Edge finishing is a critical but often underestimated step in the manufacturing and installation of sight glass. When edge treatment such as chamfering or polishing is poorly executed or skipped entirely, serious safety and performance risks can arise, even if the glass material and thickness are correctly selected.

One of the primary risks is stress concentration at sharp edges. Untreated or poorly finished edges act as natural stress risers. Under pressure, thermal cycling, or mechanical load, these areas become the starting point for cracks. In pressurized systems, a small edge defect can quickly propagate into full glass failure.

Reduced impact resistance is another major concern. Sight glass may experience accidental contact during installation or maintenance. Sharp, unpolished edges are far more susceptible to chipping, and even minor edge damage can significantly weaken the entire glass panel, lowering its pressure-bearing capacity.

Inadequate edge finishing also affects sealing performance. Rough or uneven edges can prevent proper gasket contact, leading to uneven compression. This increases the risk of leakage, especially in systems handling hazardous or high-temperature media. Over-tightening bolts to compensate for poor sealing often worsens the problem by introducing additional stress.

From a thermal perspective, poorly finished edges increase the risk of thermal shock failure. Temperature gradients tend to concentrate at edges, and micro-cracks formed during cutting or grinding can rapidly expand when exposed to sudden heating or cooling.

There are also long-term reliability issues. Micro-defects at the edges may not cause immediate failure but can grow over time due to vibration, pressure fluctuations, or chemical corrosion. This shortens service life and increases maintenance frequency.

Proper edge treatment—such as chamfering to remove sharp corners and polishing to eliminate micro-cracks—greatly improves safety and durability. In high-risk applications, enhanced edge finishing is often required by industry standards.

In summary, inadequate edge finishing of sight glass can lead to stress concentration, reduced strength, sealing failures, thermal shock sensitivity, and premature failure. Attention to edge quality is essential for ensuring safe, reliable, and long-lasting operation.