Technologies in Manufacturing Maximizing machinery health with - PowerPoint PPT Presentation

Predictive Monitoring Technologies in Manufacturing Maximizing machinery health with condition based monitoring

CBM Goals ZERO unplanned downtime  – Maximize Equipment Availability & Reliability • Plan ALL Maintenance - HOW? Be competitive today with a plant that is typically more than 40 years old  – Extend Machinery Life & Rebuilds Running equipment beyond its design capacity Increased throughput without RISK of machine failure ?

Reliability Strategy:  What maintenance does the machine need during the next planned shutdown? – Are the spare parts in my inventory?  Can the equipment run beyond the next scheduled outage?  Are the machines running without excess vibration? – Are alignment and balancing work orders needed – Is lubrication proper and adequate – Thermography needed?

What is Vibration?  Vibration is the motion of a body about a reference point caused by an undesirable mechanical force.

ISO 10816-3 inch/s RMS mm/s RMS VERY BAD VELOCITY 2-1000hz >120rpm VELOCITY 10-1000hz >600rpm ↖ 1 ↖ 25.4 ALARM D ↖ 0.433 ↖ 11 WARNING C ↖ 0.279 ↖ 7.1 ↖ 0.177 ↖ 4.5 GOOD B ↖ 0.137 ↖ 3.5 ↖ 0.11 ↖ 2.8 ↖ 0.09 ↖ 2.3 VERY GOOD A ↖ 0.055 ↖ 1.4 rigid flexible rigid flexible foundation type 160mm < H < 315 H > 315 motor center hight group 2 15kw <300kw group 1 300kw <50 mw group / class medium sized machines large sized machines machine type A New Machine Condition C Unsatisfactory B Normal Operation D Damage Occuring Notes: 1 - The shaft hight, H of a machine is the distance between the centerline of the shaft and the baseplate of the machine 2 - The shaft hight of a machine with raised feet, or any vertical machine , is to be taken as the shaft height of a machine in the same basic frame, but the horizontal shaft foot-mounting type. When frame is unknown, half the machine diameter should be used.

Rules of Vibration Analysis  Each machine fault generates a specific vibration pattern  The frequency is determined by machine speed and design  The “FFT” process is used to separate a vibration signal into information about individual faults

FFT Spectrum Analysis FFT Spectrum shows component vibration signals at their respective frequencies amplitude Frequency

Spectrum Analysis Techniques Collect Useful  Information Analyze 

Spectrum Analysis Techniques Collect Useful Information  Analyze  1800 RPM 2400 RPM 5 blade fan motor gearbox gearmesh frequencies

A Typical FFT Spectrum Specific peaks typically correlate to Specific machine faults Related to machine speed

Measurement Point Locations MOH MIH PIH POH MOV MIV PIV POV POA MOA 2 per bearing + 1 axial measurement per shaft

Three Rules of Diagnosis  Each machine fault generates a specific vibration pattern.  The frequency of the vibration is determined by the machine geometry and operating speed.  A single vibration measurement provides information about multiple components

Diagnosing Machine Faults  Imbalance  Misalignment  General looseness or wear  Bearing defects  Gear defects  and many more...

What is a Vibration Program?  Expertise, Technology, and Work Processes that – Prevent Unexpected Downtime • By assuring machines do not fail catastrophically – Extend Machine Life and Optimize Performance • By detecting & correcting root cause conditions that cause excessive wear Do the right work… – Allow You To Work Efficiently At the right time… With the right methods… • By trending progressing faults and… • Coordinating repairs to occur at planned outages

So what can Vibration Analysis detect?  Track progressing stages of Bearing Failure  Identify/correct Imbalance and Misalignment  Identify/correct Resonance  Identify Mechanical Wear in couplings, bearings, support structures, etc.  Detect other defects such as: – Lube failure / soft foot / broken rotor bars – Pump cavitation, and many more…

Case Histories-continuous monitoring Cement Mill:  – On-line vibration monitoring detect resonant condition – Air handler with intermittent high vibration • Resonance occurs when baffle open at ~61%.  Power Plant: – On-line vibration extends maintenance intervals • Preventive turbine maintenance every 5 years – Unnecessary maintenance can induce faults! • Extend from 6 – 10 years with on-line monitoring – Average repair cost around $1 million

Case Histories-continuous monitoring Automotive Plant:  – On-line vibration monitoring ensures quality • Continuous display of machine tool condition – Monitoring tool tip – Plan change-outs during shift changes. – Confirm quality of rebuilds Waste Water Facility:  – On-line vibration helps with compliance • Spill risk is minimized • Operators are notified immediately of upset • Mandatory condition assessments of all equipment

Case Histories-monitoring peak and phase Decanter Plant Centrifuge:  – One times turning speed • Phase is same • Peak amplitude changes • Diagnosis? Balancing Stand:  – Peak vibration is same – Phase changes – Diagnosis?

Case Histories-Inspection with Strobe Light Textile Plant: High 1x vibration on  Pulley assembly. Strobe inspection  Showed damaged pulley on motor  Polyester Plant: Plant balanced fan twice to eliminate high 1x vib Strobe inspection showed cracked Fan fin inside motor fan guard

Case Histories- Coherence Nonwoven Plant:  High floor vibration at 565 RPM  What is cause  Strobed the equipment room  Air handler fan stopped  Belt dressing on top of pully cage  Coherence test showed .95  Correlation  Fan inspection showed damaged  Blade  Plant had moved equipment from  area 

Case Histories-Cracked end ring on motor Automotive Plant:  400 Ton Refrigeration unit  1x peak was growing with temp  Amp draw guage flickering back  And forth 

Where should predictive maintenance be used? Plant Equipment 0% Predictive 20%  Predictive Critical – Critical to production & Essential 40% Preventive 60%  Preventive – Support equipment Essential 80% Reactive Reactive Non-  essential – Easy/Inexpensive to replace 100%

Elements of a Condition monitoring Program Training Diagnostic and corrective tools Services

7) Document Business & Maintenance Implications  Document: – Diagnoses – Recommendations – Accuracy – Reoccurring faults – Mean time between service – Production gains – Cost savings – Financial impact

Summary: Key Points in a CBM Program  Expertise, Technology, and Work Processes that – Prevent Unexpected Downtime • By assuring machines do not fail catastrophically – Extend Machine Life and Optimize Performance • By detecting & correcting root cause conditions that cause excessive wear – Allow You To Work Efficiently • By trending progressing faults and… • Coordinating repairs to occur at planned outages