Real-time monitoring for Ebara vacuum pumps

Mechanical / Rotor Causes

• Rotor clash - The rotors spin with very tight clearnances and no lubricating film between them. Foreign particles, thermal expansion, or bearing wear can cause the rotors to contact each other, leading to seizure or violent destruction.
• Bearing failure - bearings are the main wear item; if they fail, rotors lose their precise positioning and clash.
• Shaft seal failure - can allow process gas or cooling water into the pump body, causing corrosion or sudden rotor clash.

Thermal Causes

• Overheating - dry pumps rely on cooling (water or air). Loss of coolant flow causes thermal expansion of rotors, closing clearances until they clash.
• Pumping condesables - if solvents or water vapor condense inside the pump, liquid slugging can hydraulically shock the rotors

Process / Chemical Causes

• Particle ingestion - solid particles (powder, flakes, deposits) from the process get into the pump and jam or score rotors
• Polymerization - reactive process gases (silane, TEOS, etc.) can deposit solids inside the pump body, gradually building up until the rotor seizes
• Corrosion - aggressive gases (halogens, acids) attack internal surfaces over time, eventually causing structural failure or particle generation

Electrical / Control Causes

• Running against a closed valve - pumping into a blocked outlet builds extreme pressure and heat rapidly
• Sudden venting - rapidly venting atmosphere into a pump at high speed can cause reverse rotation or rotor clash
• Power interruption at high pressure - the pump decelerates unevenly, sometimes causing backflow-driven reverse spin