Question:What protective gases are supported? Can the gas inlet/outlet be precisely controlled using mass flow controllers? What is the pressure control range?

Detailed Answer:
Atmosphere control is the soul of the graphitization process. Different gas types and pressure environments directly determine the final performance and purity of the products. Our equipment provides refined control solutions for this purpose.

I. Gas Selection: Temperature is the Dividing Line

• Operating Conditions Below 2200°C:In this temperature range,high-purity nitrogen (N?)serves as a highly cost-effective protective gas. It effectively isolates oxygen, and its cost is significantly lower than that of argon.

• High-Temperature Operating Conditions (2200°C to 3200°C):When the temperature exceeds 2200°C, nitrogen reacts with graphite to form cyanides. This not only contaminates the products but also severely corrodes the graphite components inside the furnace. Therefore, the use of chemically inerthigh-purity argon (Ar)is mandatory. We strongly recommend an argon purity of no less than99.999%.

II. Control Precision: From "Approximate" to "Precise"

We have moved beyond simple on/off valve control and now standardly employMass Flow Controllers (MFCs)to manage gas inlet. An MFC functions like a precise faucet, allowing for accurate setting and maintenance of a constant gas flow rate (unit: liters per minute) into the furnace. The flow control accuracy can reach±1.5%, ensuring high process repeatability.
On the exhaust side, an automatic regulating valve is typically installed, working in conjunction with a furnace pressure sensor.

III. Pressure Range: The "Safety Zone" of Slight Positive Pressure

The pressure inside the furnace is generally maintained in aslight positive pressurestate, meaning slightly higher than the external atmospheric pressure. This creates a "gas curtain" that prevents air from infiltrating. The typical pressure control range for our equipment is between500 Pa and 1500 Pa (gauge pressure).
By setting a target pressure value, the system automatically adjusts the flow rate of the inlet MFC and the opening of the exhaust valve to stabilize the furnace pressure at the set point, creating a dynamically balanced, pure environment.

Core Value:This precise atmosphere control system ensures that every batch of products is processed under an identical protective environment. It is a key technological component for guaranteeing stable performance consistency across different production batches.

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