Condition Based Maintenance – Monitoring Tools

Hi,

I keep getting updates on new products used in the maintenance field through various online subscriptions.

Here is a link that shows the us of Ultrasound devices in the condition based maintenance strategy. I am not trying to sell the product, but am just trying to propagate the techniques involved. Please connect to the link given below and learn more.

http://www.uesystems.com/new/applications/

KayCee

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Look, Listen and Feel – in Condition Based Maintenance

Hi all,

With due respect to all the gadget geeks and proponents of high-tech equipment to carry out condition based maintenance; the age-old classic forms of observations as indicated below are still valid in the field of condition based maintenance; probably as the first information report function.

Look ………. Listen ………. Feel!

The basics of good maintenance start from the careful, systematic, periodic inspection of equipment and system elements – the first step. Recording of observations is the second step. Analysis of the observations by a maintenance team leader would be the third step.

Essential Safety Precautions for the Look / Listen / Feel Work

Wear all essential personal protection equipment prescribed for each installation. Examples – for high noise areas, ear defenders are a must; eye protection is essential where high dust, fumes, vapours, flying sparks etc conditions exist. Safety shoes are required to be worn in all conditions. Rubber soled shoes with fibre re-inforced toes are to be worn while working on electrical panels and equipment.

Individuals must be deployed for such jobs only after successfully being certified in safety aspects and equipment skills.

Visual inspectionLook

Before starting an equipment or systems: Good maintenance practices exhort users and maintainers to do a full visual inspection of equipment and systems before they are put into use, each time and every time. Such a visual inspection could reveal tell-tale oil or lubricant leaks, discolouration of protective paint due to overheating, corrosion spots, damaged parts, missing elements such as belt / chain guards, dust and debris collection, physical obstruction etc. Clearing all the abnormalities before putting the equipment or systems to use will increase their reliability.

Identifying “Lock Out Tag Out (LOTO)” Conditions: Visual inspection of control (mechanical / electrical) elements will help in identifying the LOTO conditions. In case the equipment is tagged out or locked out; operations are not possible till that condition is cleared by the person who locked it or tagged it.

Running equipment or systems: Periodic visual inspection of equipment or systems while in operation is also essential.

  • This could be done manually by visiting each equipment, looking at the equipment as a whole, checking the relevant critical parameters from their respective meters, checking for abnormal visual vibrations, checking for visible leaks, checking for overheating, checking for spray or flow quality / quantity (example – cooling tower water nozzles),
  • Alternatively, for large installations with high automation and central controls, the visual inspection could be through CCTV cameras, monitoring of parameters through data loggers, online vibration measurement, etc.

ListenListen

This is mostly applicable to equipment with rotating elements (motor driven pumps, fans, compressors etc).

Loose components or sub elements on the equipment may cause audible rattling noise. If left unattended, these could lead to consequential damages.

This technique needs some skill and long involvement of the operator or maintainer with the equipment under his or her charge. The operator / maintainer need to develop a skill on “what to listen to” and on how to identify “wrong noise”. This comes from experience.

On the long run, an operator will be able to make out the change in noise at a motor bearing or a fan air cutting noise due to blade damage. At this point it may be subjective, but a requisition for more precision measurements could be initiated before a major damage occurs.

A long stem screw driver or a simple mechanical stethoscope made out of thin, rigid, long copper tube with a small brass ear cup (a simple washer would do) attached to it could be used as an effective listening aid.

Please be wary that very noisy equipment should not be listened to with unprotected ears and the listening aids mentioned above. Prolonged exposure to loud noise could lead to permanent hearing loss progressively.

FeelFeel

The “Feel” factor is an equally important tool in condition monitoring. One needs to be a bit cautious on this aspect since many of the running equipment could have hot surfaces and may not be directly touchable, without causing harm. On the same lines, there could be system elements that run very cold and touching them with unprotected hands could cause cold burns or skin peeling. The Maintenance managers need to decide on what can be touched to feel.

Safety is very important here since the “Feel” actions are generally done on running equipment. Care should be taken to avoid putting the palm very close to moving parts

The “Feel” gives you some idea on the difference in temperature, non-visual vibration level changes, flow quality (turbulent or otherwise), presence or absence of flow, presence or absence of a liquid in a container or pipe, heaviness or lightness of an item, rigidity or flexibility of an item, speed / velocity changes etc. “Feel” is  through the skin and the palm is the best suited body part for the purpose.

Combination of Look, Listen and Feel

Practised together, the above combination provides a very thorough basic condition monitoring technique. experience on the field and safe working habits bring in a slew of benefits in OEE and reliability.

One thing good about this is that it is a value addition to the service rather than eating into a lean and mean budget allocation.

The observations from the above technique could lead to more precise measurements of temperature gradient using a thermal imaging camera, vibration monitoring using hand-held equipment etc.

Visual Factory

Appropriate signage placed at strategic locations could make the Look, Listen and Feel inspection systematic.

Place pictures of eyes where visual inspection needs to be done. Pictures of ears and palm would indicate the listen and feel activities.

Added to these, station markings arrows could be marked on the ground indicating which positions the operator or maintainer should take and direction to face the equipment to make an observation.

Further arrow markings to indicate the direction to be taken while making observations could be done to optimise effort and time taken for observations.

Tail Piece

Smell The human nose can discriminate difference in smells. For example, the smell of overheated or burning oil in a diesel engine has a very recognizable odour.

Heated or burning electric insulation also has a very distinct odour.

The smell of a burning flourescent lamp choke is very discernible.

Smell of a dead rodent in a ventilation duct can be very disturbing.

So, the nose also can be a very reliable sensory organ in equipment / system condition monitoring.

Comments are solicited on my thoughts expressed in this post.

KayCee

Better Indoor Air Quality through Structured Cleaning

A few tips to cleaning

1. Cleaning Chemicals.     Choose low-emitting maintenance chemicals to reduce VOCs. Volatile organic chemicals, or VOCs, present in some traditional cleaning chemicals can contribute adversely to indoor air quality and lead to Volatile organicity issues. Careful selection of cleaning chemicals can help reduce the risks.
2. Door Mat System.      Place quality walk-off mats at all entrances. The best way to reduce contamination is to stop it before entering the door. When dirt, allergens and the like are successfully trapped in walk-off mats, carpets, textiles and surfaces can stay cleaner.
3. Vacuum Cleaning.      Vacuum carpet regularly. Regular vacuum cleaning perhaps is the most important aspect of a preventative maintenance system; this significantly reduce indoor allergens. In general, weekly cleaning works for most surfaces, while high traffic areas may require more frequent vacuuming.
4. Deep Cleaning.        Deep clean carpet on a regular schedule. Vacuuming removes the bulk of
contaminants, but periodic deep cleaning is also important. One alternative for carpet maintenance, dry polymer cleaning, can also remove up to 99 percent of allergens from the air when used with a quality, properly maintained HVAC system.
5. Other Soft Fabric.    Don’t forget textiles. Carpet, upholstery, fabric panels and window treatments act as filters, collecting airborne contaminants. Make sure to include these materials in any preventative maintenance regimen.
6. Mold.    Safeguard against mold. In addition to being unsightly, mold can negatively impact the health of those exposed. Prevent mold growth, and avoid the problem, by choosing carpet cleaning and maintenance techniques that remove the bulk of moisture used in the process, and ensuring that HVAC systems are in proper working order.

Maintain today, sustain tomorrow. In addition to reducing indoor allergens and contaminants, scheduled maintenance can also prolong the life of carpet, upholstery and other soft materials in your facility. 

Ten Tips to Cut Energy Costs

Recession or in life of plenty, energy produced from hydrocarbons is finite. We need to conserve energy use so that the availability of such resources could be stretched farther.

Renewable and alternative energy sources are still catching up.

There is big question mark on nuclear energy after the latest Japanese disaster.

Even in a comparatively poor country such as India, changing life styles and global warming have added on to the per capita energy consumption.

  • Gone are those days when people used to walk or cycle to work; or mostly use public transportation.
  • Homes without refrigerators are rare.
  • Most urban homes have at least one air conditioner.
  • Two wheelers and televisions are essential commodities these days.
  • We need electrically operated treadmills to exercise, rather than walking for free on the roads or a park.
  • The list will go on……….

It is more difficult to change adapted or adopted individual life styles. Increasing the awareness on the impending energy crisis through events such as “Earth Hour” etc would help individuals in shaping their energy consumption.

When it comes to commercial buildings (offices / factories / hospital complexes / hotels / amusement parks / public utility buildings etc) that account for a large chunk of energy consumption, it is no different except for some parameters. Here are some tips to save energy and with that the operations cost.

  • 1 Reduce Site External Illumination. Keeping in mind the safety and security needs, reduce the non essential lighting.
  • 2 Revamp Your Facility Operations. The measures would include:
  • Scheduling equipment off time when not needed
  • Periodic calibration and resetting of all automatic controls
  • Adding features to existing controls to improve system efficiency
  • Repair insulation, seals, dampers and valves on equipment or systems to reduce or eliminate energy wastage
  • 3 Make Energy conservation a community initiative. When you get the top management, occupants / users, security personnel, maintenance groups, IT teams involved in the initiative, the results are better.
  • 4 Turn off vending machine lights. Per machine save may be minimal, but the total long term benefits are large.
  • 5 Encourage use of stairs where possible. Keep it as a challenge, that people will take up. Highlight the benefits to individual health through using stairs regularly.
  • 6 Improve Kitchen Processes to reduce Energy Use. Energy consumption of commercial kitchens could be reduced by optimising the usage for the most effective and efficient output. Revisiting oven preheat time, cooking temperature settings, just in time supply of frozen foods to reduce refrigerated storage mass, week end reduction of logistics supply, optimizing the menu spread etc.
  • 7 Reducing solar heat gain and loss. By controlling the radiated heat entering the premise during summers and losing the stored heat within the room in winters through installation of double glazed windows, sunscreen films, textile drapes, vertical or horizontal blinds etc.
  • 8 Reduce Air Conditioning (Cooling) Costs During Cooler Months. Use the cooler fresh air to cool the building interiors. High dust or hazardous environments may hamper this initiative.
  • 9 Increase Space Temperature in Summer. By increasing the space temperature within the buildings, the occupants are not likely to make out the difference much since the temperature differential compared to external ambient air is high. This is applicable to non critical comfort AC spaces only.
  • 10 Reduce overall fresh water consumption. Reduced use of water would indirectly reduce the energy cost of water processing, pumping and grey water treatment costs.

Emergency Responses – Part 4 – Wall Collapse

Scenario 3 – A wall collapse

One of our premises was adjacent to a large construction site. There was a thick and high old wall separating the two plots. Over a weekend, the construction company next door excavated large volume of wet mud and stored it in the open ground on the other side of the wall. To gain maximum space, the wet mud was pushed on to the wall. Over the week-end, the wall got soaked, became soggy, could not take the load of the wet mud mass leaning on it and collapsed, bringing down a few fully grown trees with it. Parts of the wall and the tree branches penetrated the building at various points including couple of fire-proof doors, a few windows and ventilators.

A package AC out-door unit servicing the UPS room was crushed under the debris. The incident occurred on a Sunday at the stroke of midnight, during the hot summer months in Chennai. Since it happened at the stroke of midnight, there were no casualties. The security guard who had just walked past the location was the only eyewitness of the collapse and was in shock, since he had passed the area a just few seconds before the incident.

During normal working hours, there are cars parked parallel to the building and people used to come out for fresh air and used to sit underneath the trees.

The consequential problems were more pronounced than the actual structural damage to the building. The UPS room located in the basement lost its air-conditioning. Due to extreme heat, the batteries lost its charge retaining time – normally 30 minutes back up at 80% load. During one of the power outages, two gensets did not start in auto mode. By the time the gensets were started in manual mode, the UPS batteries got discharged and the data center in one of the floors was affected due to UPS power outage.

Root Cause for wall collapse.  The wall collapse was triggered by the storing wet mud on the other side. This was beyond control of the site FM team.

Root Cause for UPS Battery Failure.  Rise in room temperature had reduced the charge retention time, thus reducing the effective back up time.

Root Cause of incident leading to UPS Battery Drain.  Two of the three gensets had problems in auto starting, but were not highlighted, no log entries made, nor repair actions initiated. The duty technicians were not briefed on emergency actions on gensets and the urgency in taking them on load, to avoid UPS battery discharging – a special condition at that point of time.

 Actions taken to avoid recurrence

  • Regular monitoring of construction activities in the adjacent plots.
  • Writing down and practicing Genset emergency start operations to reduce elapsed time.
  • Educating the Duty Technicians about the importance of keeping the Log Books and other Information Boards up-to-date.
  • Educating all the duty staff on the importance of complete handing over and taking over of duties and shift briefing by the shift supervisors.
  • Educating the technical staff about the effect of high temperature on UPS and UPS Battery bank performance.

Complacency is a major threat to emergency preparedness. Regular briefing and planned mock drills with full participation of all stake holders would help in reducing the impact of emergencies.

Hope that all the readers enjoyed this series on emergencies and disaster management, covered in four parts.

Kaycee

Mobile or Portable or Spot Cooling Solutions

Hi all,

In many of our sites we face some crises caused by faulty HVAC systems leading to servers crashing, control circuits failing, critical operations coming to a grinding halt etc.

We are used to Window type ACs, Split ACs, Split ductable ACs, Central chillers of various sizes and types.

Take a case of critical server rooms that are very sensitive to both temperature and humidity. With the server technology moving at break neck speeds, each server upgrade reduces its footprint, but increases the heat load many fold. In most cases, server upgrades take place in bits and pieces with only the obsolete machines being replaced. This adds to the woes of the infrastructure maintainers.

The replacement servers are normally heat spewing monsters and cause hot spots in the server rooms. The infrastructure maintainers run helter-skelter to control the situation, but most of the time fail to achieve ideal conditions.

Recently I happened to read a few articles and papers regarding mobile / portable / spot cooling AC solutions. I also happened to visit the website of one of the product suppliers specialising in such solutions.  The linked web page has many other links from which you can get further details.

http://www.movincool.com/

Kaycee

Energy Conservation and incentives

Hi all,

The linked article is more towards the legal aspects of energy conservation, but as infrastructure maintenance professionals, we need to read between the lines to understand how all we could conserve energy.

Waste heat recovery is definitely a less travelled path in older facilities. We waste much energy through heat exchangers and cooling towers. The amount of heat thus wasted could have been fruitfully used elsewhere.

The article will definitely provide food for your thoughts.

Energy incentives are a win-win for new plants
Energy Expert, Peter Garforth says break the heat recovery paradox and replace tax breaks with energy incentives.

Kaycee