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Worm gear and worm gear mechanisms are commonly used to transmit motion and power between two staggered shafts. The worm gear and worm gear are equivalent to gears and racks in their middle plane, and the worm gear is similar in shape to a screw. The gear reduction ratio of the worm gear is generally 20:1, sometimes even up to 300:1 or greater.

Worm gears are commonly made of cast tin bronze and aluminum iron bronze; Low speed and unimportant transmissions can use cast iron materials.

Cast iron bronze: good friction, good adhesion resistance, expensive price, slightly lower strength.

Cast aluminum iron bronze: slightly inferior in friction reduction and adhesion resistance, but high in strength and affordable.

Cast iron: gray; Ball ink. To undergo aging treatment and prevent deformation.