How to Produce 80 Mesh Graphite Powder for Refractory Applications

80 mesh graphite powder is the most widely used specification for refractory materials. Its sieve aperture is about 0.18 mm, featuring moderate particle size, good thermal conductivity, anti-oxidation and high temperature resistance. It is mainly used for refractory bricks, furnace castables, steel ladle linings and high-temperature kiln refractory layers. This production process focuses on stable particle size, low impurity and high fixed carbon content, no need for ultra-fine grinding.

1. Raw Material Selection Standard

• Preferred material: Natural flake graphite raw ore
• Fixed carbon of raw material: ≥85%
• Strictly control impurities: low silicon, low aluminum, low sulfur and low iron
• Remove large gangue, soil and hard rock in advance
• Raw material moisture: controlled below 5% before processing

2. Complete Production Process Flow

Step 1 Manual sorting & primary impurity removal

Pick out large non-graphite stones and sundries to reduce wear of crushing equipment.

Step 2 Coarse crushing

Use jaw crusher to crush bulk graphite ore into 10–25 mm small particles, uniform feeding for next process.

Step 3 Low-temperature drying

Dry raw materials in rotary dryer at 60–90 °C, final moisture ≤0.8%, prevent adhesion and sieve blocking.

Step 4 Medium crushing (core process)

Adopt hammer mill or impact mill for medium grinding, adjust rotating speed to avoid over-grinding into fine powder.

This step controls most materials within 80 mesh range.

Step 5 Accurate sieving classification

Equip linear vibrating screen with 80 mesh standard screen net:

• Qualified powder passing through screen: finished 80 mesh graphite powder
• Oversized coarse particles return to crusher for re-crushingStrictly control oversize rate below 3%.

Step 6 Iron removal purification

Install strong magnetic separator to remove iron impurities generated during crushing, improve refractory high-temperature stability.

Step 7 Material homogenization mixing

Mix qualified graphite powder evenly to ensure consistent carbon content and particle size of each batch.

Step 8 Dust collection & finished packaging

Use pulse dust collector to recover fine powder, then pack into ton bag or woven bag for storage and delivery.

3. Matching Production Equipment List

1. Jaw crusher
2. Rotary drying machine
3. Hammer crusher / impact crusher
4. Linear vibrating screen (80 mesh)
5. Magnetic iron remover
6. Pulse dust collector
7. Mixing blender

4. Key Production Control Points

1. Do not use ultra-fine grinding mill, to avoid producing too much fine powder lower refractory bulk density.
2. Control crusher running speed moderately, slow speed is better for stable 80 mesh particle size.
3. Keep screening equipment clean regularly to prevent mesh hole blockage.
4. Strictly control drying temperature, high temperature will reduce graphite fixed carbon activity.
5. Keep workshop dry, avoid finished powder absorbing moisture and agglomerating.

5. Refractory Grade 80 Mesh Graphite Powder Quality Index

• Fixed carbon: 80%–95% (customizable)
• Ash content: ≤8%
• Volatile matter: ≤2.5%
• Moisture: ≤0.8%
• Passing rate of 80 mesh: ≥95%
• Iron content: ≤0.5%
• Good high temperature anti-oxidation performance

6. Common Production Problems & Solutions

1. Too many fine powders

Reason: Too high grinding speed

• Solution: Reduce host speed, increase screen feeding volume
• High moisture finished powder

Reason: Insufficient drying

• Solution: Extend drying time or raise drying temperature properly
• Unstable carbon content

Reason: Uneven raw material mixing

• Solution: Strengthen raw material pre-blending
• Screen blocking

Reason: Raw material with soil and high moisture

1. Solution: Strengthen pre-washing and drying process

7. Application Advantage

80 mesh graphite powder can effectively improve thermal shock resistance, thermal conductivity and wear resistance of refractory products, reduce sintering shrinkage, and extend service life of high-temperature refractory linings.