In process industries such as chemical, pharmaceutical, food, and energy production sites, a large amount of material reactions, mixing, and transportation are completed inside sealed tanks and pressure vessels. Without direct observation of internal working conditions, it is difficult to control the production status. The flange sight glass is an industrial observation window installed on pressure vessels, reaction vessels, and storage tanks, and is vividly referred to as the "industrial eye" of equipment.
The circular flange mirror in this picture consists of two metal flanges, multiple sets of fastening bolts, sealing gaskets, and a tempered borosilicate mirror glass in the middle. By relying on bolts to evenly compress the two flanges and squeeze the middle seal, sealing under high pressure conditions is achieved. Through high-strength transparent glass, operators can intuitively view the material level, flow status, reaction color, and sedimentation inside the container without stopping the machine or opening the lid, monitor production in real time, and avoid equipment abnormal risks
Core Structure and Materials
Flange body: 304 and 316L stainless steel are commonly used, but carbon steel WCB can also be selected. Stainless steel material is corrosion-resistant and suitable for food, medicine, and highly corrosive chemical media; Carbon steel has a lower cost and is commonly used in ordinary water and oil conditions. Flange forging processing, high flatness, ensuring sealing performance.
Mirror glass: The mainstream is tempered borosilicate glass, which is temperature resistant, pressure resistant, and resistant to cold and hot impacts; Quartz glass can be selected for high temperature scenarios to meet the needs of higher temperature environments. Glass undergoes strict pressure testing to ensure the safety of high-pressure vessel use.
Sealing gasket: PTFE, silicone, and rubber gaskets are optional, selected according to the acidity, alkalinity, and temperature of the medium to prevent medium leakage.
Fasteners: Stainless steel bolts and nuts, evenly locking the flange to ensure even stress on the sealing surface and avoid glass damage caused by local stress.
Application Scenarios：
The flange sight glass is manufactured according to the NB/T47017 pressure vessel standard and is widely assembled on reaction vessels, storage tanks, filters, fermentation tanks, evaporators, and pipeline pressure vessels.
Food and beverage industry: observe the fermentation status and material mixing inside the fermentation tank;
Pharmaceutical industry: Visual monitoring of reaction kettle liquid reaction and crystallization processes;
Petrochemical industry: monitoring medium flow, presence of bubbles, precipitation, and determining reaction progress;
Environmental water treatment and new energy: observation of liquid level and material status inside the tank.
Product Advantages：
Visual monitoring: without opening or stopping the tank, visually view internal working conditions, and improve production efficiency;
Pressure and temperature resistance: Standardized design, adaptable to pressure ranges of 0.6~2.5MPa, meeting most pressure vessel operating conditions;
Flexible material: Multiple combinations of flanges, glass, and seals, suitable for different working conditions such as corrosion, high temperature, and hygiene level;
Easy disassembly and maintenance: The bolt flange structure can be quickly disassembled in the later stage, and the glass and sealing gasket can be replaced, making maintenance convenient.
Precautions for use:
The flange sight glass is a pressure bearing safety component, and the selection needs to match the pressure, temperature, and medium corrosion level of the equipment. During installation,
bolts should be evenly tightened diagonally to prevent uneven stress on the glass from causing it to explode; Avoid hard objects hitting the glass during operation; Regularly check for gasket
aging and glass cracks. If any damage occurs, immediately shut down for replacement to ensure safe production.
The small circular window may seem simple, but it is an essential safety accessory for sealed chemical equipment. It transforms the invisible internal production status into visualization, laying a
solid quality and safety defense line for continuous industrial production.
