Industrial carbon brush
Industrial carbon brush is one of most important products of BOYO CARBON. The field of industrial brushes covers a wide range of materials and applications. Such as: DC Motors and Generators, turbo-generator ring, Ac Motor rings, low voltage Generators, Plating Generators, Regulating and control Devices, Torpedo motors , etc.
The function of carbon brush is as fixed parts and revolving parts of electric motors and conduct current between commutators or slip rings. The current direction will be altered 180o when the coil short by carbon brush in the Dc motors or Ac commutator motors.
How to manufacture the carbon brush? The following is our production flow diagram:
purchase the needed material, such as: carbon black, carbon powder, asphalt, resin, electrolytic tough pitch copper powder, olefin, lubricating grease and other metal powder,etc.
prepare the primal carbon block (mixing the carbon powder and asphalt bond and other material then to press to block shape or rod shape. And then baking in the 850 ¡æ to get rid of the volatile of asphalt.)
break up the primal carbon block: we need to use the advanced crusher which had perfect rotate speed, charge, amount of winding of air compartmentation device,etc.
mix the many kinds of material to a carbon grade. We use the kneading machine to mix those materials. And general speaking, 150 ¡æ will be good to knead.
Pressing to the needed shape such as block or rod, etc. All the shape will be according to the special mould. General speaking, the mould size should be: the thickness:30 -100mm , the width:100 -150mm ,the length:200 -250mm . or the length and width:150 -300mm , the thickness:30 -100mm . The equipment is 50tons -1500tons press machine.
Backing the block in the tunnel furnace with around 1000 ¡æ . General speaking the baking period is about 30days to 60days.
Impregnate the semi-manufactured goods with resin or asphalt in the pressure vessel, and then after second baking to make the resin or asphalt carbonize.
Graphitization is most important for the carbon blocks. After the graphitization the carbon brush will be called electro-graphite carbon brush. Graphitization is through high temperature furnace which should be reached to 2500 -3000 ¡æ . After graphitization the rough carbon block will be has more lower resistance and more lower friction rate. And lubricate capability will be more better than before.
The second impregnate the rough carbon block. With resin, asphalt, lubricant, and olefin according to special applications. After the impregnation the carbon brush will increase the touch resistance and deduct the abrasion with the slip rings or commutators.
Strict Inspection to upper every process, such as granularity inspection, carbon block density inspection, carbon block mechanism intensity inspection, carbon brush resistance, carbon brush modulus of elasticity inspection, ash content,etc.