Round Tempered Glass for Light Cover Boiler Observation
Products |
tempered glass for LED lamps |
Raw materials |
ordinary transparent glass, ultra white transparent glass, high borosilicate glass. |
Processing thickness |
1-15mm |
Surface hardness |
greater than 6H |
Glass shapes can be customized |
strip, square, round, shaped. |
The edge can be processed |
light edge, fog edge, bevel edge. |
The surface can be treated |
etching, spraying, anti-fog |
Tempering method |
physical tempering |
Screen color |
Customizable |
Common types
about project1) Tempered screen glass
Such as silk screen black frame, attached number, pattern and LOGO, etc., you can also open holes, all toughened, to support the processing of various non-standard specifications and conventional sizes.
2) AG frosted glass
This kind of glass can be used for the AG panel of the lamp, which has a certain frosted effect and can play a diffuse reflection role, making the light more soft and not dazzling.
Processing technology
about project1. Screen printing process: processing screen printing patterns.
2. Opening, edging and other technology: the glass can be perforated and trenched, special-shaped step processing, edging cutting, etc., to meet the design needs of different lamps, such as manufacturers can process customized perforated and trenched special-shaped step ultra-white tempered glass edging cutting.
The temperature change and stress formation process of tempered glass during heating and quenching:
Temperature change of tempered glass during heating and quench cooling.
ote: From here it can be understood that once the glass enters the furnace, due to the temperature difference between the inner and outer layers of the glass, the stress of the inner and outer layers of the glass, so the thick glass should be heated slowly and the temperature should be lower, otherwise the glass will break in the furnace due to the temperature difference between the inside and the outside.
Initial heating stage
The glass sheet is heated from room temperature into the tempering furnace, because the glass is a bad conductor of heat, so at this time the inner layer temperature is low, the outer layer temperature is high, the outer layer begins to expand, the inner layer is not expanded, so the expansion of the outer layer is suppressed by the inner layer surface generated temporary compressive stress, the center layer is tensile stress, due to the high compression resistance of the glass, so although the glass sheet is heated rapidly, it is not broken.
Continue heating stage
The glass continues to heat, the temperature difference between the inner and outer layers of the glass decreases, and the inner and outer layers reach the tempering temperature when the equal stress in the glass plate.
Start the quench phase (1.5-2 seconds before the start of blowing)
When the glass sheet enters the wind grid from the tempering furnace, the temperature of the surface layer drops below the central temperature, and the surface begins to shrink, while the central layer does not shrink, so the contraction of the surface layer is inhibited by the central layer, so that the surface layer is subjected to temporary tensile stress, and the central layer forms compressive stress.
Continue quench phase
The inner and outer layers of the glass are further quenched, the surface layer of the glass has hardened (the temperature has fallen below 500 ° C), stops contracting, and the inner layer also begins to cool and shrink, and the hardened surface layer inhibits the contraction of the inner layer, resulting in a compressive stress on the surface layer and a tensile stress on the inner layer.
Continue quenching (within 12 seconds)
The temperature of the inner and outer layers of the glass is further reduced, and the inner layer of glass is reduced to about 500 ° C at this time, and the contraction is accelerated. At this stage, the compressive stress of the outer layer and the tensile stress of the inner layer have basically formed, but the central layer is still relatively soft and has not completely separated from the viscous flow state, so it is not the final stress state.
Tempering completed (within 20 seconds)
At this stage, the inner and outer layers of glass are completely tempered, the temperature difference between the inner and outer layers is reduced, and the final stress of the tempered glass is formed, that is, the outer surface is the compressive stress, and the inner layer is the tensile stress.
Stress distribution of tempered glass:
- Stage A: Start heating
Temperature distribution: outer layer temperature > inner layer temperature (heating is transmitted from the surface to the inside) - Stage B: Even heating (temperature difference elimination)
Temperature distribution: The temperature difference between the inner and outer layers is reduced to within 10℃ (close to the softening point of the glass)
Process significance: Ensure the glass is in a plastic state and prepare for rapid cooling - Stage C: Start quenching (0-2 seconds, surface curing rapidly)
Cooling method: high-pressure air quenching (surface cooling rate > 100℃/s) - Stage D: Deep chilling (2-5 seconds, critical period of stress reversal)
Temperature gradient: The temperature of the outer layer drops below 300℃, and the inner layer remains >500℃ - Stage E: Continuous cooling (5-12 seconds, stress field setting)
Temperature distribution: The inner layer temperature drops to close to the outer layer (temperature difference <50℃) - Stage F: Cooling is completed (12-20 seconds, residual stress is stable)
Performance impact:
Compressed stress layer resists surface crack propagation → 4-5 times increase in bending strength
Tensile stress layer absorbs fracture energy → particles with obtuse angle after fragmentation
The difference between tempered glass and ordinary glass
Features |
Ordinary glass |
lighting tempered glass |
Material |
Usually plain glass or frosted glass |
Tempered glass |
Intensity |
Low, easy to break |
High, strong impact resistance |
Security |
Sharp fragments are formed after breakage, which poses a security risk |
After breaking, small pieces without acute angles are formed to reduce damage |
Heat resistance |
Generally, the temperature difference is small |
Good heat resistance, can withstand large temperature difference |
Surface treatment |
It can be frosted, painted and other processing |
Smooth surface |
Applications |
It is suitable for occasions with low requirements for strength and safety, such as indoor decorative lights, desk lamps, etc. |
Suitable for high strength and safety requirements, such as chandeliers, floor lamps, outdoor lamps and so on. |
