A single drop of argon leaked in, rendering "&"the entire furnace unusable.

At the end of the year before last, a customer called, saying that a furnace of high-purity graphite material had completely oxidized and turned white, rendering the entire furnace unusable. The problem ultimately ste"&"mmed from an inconspicuous O-ring; the customer hadn't performed a crucial leak check before starting the furnace. —An aged and deformed fluororubber ring on the flange sealing surface allowed a small amount of air to leak into the furnace.

Core Sealing Design

Water-Cooled Flange

On all major sealing surfaces—furnace door, electrode leads, and pipe interfaces—a metal flange with a built-in water-cooling channel is designed. "&"Cooling water flows continuously, strictly controlling the flange temperature below 60℃.

Fluororubber O-rings

Made of high-quality fluororubber material, with a long-term operating temperature range of -20℃ to +200"&"℃. Under water-cooling protection, the actual operating temperature is far below the upper limit of the temperature resistance, almost eliminating thermal aging and maintaining consistent elasticity and sealing performance for decades.

Sealing Performance Quantification Standards

• Micro Positive Pressure Furnace: After closing all valves, the pressure rise rate is ≤100Pa/h
• Vacuum Furnace: After turning off th"&"e vacuum pump, the pressure rise rate is ≤0.67Pa/min (approximately 40Pa/h)

Each piece of equipment undergoes rigorous pressure rise rate testing before leaving the factory and during on-site acceptance, and the data is recorded in the acc"&"eptance report.

Long-term Sealing Guarantee

Maintenance Recommendations: All O-rings are installed in easily re"&"movable water-cooled flange grooves. During annual maintenance, check the condition of the O-rings—for signs of aging, hardening, cracking, deformation, or chemical corrosion. Replace them promptly if problems are found; don't wait until a leak occurs. A "&"set of O-rings doesn't cost much, but the loss from scrapping an entire batch of products can be substantial.