fluorine-lined pipe is a plane for placing a sealing gasket.

9. The chemical storage tank of claim 7, wherein the fluorine tube-lined ears have a width X ₂ Inner diameter X of neck of tank body ₁ The relationship is X ₂ /X ₁ ≥0.5。

10. The chemical storage tank of claim 1 wherein said fluorine lined pipe is wrapped around the outside of the bottom wall by a weld block.

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