The glass industry has strict standards for the use of compressed air, mainly covering pressure, flow, quality (cleanliness, dryness, oil content) and stability, etc. The specific standard requirements are as follows:
pressure and flow
- pressure: The pressure requirements of compressed air in the glass industry vary depending on the specific application scenario. For example, there are certain requirements on the pressure of compressed air in scenarios such as combustion-supporting during the combustion of molten glass in the production line, purging of residual materials in the cavity of idle oil (powder and natural gas) and cooling and cooling protection of the cavity during the fire exchange process. Generally speaking, the gas pressure at each gas point in the flat glass factory does not exceed 5-7kgf/cm² gauge pressure (about 0.5-0.7MPa), but some special scenarios may require higher or lower pressures. For glass plants that use natural gas as fuel, the pressure requirement of compressed air for furnace fuel injection is relatively low, and 2kgf/cm² gauge pressure (about 0.2MPa) is sufficient when reaching the user. Therefore, an air compressor unit with a gas supply pressure of 3-3.5kgf/cm² gauge pressure (about 0.3-0.35MPa) can be configured.
- Flow: Traffic requirements also vary by application scenario. For example, in scenarios such as coke powder pipeline transportation and blowing, compressed air is required to provide reliable transportation speeds to reduce production and transportation costs and avoid the impact of ultrafine dust diffusion on the surrounding environment during transportation. Therefore, when selecting an air compressor, it is necessary to select the type according to the actual flow demand.
Quality Requirements
- cleanliness the glass industry requires high cleanliness of compressed air. The dust particle diameter and dust content in the compressed air need to be controlled at a very low level to avoid the impact on product quality and production environment. For example, in a TFT-LCD glass substrate production line, compressed air is required to have a dust particle diameter of ≤ 0.3 μm and a dust content of ≤ 1000 particles/m & sup3;.
- dryness: The dryness of compressed air is also one of the key indicators. Excessive humidity may cause problems such as product moisture and equipment corrosion. Therefore, the glass industry usually requires a low pressure dew point temperature of compressed air to ensure its dryness. For example, in a TFT-LCD glass substrate production line, the pressure dew point temperature of compressed air is required to be − 33 ° C. or lower.
- Oil content: Oil in compressed air may pollute product quality and production environment. As a result, the glass industry typically requires very low or zero oil content in compressed air. This is usually achieved by using an oil-free compressor or equipped with an efficient oil separator.
Stability requirements
- the glass industry requires high stability of compressed air. Gas supply interruption or pressure fluctuation may lead to production line downtime, product quality degradation and other serious consequences. Therefore, when choosing an air compressor and designing an air supply system, it is necessary to fully consider its stability and reliability. For example, multiple air compressors can be operated in parallel to improve the stability and reliability of gas supply; at the same time, auxiliary equipment such as gas storage tanks need to be equipped to cope with gas demand in emergencies.
