Forced convection sandwich glass pre-presser

Abstract

The invention relates to a forced convection sandwich glass pre-presser. The forced convection sandwich glass pre-presser comprises an operation table, a preheating zone, an initial pressing zone, a convection zone, a final pressing zone, a sheet discharging zone, a pneumatic system, a forced convection system, a heat insulation system and a lifting device, wherein a plurality of groups of convection fans and a plurality of groups of high-temperature-resistant stainless steel air grids are arranged at the top and the bottom of a furnace body; each group of fans is mounted in a two-to-two correspondence manner; heating boxes are arranged at air inlets of the fans; the air grids are arranged at the lower parts of two heating boxes; air outlets are formed in the lower parts of the air grids and are aligned to to-be-processed glass; a plurality of thermocouples are mounted inside the furnace body; an upper furnace body is provided with an H-shaped linkage mechanism and a lifting mechanism; a motor on the side of the furnace body is used for driving the fans to generate forced convection for circularly transferring heat; motors of the fans adopt variable-frequency and variable-speed motors; a PLC processing system is used for controlling a frequency changer to automatically adjust the air volume in the furnace body; the strength of the upper convection is adjusted to be consistent with the heating of the lower surface, so that the to-be-processed glass is symmetrically and uniformly heated so as to be adaptive to requirements of different-radiation-rate LOW-E coated glass.

Description

technical field [0001] The invention relates to the field of glass machinery and equipment, in particular to a forced convection laminated glass pre-pressing machine. Background technique [0002] Laminated glass is usually used as safety glass in building wall curtains, squares, etc. It can also be used as bulletproof glass or other industrial applications. Laminated glass is a kind of PVB film sandwiched between two or more pieces of glass, and then heated and pressed to make them firmly bonded together. Usually the production process of laminated glass is as follows: firstly, after a preheating, that is, heating the PVB film in the glass to about 50°C, rolling once, and then heating again, that is, heating the PVB film to about 90°C, and then rolling again . At this time, the PVB film between the glasses is evenly distributed in the glass in a flocculent shape, and there is already a certain adhesion between the glasses. Finally, after a process of high temperature an...

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Problems solved by technology

[0003] The quartz tube conduction heating and medium-wave infrared radiation heating used in the traditional laminated glass production have the following disadvantages: the quartz tube contains quartz powder, and when the quartz tube breaks, the quartz powder will be mixed into the air, polluting the environment and harmful to the human body, not environmentally friendly ;The heating of quartz tube and medium wave tube will cause the local temperature in the furnace body to be too high, resulting in uneven temperature in the furnace body, which cannot process high-quality products, and it is difficult to control the heating of the heating tube by the program, so the power consumption is very high, and it is not energy-saving. , not efficient; medium-wave infrared radiation will affect the Low-E coated glass laminate, easily damage the Low-E coated surface, high scrap rate, and limited practical range; quartz tubes are easy to break, and the replacement time is long, which affects product processing Efficiency: It takes a long time for the infrared heating tube and the quartz heating tube to heat the laminated glass, and the running time of the laminated glass in the furnace is about 15 minutes and 20 minutes respectively; the working life of the medium-wave infrared heating tube is about 3000 hours, relatively short and expensive

Due to the extremely high reflectivity of the Low-E glass film surface, the radiation source must be very close to the glass in an ordinary radiant heating system, so that a large amount of heat will radiate to the edge of the glass, causing damage to the edge and corner of the glass. Overheating, causing instability and picture framing on the membrane surface, i.e. colored stress spots at the corners are common

Moreover, the uniform temperature is too high and the PVB film decomposes at high temperature. The traditional radiation heating furnace can no longer meet the requirements for Low-E glass. The development of a heating furnace suitable for processing Low-E glass is placed in front of all laminated glass manufacturers. urgent and daunting task

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