Archives for April 2020

Do you know the primary functions of lubrication?

1. Friction Control -to lubricate all true rolling contacts, balls or rollers by hydro dynamically separating moving surfaces simply put “Separating Components By Hydraulic Film”
2. Lubricate Non-Rolling, that part of the contact between the raceways and all rolling elements that are not rolling
3. Lubricate Sliding, that contact which exists between the retainer and other parts of the bearing
4. Corrosion Control, to protect the highly finished surfaces of the roller elements and rings from corrosion. Including the bearing housing(s
5. Temperature Control, provide a heat transfer medium (cooling).
6. Block Contamination, grease acts as a seal to prevent entry of contaminants

We are always looking at ways to provide our customers the reliability tools necessary to keep their plants up and running strong.  Over the next several weeks we will be hosting webinars focused on just that – reliability.

Go to meeting invite with link will be sent after registering via email

Upcoming:

Electric Motor Greasing:

Part 1 and 2: 4/29 /20 and 5/6/20 from 1 PM to 1:30 PM

Part 1: Traditional Greasing Program on 4/29

• Proper type of grease
• Mixing of grease
• New energy efficient greases
• Ball vs Roller bearing lubrication requirements
• NEMA vs IEC Motor lubrication
• Initial Commissioning alignment and proper greasing
• Purge Plug
• Automatic greasers -vs- hand greasers
• Grease zerks outside the motor frame for accessibility
• Storage or end of season Greasing
• Hourly scheduling for greasing
• Repair and actual failure observations

Part 2: Proactive Greasing Program on 5/6

• UE style greasing with grease buddy system.
• Route based by DB level greasing
• Use as greasing tool.
• Still limit the amount of grease, if DB does not change.
• Opening purge plug still necessary with this system?
• How do I know, when I have a bad bearing?

(Scroll to bottom for pictures.)

There is a saying that we are all familiar with “make the best out of a bad situation”– something our country knows all too well right now. This customer had a bad situation but with Root Cause Failure Analysis (RCFA) performed by our technicians, we were able to find a long-term solution to mitigate and protect against future operator induced failures.

This D.I.E customer had been suffering multiple failures of their 250 HP motors. During the RCFA, we noted the shafts would not rotate. Upon disassembly we noted a potential lubrication issue as grease had been sprayed over the stator windings typically a potential sign of excessive lubrication. We discovered the rotor bars were melted at the center of the rotor core usually caused by stalling or excessive load in conditions where the rotor cannot accelerate to full speed. The resulting excessive rotor slip, and lack of acceleration, lead to high frequency and current at the rotor surface.

As a valued reliability partner we provided support during the consideration of methods to mitigate future failures from suspected thermal overload due to stalling or repetitive starting issues.  We presented our findings to the customer.  They have proposed the installation of Reduced-Voltage-Soft -Starters (RVSS) to their management as a best practice solution to prevent future losses on these applications. To install RVSS starters on three pieces of equipment would require a roughly $70,000 investment.  The customer has has found that more than $70,000 annually  was invested  in motor replacements for these applications. This does not include the removal, installation, or for the production losses incurred.  

Click on photos to enlarge.