Large-tonnage one-kiln multi-line on-line TCO conductive glass production line

Abstract

The invention discloses a large-tonnage one-kiln multi-line on-line TCO conductive glass production line which comprises a kiln body provided with a feeding pool used for assisting in feeding, and further comprises heat supply assemblies arranged on the two sides of the kiln body and used for assisting in supplying heat to the interior of the kiln body. And a plurality of groups of line body assemblies for forming and processing the TCO conductive glass on line are arranged on the downstream of the kiln body. According to the large-tonnage one-kiln multi-line on-line TCO conductive glass production line, in the process of producing and processing TCO conductive glass by using a melting furnace structure, through mutual cooperation of the communication assemblies and the multiple sets of line body assemblies, forming processing of the multiple sets of TCO conductive glass can be conducted on line at the same time, and in the forming processing process, the production efficiency is improved, and the production cost is reduced. Through the operation of the edge roller in the tin bath on the multiple groups of wire body assemblies, the TCO conductive glass with different specifications and different shapes can be conveniently processed at the same time.

Description

Technical Field

[0001] The invention relates to the technical field of TCO conductive glass production, in particular to a large-tonnage one-kiln multi-line online TCO conductive glass production line. Background Art

[0002] TCO conductive glass is the most ideal electrode material for CdTe, CIGS and perovskite thin-film solar cells because of its dual functions of transparency and conductivity. There are three main types of TCO conductive glass, namely ITO, AZO and FTO glass. Among them, compared with offline coating technology, online TCO conductive glass can achieve low energy consumption, large-scale and high-quality production by using the fresh and clean surface of float glass and high temperature environment.

[0003] The existing online TCO conductive glass production lines are all traditional one-kiln-one-line structures, that is, on the basis of the traditional one-kiln-one-line ordinary / ultra-white float glass line, a CVD coating machine is added in the low-temperature area of ​​the tin bath. Due to the defect of the number of lines in the melting furnace structure of the production line, it is not convenient to simultaneously produce and process TCO conductive glass of different specifications online.

[0004] There is a certain relationship between the pulling capacity (tonnage) and pulling speed of the melting furnace and the thickness, width and narrowness of the glass. That is, when the pulling capacity is fixed, the faster the pulling speed, the thinner and narrower the glass product is, and vice versa. The thicker and wider it is. However, TCO glass requires thin glass as the original glass. At the same time, the online coating of the coating machine limits the width of the plate. Therefore, when the glass product is thin and narrow, the pulling capacity (tonnage) of the melting furnace is limited, which makes the energy consumption high.

[0005] The larger the melting furnace tonnage, the lower the energy consumption. Therefore, a large-tonnage one-furnace multi-line online TCO conductive glass production line is urgently needed to solve the above problems. Summary of the invention

[0006] The object of the present invention is to provide a large-tonnage one-kiln multi-line online TCO conductive glass production line to solve the problems raised in the above background technology.

[0007] To achieve the above-mentioned object, the present invention provides the following technical solutions: a large-tonnage one-kiln multi-line online TCO conductive glass production line, comprising a kiln body, a feeding pool for auxiliary material feeding is arranged upstream of the kiln body, and also comprises heating components arranged on both sides of the kiln body for assisting heating inside the kiln body, and a plurality of groups of line components for online TCO conductive glass forming processing are arranged downstream of the kiln body;

[0008] The line body component includes a branch line cooling part and a tin bath, the tin bath and the branch line cooling part are connected via a flow channel, the branch line cooling part and the kiln body are connected via a connecting component, a coating machine for online TCO conductive glass coating treatment after molding is provided on one side of the tin bath, a partition baffle for blocking the flowing glass liquid is provided on the flow channel, a lifting component for lifting the partition baffle and a separation component for scraping and separating the glass liquid adhered to the surface of the partition baffle during the lifting process are provided on the flow channel.

[0009] The connecting component comprises a main passage arranged downstream of the kiln body, the main passage is connected to the kiln body through a clamp, and one end of the branch cooling part on each group of the line body components is connected to the main passage.

[0010] The lifting assembly includes a U-shaped frame fixed to the upper end of the branch line cooling part, a guide assembly for guiding the partition baffle during the lifting process is arranged between the U-shaped frame and the partition baffle, a threaded tube is rotatably connected to the U-shaped frame, a threaded rod is threadedly engaged with the threaded tube, one end of the threaded rod is fixed to the partition baffle, and a driving motor for driving the threaded tube is installed on the U-shaped frame.

[0011] The guide assembly includes two groups of first sleeves fixed on the U-shaped frame, the two groups of first sleeves are symmetrically arranged on both sides of the threaded tube, the first sleeves are slidably connected with a first sliding rod, and one end of the first sliding rod is fixed to the partition baffle.

[0012] The separation component includes a mounting frame fixed on a U-shaped frame, a scraper is arranged on one side of the mounting frame, an elastic component for pressing the scraper against each other is arranged between the scraper and the mounting frame, and the scraper is kept against the outer side of the partition baffle under the elastic force of the elastic component.

[0013] The elastic component includes multiple groups of second sleeves fixed on the mounting frame, the second sleeves are slidably connected with a second slide bar, one end of the second slide bar is fixed to the scraper, and a spring is sleeved on the outer side of the second sleeve, and the two ends of the spring are respectively set to resist the mounting frame and the scraper.

[0014] The heat supply assembly comprises heat storage chambers arranged on both sides of the kiln body, and a small furnace is connected between the heat storage chambers and the kiln body.

[0015] Preferably, 2 to 6 branch cooling parts are provided, the center line of each branch cooling part is perpendicular to the center line of the main passage, and the center line spacing of each branch cooling part is 5 to 30 m.

[0016] Preferably, the length of the branch cooling part varies along the flow path of the molten glass in the main passage, and the distance from the neck outlet to each outlet of the branch cooling part is of different lengths, ranging from 10 to 40 m.

[0017] Preferably, the center line spacing of each branch cooling part is also different; each branch cooling part coincides with the center line of the flow channel and the tin bath; the coating machine is arranged in the low temperature zone of the tin bath, and each coating machine can be arranged on the left side of the tin bath or on the right side of the tin bath, on different sides or on the same side; the pool walls of the main passage and each branch cooling part are provided with an insulation layer, and the material is the same, and the thickness of the insulation layer provided on the outermost side of the main passage and the outermost pool walls of the branch cooling parts at both ends is 1.1 to 2 times the thickness of the insulation layer of other pool walls.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. The daily pulling capacity of the TCO conductive glass production line of the present invention is 1000 to 2400 tons, and the number of small furnaces M is 6 to 13 pairs, which realizes the online production of TCO conductive glass by a large-tonnage melting furnace (pulling capacity ≥ 1000 tons / day), effectively reducing the production energy consumption of TCO conductive glass.

[0020] 2. The production line of the present invention arranges N branch cooling sections on one side of the passageway away from the main body of the melting furnace. The branch cooling sections are set to be of unequal width or equal width, and can produce two-part or three-part panels according to production needs. The pulling amount of the branch cooling section is set to be non-evenly distributed, which can achieve stable production of TCO conductive glass of different thicknesses produced by different branches without reducing the total pulling amount of the melting furnace, solving the problem that the traditional one-kiln-one-line online TCO glass production line can only produce a single glass specification product at a time, and the problem of labor time loss and product loss caused by glass thickness and film layer adjustment, which greatly improves the process stability.

[0021] 3. The melting furnace and production line of the present invention have simple structures, and the glass liquid heat balance of each branch cooling part is good. The branch line arrangement is conducive to the process operation of the bottleneck and coating unit.

[0022] 4. The present invention retains the cooling section of one kiln and one line, eliminating the influence of diversion on the melting and clarification quality, so that the glass liquid can be fully heat homogenized after melting and clarification. After the neck is clamped, the glass liquid flows more smoothly, and the glass liquid only undergoes a large-scale turn once, which can greatly reduce the turbulence and the scouring of refractory materials. These advantages can make the melting, clarification, homogenization and optical quality of the glass liquid more guaranteed. The intrinsic, optical quality and mechanical strength of the finished TCO conductive glass are better than other design methods.

[0023] 5. The present invention sets the distance from the outlet of the neck to the outlet of the cooling part of each branch line to unequal lengths according to the different degrees of temperature drop of each branch line. This method can better ensure the thermal balance between the various passages. The different spacings between the branches can make the replacement and maintenance space of the coating machine more compact, reduce the stroke length of the glass liquid after the neck, and reduce the heat dissipation of the glass liquid, thereby achieving energy-saving production. A large-tonnage one-kiln multi-line online TCO conductive glass production line of the present invention uses a melting furnace structure to produce and process TCO conductive glass. Through the mutual cooperation of the connecting components and the multiple groups of wire body components, multiple groups of TCO conductive glass can be formed at the same time. In the process of forming and processing, through the operation of the internal drawing machine of the tin bath on the multiple groups of wire body components, it is convenient to simultaneously process TCO conductive glass of different specifications and different shapes.

[0024] 6. The design of one furnace with multiple lines can not only meet the requirements of thin glass production with small tonnage and narrow width of each branch line, but also achieve large tonnage and low energy consumption production of the melting furnace. This solves the problem of small tonnage and high energy consumption of the current TCO glass production line.

[0025] In general, the large-tonnage one-kiln multi-line online TCO conductive glass production line of the present invention uses a melting furnace structure to produce and process TCO conductive glass. Through the cooperation of the connecting components and the multiple groups of wire body components, multiple groups of TCO conductive glass can be formed at the same time. In the process of forming, the operation of the internal edge drawing machine of the tin bath on the multiple groups of wire body components facilitates the simultaneous processing of TCO conductive glass of different specifications and different shapes. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall appearance structure of the present invention;

[0027] Figure 2 It is a schematic diagram of the branch cooling part and the partition baffle structure of the present invention;

[0028] Figure 3 It is a schematic diagram of the structure of the lifting assembly and the guide assembly of the present invention;

[0029] Figure 4 It is a schematic diagram of the structure of the elastic component and the separation component of the present invention;

[0030] Figure 5 It is a three-dimensional diagram of the flow channel structure of the present invention;

[0031] Figure 6 It is a plan view of the flow channel structure of the present invention.

[0032] In the figure: 101, kiln body; 102, feeding tank; 201, heat storage chamber; 202, small furnace; 301, branch cooling section; 302, tin bath; 303, flow channel; 304, coating machine; 401, main passage; 402, neck; 501, U-shaped frame; 502, threaded pipe; 503, threaded rod; 504, driving motor; 601, first sleeve; 602, first slide bar; 701, mounting frame; 702, scraper; 801, second sleeve; 802, second slide bar; 803, spring; 9, partition baffle. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] See also Figure 1-6 The present invention provides a large-tonnage one-kiln multi-line online TCO conductive glass production line, comprising a kiln body 101, a feeding pool 102 for auxiliary material feeding is arranged upstream of the kiln body 101, and also includes heating components arranged on both sides of the kiln body 101 for assisting heating inside the kiln body 101, and multiple groups of line components for online TCO conductive glass forming processing are arranged downstream of the kiln body 101;

[0035] The line assembly includes a branch cooling portion 301, a flow channel 303 and a tin bath 302;

[0036] It is worth noting that: the inside of the tin bath 302 is provided with a side drawing machine for assisting the glass liquid in forming, wherein the side drawing machine is a conventional technical means in the process of forming the conductive glass, and is regarded as the prior art in this application, and will not be described in detail here;

[0037] The tin tank 302 is connected to the branch cooling part 301 through the flow channel 303, and the branch cooling part 301 is connected to the kiln body 101 through the connecting component. A coating machine 304 for online TCO conductive glass coating after forming is arranged on one side of the tin tank 302. A partition baffle 9 for blocking the flowing glass liquid is arranged on the flow channel 303. A lifting component for lifting the partition baffle 9 and a separation component for scraping and separating the glass liquid adhered to the surface of the partition baffle 9 during the lifting process are arranged on the flow channel 303.

[0038] It should be noted here that: in the process of producing and processing TCO conductive glass using a melting furnace structure, through the cooperation between the connecting components and the multiple groups of wire components, multiple groups of TCO conductive glass can be formed and processed at the same time, and in the process of forming and processing, through the operation of the internal edge drawing machine of the tin bath 302 on the multiple groups of wire components, TCO conductive glass of different specifications and shapes can be processed simultaneously.

[0039] The connecting component includes a main passage 401 arranged downstream of the kiln body 101, the main passage 401 and the kiln body 101 are connected through a clamp 402, and one end of the branch cooling part 301 on each group of line body components is connected to the main passage 401;

[0040] It should be noted here that: during the production and processing of TCO conductive glass using a melting furnace structure, the glass liquid generated after the kiln body 101 is heated and melted is transported toward the branch cooling part 301 of each group of line body components through the connecting and guiding function of the neck 402 and the main passage 401.

[0041] The lifting assembly includes a U-shaped frame 501 fixed to the upper end of the branch cooling section 301, a guide assembly for guiding the partition baffle 9 during the lifting process is arranged between the U-shaped frame 501 and the partition baffle 9, a threaded tube 502 is rotatably connected to the U-shaped frame 501, a threaded rod 503 is threadedly engaged with the threaded tube 502, one end of the threaded rod 503 is fixed to the partition baffle 9, and a driving motor 504 for driving the threaded tube 502 is installed on the U-shaped frame 501;

[0042] It should be noted here that: the threaded tube 502 is driven to rotate by the driving motor 504. During the rotation of the threaded tube 502, the partition baffle 9 is lifted and lowered by the mutual meshing transmission between the threaded tube 502 and the threaded rod 503 and the guiding effect of the guide assembly.

[0043] The guide assembly includes two groups of first sleeves 601 fixed on the U-shaped frame 501, the two groups of first sleeves 601 are symmetrically arranged on both sides of the threaded tube 502, and the first sleeves 601 are slidably connected with a first slide bar 602, one end of the first slide bar 602 is fixed to the partition baffle 9;

[0044] It should be noted here that: the partition baffle 9 is guided during the lifting process by multiple sets of first sleeves 601 and first slide bars 602.

[0045] The separation assembly includes a mounting frame 701 fixed on the U-shaped frame 501, a scraper 702 is arranged on one side of the mounting frame 701, and an elastic component for pressing the scraper 702 against the mounting frame 701 is arranged between the scraper 702 and the mounting frame 701, and the scraper 702 is kept against the outer side of the partition baffle 9 under the elastic force of the elastic component;

[0046] It should be noted here that: when it is necessary to restart the operation of the line body assembly after being paused, the partition baffle 9 is driven by the lifting assembly and the guide assembly to no longer be in a state of abutting against the branch line cooling part 301. During the upward movement of the partition baffle 9, the scraper 702 is kept against the outer side of the partition baffle 9 under the elastic force of the elastic assembly, and the glass liquid adhered to the surface of the partition baffle 9 after the partition is used is scraped and separated, so as to avoid the drying of the glass liquid adhered to the partition baffle 9 and affect the subsequent use of the partition baffle 9 for isolation.

[0047] The elastic component includes a plurality of second sleeves 801 fixed on the mounting frame 701, a second slide bar 802 is slidably connected to the second sleeve 801, one end of the second slide bar 802 is fixed to the scraper 702, a spring 803 is sleeved on the outer side of the second sleeve 801, and both ends of the spring 803 are respectively set against the mounting frame 701 and the scraper 702;

[0048] It should be noted here that: through multiple sets of second sleeves 801 and second slide bars 802, the scraper 702 is assisted to stably extend and retract after being stressed, and through the action of the spring 803, the scraper 702 is pushed to maintain contact with the outer side of the partition baffle 9.

[0049] The heating assembly includes a heat storage chamber 201 disposed on both sides of the kiln body 101, and a small furnace 202 is connected between the heat storage chamber 201 and the kiln body 101;

[0050] It should be noted that the function of the regenerator 201 is heat exchange: the high temperature flue gas of the melting furnace heats the regenerator lattice body, and the regenerator completes heat storage; the combustion air absorbs the heat of the regenerator lattice body and heats up, and the regenerator completes heat release. The external fuel meets the high temperature combustion air in the small furnace 202 and burns, providing heat to the inside of the kiln body 101.

[0051] There are 2 to 6 branch cooling parts 301 , and the center line of each branch cooling part 301 is perpendicular to the center line of the main passage 401 . The center line spacing of each branch cooling part 301 is 5 to 30 m.

[0052] The length of the branch cooling part 301 varies along the flow path of the glass liquid in the main passage 401 , and the distance from the outlet of the neck 402 to the outlet of each branch cooling part 301 is of different lengths, ranging from 10 to 40 m.

[0053] The center line spacing of each branch cooling part 301 is also different; each branch cooling part 301 coincides with the center line of the flow channel 303 and the tin bath 302; the coating machine 304 is arranged in the low temperature zone of the tin bath 302, and each coating machine 304 can be arranged on the left side of the tin bath 302 or on the right side of the tin bath 302, and can be on the different sides or the same side.

[0054] The pool walls of the main passage 401 and each branch cooling part 301 are both provided with an insulation layer, and the material is the same. The thickness of the insulation layer provided on the outermost side of the main passage 401 and the outermost side of the branch cooling parts 301 at both ends is 1.1 to 2 times the thickness of the insulation layer of other pool walls.

[0055] Working principle: In the process of producing and processing TCO conductive glass using a melting furnace structure, the glass liquid generated after the glass batch material inside the kiln body 101 is heated and melted is transported toward the branch cooling part 301 of each group of line body components through the connecting and guiding effect of the clamp neck 402 and the main passage 401. After being transported to the inside of the branch cooling part 301, the glass liquid passes through the flow channel 303 and is circulated and transported to the inside of the tin bath 302. Through the action of the edge drawing machine inside the tin bath 302, the forming operation of the TCO conductive glass is assisted. In the low temperature area of ​​the tin bath 302, the coating machine 304 is used to perform online coating to form a TCO conductive glass product to enter the subsequent process. In the process of forming the TCO conductive glass, through the mutual cooperation of the connecting component and the multiple groups of line body components, the forming processing of multiple groups of TCO conductive glasses can be carried out at the same time. In the process of forming, through the operation of the edge drawing machine inside the tin bath 302 on the multiple groups of line body components, it is convenient to process TCO conductive glasses of different specifications and shapes online at the same time.

[0056] When it is necessary to interrupt a certain line component and stop the forming process, the lifting component and the guide component cooperate with each other to drive the partition baffle 9 to descend and collide with the branch cooling part 301, thereby blocking the flow of glass liquid on the line component, thereby realizing flexible switching of operations and suspension operations of different line components;

[0057] When it is necessary to restart the operation of the line body component after being paused, the partition baffle 9 is driven by the lifting assembly and the guide assembly to no longer be in a state of abutting against the branch line cooling part 301. During the upward movement of the partition baffle 9, the scraper 702 is kept against the outer side of the partition baffle 9 under the elastic force of the elastic assembly, and the glass liquid adhered to the surface of the partition baffle 9 after the partition is used is scraped and separated, so as to prevent the glass liquid adhered to the partition baffle 9 from drying up and affecting the subsequent use of the partition baffle 9 for partitioning.

[0058] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A large-tonnage one-kiln multi-line online TCO conductive glass production line, comprising: A kiln body (101), wherein a feeding pool (102) for auxiliary material feeding is arranged upstream of the kiln body (101); It is characterized by further comprising: Heat supply components are arranged on both sides of the kiln body (101) for assisting in supplying heat to the inside of the kiln body (101); a plurality of line components for online TCO conductive glass forming processing are arranged downstream of the kiln body (101); The line body component comprises a branch cooling part (301) and a tin bath (302); the tin bath (302) and the branch cooling part (301) are connected via a flow channel (303); the branch cooling part (301) and the kiln body (101) are connected via a connecting component; a coating machine (304) for online TCO conductive glass coating treatment after forming is arranged on one side of the low temperature zone of the tin bath (302); a blocking plate (9) for blocking the flowing glass liquid is arranged on the flow channel (303); a lifting component for lifting the blocking plate (9) and a separation component for scraping and separating the glass liquid adhered to the surface of the blocking plate (9) during the lifting process are arranged on the flow channel (303).

2. The large-tonnage one-kiln multi-line online TCO conductive glass production line according to claim 1 is characterized by: The connecting component comprises a main passage (401) arranged downstream of the kiln body (101), the main passage (401) and the kiln body (101) are connected via a neck (402), and one end of the branch cooling part (301) on each group of the line body components is connected to the main passage (401).

3. The large-tonnage one-kiln multi-line online TCO conductive glass production line according to claim 1 is characterized by: The lifting assembly comprises a U-shaped frame (501) fixed to the upper end of the branch cooling section (301); a guide assembly for guiding the partition baffle (9) during the lifting process is arranged between the U-shaped frame (501) and the partition baffle (9); a threaded tube (502) is rotatably connected to the U-shaped frame (501); a threaded rod (503) is threadedly engaged with the threaded tube (502); one end of the threaded rod (503) is fixed to the partition baffle (9); and a driving motor (504) for driving the threaded tube (502) is installed on the U-shaped frame (501).

4. The large-tonnage one-kiln multi-line online TCO conductive glass production line according to claim 3 is characterized by: The guide assembly comprises two groups of first sleeves (601) fixed on the U-shaped frame (501), the two groups of first sleeves (601) are symmetrically arranged on both sides of the threaded tube (502), and a first sliding rod (602) is slidably connected to the first sleeve (601), and one end of the first sliding rod (602) is fixed to the partition baffle (9).

5. The large-tonnage one-kiln multi-line online TCO conductive glass production line according to claim 3 is characterized by: The separation component comprises a mounting frame (701) fixed on a U-shaped frame (501); a scraper (702) is arranged on one side of the mounting frame (701); an elastic component for pressing the scraper (702) against each other is arranged between the scraper (702) and the mounting frame (701); and the scraper (702) is kept against the outer side of the partition baffle (9) under the elastic pressure of the elastic component.

6. The large-tonnage one-kiln multi-line online TCO conductive glass production line according to claim 5 is characterized by: The elastic component comprises a plurality of groups of second sleeves (801) fixed on the mounting frame (701), a second slide bar (802) being slidably connected to the second sleeve (801), one end of the second slide bar (802) being fixed to the scraper (702), a spring (803) being sleeved on the outer side of the second sleeve (801), and two ends of the spring (803) being respectively disposed against the mounting frame (701) and the scraper (702).

7. The large-tonnage one-kiln multi-line online TCO conductive glass production line according to claim 1 is characterized by: The heat supply assembly comprises heat storage chambers (201) arranged on both sides of the kiln body (101), and a small furnace (202) is connected between the heat storage chambers (201) and the kiln body (101).

8. The large-tonnage one-kiln multi-line online TCO conductive glass production line according to claim 1, characterized in that: The branch cooling sections (301) are provided in 2 to 6 numbers, the center line of each branch cooling section (301) is perpendicular to the center line of the main passage (401), and the center line spacing of each branch cooling section (301) is 5 to 30 m.

9. The large-tonnage one-kiln multi-line online TCO conductive glass production line according to claim 1, characterized in that: The length of the branch cooling section (301) varies along the flow path of the glass liquid in the main passage (401), and the distance from the outlet of the neck (402) to the outlet of each branch cooling section (301) is of different lengths, ranging from 10 to 40 m.

10. The large-tonnage one-kiln multi-line online TCO conductive glass production line according to claim 1, characterized in that: The center line spacing of each branch cooling part (301) is also different; each branch cooling part (301) coincides with the center line of the flow channel (303) and the tin bath (302); the coating machine (304) is arranged in the low temperature zone of the tin bath (302), and each coating machine (304) can be arranged on the left side of the tin bath (302) or on the right side of the tin bath (302), and can be on different sides or on the same side; the pool wall of the main passage (401) and each branch cooling part (301) are provided with an insulation layer, and the material is the same, and the thickness of the insulation layer provided on the outermost pool wall of the main passage (401) and the branch cooling parts (301) located at both ends is 1.1 to 2 times the thickness of the insulation layer of other pool walls.

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