ABB's new motor for the process industries features improved cooling to
double the operational life of bearings and windings, thus addressing the
causes of 90% of motor failures
Qualifying for the highest European efficiency class, eff1, and rated
from 4-710kW, ABB's new M3000 'Motor for Process Industries' is intended
for applications involving high costs for unplanned stoppages, such as
pulp & paper, metals, building materials, chemical, water and cement
industries.
This is a motor designed specifically for applications with long
continuous running hours, high energy costs and even higher downtime
costs, says Steve Ruddell, general manager, electrical machines, for ABB
in the UK. In recent years, motor manufacturers have tended to economise
on materials to save costs. This motor bucks that trend and is aimed at
discerning users who have realised that better quality motors demand a
higher purchase price but cost significantly less in the long run.
The M3000, with its new bearing end-shield and housing, features 20-30%
greater cooling surface than the previous motor generation, reducing the
internal temperature significantly. This gives longer component life and
protects the motor from overheating, even when covered with dust.
Particular attention has been paid to the design of the bearing housing,
as some 70% of motor failures in industry are due to bearing failure.
With improved cooling, lubrication intervals are 50% longer because the
lower temperature increases the life of the bearing grease. The motors
are fitted with SPM nipples for bearing monitoring as standard, and have
dedicated sites for vibration monitoring. ABB has also re-introduced the
valve disc to the range. This extracts excess grease from the bearing,
protecting against over-greasing (which can cause bearing failure) by
pushing out expended and/or excess grease. The high efficiency of the
motor, moreover, means lower heat losses, resulting in lower winding
temperature and a reduction in the incidence of winding failure - the
cause of 20% of motor failures.
The motor housing has been generally strengthened. For example, a new
foundry method has been developed following analysis of the resonance
frequencies of the casing, minimising vibrations. The larger terminal box
enables easy servicing. Using a cable flange, the terminal box features a
large recess where the cable is placed, rather than the standard
arrangement with insertion through a drilled hole in the side. A spacious
interior accommodates the bends of heavy gauge cables. A new terminal
board also makes the connection easier and faster.
The M3000 is available in IEC frame sizes 112-400, 4-710kW. Cast iron
enclosure is standard from frame size 160 and above, while aluminium is
used in frame sizes 112-132. All ABB motors are suitable for use with a
variable speed drive as standard. Special attention has been paid to ease
of installation for encoders and forced ventilation, and numerous factory
supported design modifications are available.
Five minutes of downtime costs as much as a new motor. Our target is no
unplanned downtime, says Ulf Ringström, responsible for preventative
maintenance at paper mill SCA Ortviken in Sundsvall, northern Sweden, and
part of an industry reference group during development of the new motor.
This is a motor that can handle the tough environment in a process
plant, Ringström says. It is solidly built and easy to service. Its
high efficiency reduces energy consumption, which saves money and reduces
the environmental impact, helping us reach our ISO14001 targets. We have
about 3,500 motors, some of them in operation for decades. When these are
replaced, we need a motor that is built to last.