Ballscrew Doctor
Failure mode:Flaking
Flaking is a typical fatigue failure. Shear stress causes initial crack under the surface of thread,and alrernative contact stress extending cracks to the surface. Material flaking creates holes on the thread surface.
Root cause:
Over loading reaches the fatigue life of material.
Failure mode:Rust and corrosion
Water base liquid, high humidity or high temperature difference environment would cause the material surface get rust, and rust will increase through time.
Root cause:
high humidity environment, water base liquid mixture, anti-rust protection fail.
Failure mode:Overheat and burn marks
Overloading or poor lubrication condition generate abnormal frictional heat, causeing overheat and burn marks on the thread surface.
Root cause:
Lubricant fail, overloading
Failure mode:Cracks
Overloading condition leads to poor circulation of rolling element.The excessive or concentrated load and stress causes wear and cracks on the surface.
Root cause:
excessive impact force, poor circulation
Failure mode:Shaft end fracture
Shaft end bears repeated bending stress during rotating casuing the intial crack start from A→B→C.
Root cause:
Misalignment or insufficient shaft end rigidity
Failure mode:Dust intrusion
Dust particle get into ballscrew causing poor circulation.
Root cause:
Particle size is smaller than dust proof protection.
Failure mode:Water or coolant intrusion
Cutting fliud, or coolant fluid is not compatible with lubricant, causeing deterioration of the lubricant.
Root cause:
lubricant deterioration, protection fail, pipe leaking