Davis Tube Tester

Davis tube is a laboratory instrument used for separating small samples of strongly magnetic ores into magnetic and non-magnetic fractions.
Widely used for evaluating the separability of magnetic ores.

Operation

• Feed sample into inclined tube
• Apply magnetic field
• Introduce water flow and agitation
• Magnetic particles remain in tube
• Non-magnetic particles are washed out
• Collect, dry, and analyze separated fractions

Working Principle

• The sample is passed through an inclined tube placed between electromagnet poles.
• Strongly magnetic particles are held in the magnetic field, while weakly magnetic and non-magnetic particles are washed away by water.
• Agitation and water flow assist in separating particles based on magnetic susceptibility.

Additional Information

• Developed in 1921 and design remains largely unchanged
• Used to determine magnetic separation characteristics (MSC)
• Results depend on field strength and operating conditions
• Effective mainly for magnetite and similar magnetic minerals

• Magnetic ore testing
• Evaluation of magnetic separation efficiency
• Mineral processing research
• Iron ore analysis (magnetite, taconite, roasted ores)

Tube diameter :

• 25 mm

Tube inclination :

• Approximately 45° (adjustable)

Magnetic field strength :

• Adjustable up to 3500 Gauss
• Higher models available up to 4500 Gauss

Recommended magnetic induction :

• ~0.1 Tesla (standard drum comparison)
• ~0.3 Tesla (for rare-earth systems)

Sample size :

• ~10 g

Agitation :

• 60 to 150 cycles per minute

Water flow rate :

• 50 to 500 cc per minute

Test duration :

• 3 to 20 minutes

• Laboratory-scale magnetic separation
• Adjustable magnetic field strength
• Motorized agitation system
• Accurate separation of magnetic and non-magnetic fractions
• Standard equipment for mineral testing
• Suitable for fine pulverized samples