阅读说明：本技术 一种平板玻璃热弯加工的方法 (Method for hot bending plate glass ) 是由 刘永生 黄勇祥 郑建万 支金梁 傅志敏 于 2021-03-09 设计创作，主要内容包括：本发明公开了一种平板玻璃热弯加工的方法,先将平板玻璃清洗去除杂质和油污,固定在治具中,使玻璃弯曲成预定的形状；然后对治具及玻璃进行预热处理,再将其放入钢化盐浴中进行钢化处理,钢化处理的同时进行完成热弯定型；最后对治具及玻璃进行退火处理,完成平板玻璃的热弯及钢化加工。常规的热弯是单独的一道工序,需要将玻璃加热到软化点,再将玻璃形成既定形状。本发明在对玻璃进行钢化作业时完成热弯加工,提高了生产效率和热能利用率,降低了能源消耗。(The invention discloses a method for hot bending plate glass, which comprises the steps of cleaning plate glass to remove impurities and oil stains, fixing the plate glass in a jig, and bending the glass into a preset shape; then, preheating the jig and the glass, and then putting the jig and the glass into a toughening salt bath for toughening treatment, wherein the toughening treatment is carried out while the hot bending and shaping are completed; and finally, annealing the jig and the glass to finish the hot bending and tempering of the flat glass. Conventional hot bending is a single process step that requires heating the glass to a softening point and then forming the glass into a desired shape. The invention finishes the hot bending processing when the glass is toughened, improves the production efficiency and the heat energy utilization rate and reduces the energy consumption.)

1. A method for hot bending plate glass is characterized by comprising the following steps:

s1, cleaning the flat glass to remove impurities and oil stains, and fixing the flat glass in a jig to bend the glass into a preset shape;

s2, preheating the jig and the glass, then putting the jig and the glass into a toughening salt bath for toughening, and finishing hot bending and shaping while toughening;

and S3, annealing the jig and the glass to finish the hot bending and tempering of the flat glass.

2. The method of claim 1, wherein: the thickness of the flat glass in the S1 is 0.2-1.8 mm; the preset bending angle is 3-40 degrees.

3. The method of claim 2, wherein: the preheating temperature in the S2 is 350-420 ℃, and the time is 1-3 h.

4. The method of claim 1, wherein: in S2, the toughening temperature is 380-450 ℃, and the time is 1-8 ℃; the toughening salt bath is a molten salt bath of potassium ions.

5. The method of claim 1, wherein: and in the annealing treatment in the S3, the temperature is 250-400 ℃, and the time is 0-60 minutes.

6. The method according to claims 1 to 5, wherein: the jig is of a frame structure and made of aluminum alloy, clamping grooves for fixing two ends of glass are formed in two sides of the jig, and the clamping grooves are vertically formed; a plurality of groups of clamping groove structures are repeatedly arranged in one set of jig.

7. The method of claim 6, wherein: the opening distance of the clamping grooves in the jig is 5-15mm, and the distance between two adjacent groups of clamping grooves is controlled to be 20-35 mm.

Technical Field

The invention relates to the technical field of glass preparation, in particular to a method for hot bending processing of plate glass.

Background

The existing conventional glass hot bending process needs to heat glass to a higher temperature to soften the glass, then utilizes the self gravity of the glass or a hot bending jig to apply external force to enable the glass to reach a pre-designed appearance, and the formed hot bent glass is slowly cooled to release residual stress so as to enable the glass to become stable curved glass. The hot bending process is an independent process, and the conventional product is often subjected to tempering later. The softening temperature of the glass is about 600 ℃, the existing hot bending is generally heated to the temperature for hot bending processing, and the time from glass preheating to hot bending processing to glass annealing is generally more than 2.5 hours, so that the energy consumption is very large, and the heat energy utilization rate is very low; the production efficiency is low, the hot bending processing of a furnace of products is completed within 2.5 hours, and then the glass toughening processing is needed for 4-8 hours.

In addition, the bending processing of the glass is finished by adopting two times of toughening and one time of film coating, the toughening time of the two times is at least more than 8 hours, and in addition, one film coating procedure is added, so that two procedures are added in the product flow, the processing period is long, the production efficiency is low, and the product yield is also reduced. The curved glass processed and formed by the scheme is realized by the stress difference of two surfaces during the secondary tempering of the glass, the stress of the two surfaces has larger difference, certain performance of the strengthened glass is sacrificed, and the glass is easy to damage in the subsequent processing and using processes.

Disclosure of Invention

The invention provides a method for hot bending of plate glass, which is characterized in that the hot bending of the plate glass is completed when the plate glass is tempered, the plate glass is arranged in a fixed jig to form a preset bent shape, the plate glass is simultaneously bent when the plate glass is chemically tempered, and the bent shape is stabilized during the annealing process.

The technical scheme of the invention is that the method for hot bending the plate glass is characterized by comprising the following steps:

s1, cleaning the flat glass to remove impurities and oil stains, and fixing the flat glass in a jig to bend the glass into a preset shape;

s2, preheating the jig and the glass, then putting the jig and the glass into a toughening salt bath for toughening, and finishing hot bending and shaping while toughening;

and S3, annealing the jig and the glass to finish the hot bending and tempering of the flat glass.

Further, the thickness of the flat glass in the S1 is 0.2-1.8 mm; the preset bending angle is 3-40 degrees.

Further, the preheating temperature in the S2 is 350-420 ℃, and the time is 1-3 h.

Further, the toughening temperature in S2 is 380-450 ℃, and the time is 1-8 ℃; the toughening salt bath is a molten salt bath of potassium ions.

Further, in the annealing treatment in S3, the temperature is 250-400 ℃ and the time is 0-60 minutes.

Furthermore, the jig is of a frame structure and made of aluminum alloy, clamping grooves for fixing two ends of the glass are formed in two sides of the jig, and the clamping grooves are vertically formed; a plurality of groups of clamping groove structures are repeatedly arranged in one set of jig.

Furthermore, the opening distance of the clamping grooves in the jig is 5-15mm, and the distance between two adjacent groups of clamping grooves is controlled to be 20-35 mm.

The invention has the following beneficial effects:

compared with the traditional hot bending and tempering annealing process, the hot bending process can omit the hot bending step by adopting the jig, the jig is utilized to form a certain bending radian before tempering, tempering treatment is directly carried out, the tempering salt bath is utilized to achieve a certain shaping effect on the bent glass during tempering, the shaping effect after hot bending is further strengthened by annealing, and the hot bending and tempering processing treatment of the glass is completed. The invention integrates two very complicated and time-consuming procedures into one procedure to be completed, thereby not only meeting the toughening requirement of the product, but also achieving the effect of glass hot bending molding; meanwhile, the product processing flow is reduced, and the product yield is improved.

The method provided by the invention is particularly suitable for hot bending processing of a single bent shape, integrates two processes of hot bending and tempering into one process, and completes the processing of single hot bending of glass while tempering processing, compared with the traditional process, the method greatly optimizes the production flow and improves the production efficiency by at least 50%. Secondly, the glass toughening temperature is generally about 420 ℃, higher glass softening temperature is not required to be reached, secondary toughening is not required, and the energy consumption is reduced by at least 50%; and thirdly, the hot bending and the tempering are simultaneously carried out in the same hot furnace, so that the utilization rate of heat energy is improved. In addition, the strength of the front and the back of the product is consistent, no stress difference exists, and the product performance is ensured. And the hot bending processing of the glass is finished in the glass toughening procedure, only one toughening procedure is needed, and a coating layer is not needed.

Drawings

FIG. 1 is a plan view of a plate glass fixed in a jig according to example 1.

FIG. 2 is a top view of the glass after hot bending.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to examples, but those skilled in the art will appreciate that the following examples are only illustrative of the present invention and should not be construed as limiting the scope of the present invention.

When the glass is subjected to the hot bending treatment, the maximum bendable angle of the glass with different thicknesses is different, and the specific values are shown in the following table 1

Thickness of glass substrate

0.2～0.25mm

0.33～0.4mm

0.5～0.55mm

0.7mm

1.1mm

1.3mm

1.8mm

Maximum bendable angle

40°

35°

30°

15°

10°

5°

3°

TABLE 1

Example 1:

the thickness of the flat glass is 0.7mm, and the required bending angle is 10 degrees.

The specific treatment steps are as follows: firstly, plate glass is cleaned, particle impurities, oil stains and the like on the surface of the glass are removed, then the glass is fixed in a special jig, as shown in fig. 1, clamping grooves are designed on two sides of the jig, and the two sides of the glass are clamped in the clamping grooves on two sides of the jig, so that the glass is prevented from sliding and being scratched between front and rear glass products. The interval of draw-in groove 5mm, the distance control 20mm of adjacent two sets of draw-in grooves ensures that the tempering is abundant and the piece is unanimous with crooked between the piece.

The distance between the two sides of the jig is represented as D, the width of the glass is represented as L, the distance between the two sides of the jig is designed to be adjustable, and specifically, the distance between the two sides of the jig is adjusted to a required value through adjusting the distance fixing screws of the jig, and then the distance between the jigs is fixed through fastening screws. The size of D is adjusted to 437.2mm, and the glass is accurately controlled to reach a preset bending radian. By adjusting different values of D, the curvature of the glass can be continuously adjusted within a certain range, and different customer requirements can be met.

One set of tool designs multiunit repeating unit, can pack into 20 pieces of glass simultaneously, realizes once accomplishing 20 pieces of glass tempering and bending process. And a plurality of sets of jigs are repeatedly recycled, so that continuous production can be realized. After the glass is put into the jig, the glass of the jig is hoisted to a preheating furnace for preheating treatment, the treatment is carried out for 1h at 400 ℃, after the process treatment time is reached, the glass of the jig is soaked in a toughening salt furnace for toughening treatment, and simultaneously the glass is also subjected to hot bending treatment at the temperature of 440 ℃ for 4h, wherein the specific toughening salt bath is KNO₃And melting the molten liquid, after finishing tempering and hot bending, lifting the glass of the treatment tool out of the salt furnace, lifting the glass into an annealing furnace for annealing treatment at the temperature of 350 ℃ for 1h, releasing the internal stress of the glass, and finishing tempering and hot bending post-processing. The hot-bent shaped glass is shown in fig. 2.

Judging the product to be qualified when the bending angle is 10 +/-0.25 degrees according to the requirements of curved surface products; the stress of the toughened product is not less than 500MPa measured by an FSM-6000LE stress instrument. The obtained hot-bent glass meets the requirements.

Example 2:

the thickness of the flat glass is 0.7mm, and the required bending angle is 15 degrees.

S1, cleaning the flat glass to remove impurities and oil stains, fixing the flat glass in a jig, and bending the glass into a preset shape, wherein the width D of the jig is adjusted to be 429.7mm for a product with the glass width of 450mm as an example;

s2, preheating the jig and the glass at 400 ℃ for 1h, and then putting the jig and the glass into tempering KNO₃Carrying out toughening treatment in a molten salt bath, wherein the toughening treatment temperature is 440 ℃, and the time is 4 h; finishing hot bending and shaping while toughening;

and S3, annealing the jig and the glass at 350 ℃ for 1h to finish the hot bending and tempering of the plate glass.

Judging the product to be qualified when the bending angle is 15 +/-0.25 degrees according to the requirements of curved surface products; the stress of a toughened product is not less than 500MPa measured by an FSM-6000LE stress instrument; the obtained hot-bent glass meets the requirements.

Example 3:

the thickness of the flat glass is 0.25mm, and the required bending angle is 40 degrees.

S1, cleaning the flat glass to remove impurities and oil stains, fixing the flat glass in a jig to bend the glass into a preset shape, and adjusting the width D of the jig to be 317.4 mm;

s2, preheating the jig and the glass at 360 ℃ for 2h, and then putting the jig and the glass into tempering KNO₃Carrying out toughening treatment in a molten salt bath, wherein the toughening treatment temperature is 420 ℃, and the time is 2 hours; finishing hot bending and shaping while toughening;

and S3, annealing the jig and the glass at 390 ℃ for 45m to finish the hot bending and tempering of the plate glass.

Judging the product to be qualified when the bending angle is 40 +/-0.5 degrees according to the requirements of curved surface products; the hot bending glass obtained by measuring the stress of a toughened product by an FSM-6000LE stress instrument is equal to or larger than 550MPa and meets the requirements.

Example 4:

the thickness of the plate glass is 1.5mm, and the required bending angle is 3 degrees.

S1, cleaning the flat glass to remove impurities and oil stains, fixing the flat glass in a jig to bend the glass into a preset shape, and adjusting the width D of the jig to be 446.7 mm;

s2, preheating the jig and the glass at 390 ℃ for 1h, and then putting the jig and the glass into tempering KNO₃Carrying out toughening treatment in a molten salt bath, wherein the toughening treatment temperature is 450 ℃ and the toughening treatment time is 5 hours; finishing hot bending and shaping while toughening;

and S3, annealing the jig and the glass at 400 ℃ for 1h to finish the hot bending and tempering of the plate glass.

Judging the product to be qualified when the bending angle is 3 +/-0.1 degrees according to the requirements of curved surface products; the stress of a toughened product is not less than 500MPa measured by an FSM-6000LE stress instrument, and the obtained hot bent glass meets the requirements.

The invention integrates two very complicated and time-consuming procedures into one procedure to be completed, thereby not only meeting the toughening requirement of the product, but also achieving the effect of glass hot bending molding; meanwhile, the product processing flow is reduced, and the product yield is improved. The method meets the product requirements, greatly improves the production efficiency and reduces the energy consumption.