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Sharpen Maintenance Estimates: Knowing How to See

Posted: November 22, 2016 | Blog

Planning and estimating maintenance jobs requires consideration of all material, labor and supervision necessary to complete a safe, high-quality, and thorough job. The sequence of every job follows the same steps: preparation, travel to and from the job, work content at the job site, and cleanup and put-away. A good, all-inclusive job estimate accounts for the time involved in all these steps.

Field Check. Prior to the job start, a planner does a field check at the job site. This step can involve speaking with the person requesting the work to make sure their scope of work and needs are met. At the job site, the estimator should prepare a job plan containing four parts: the work plan, material plan, special tools and equipment plan, and safety plan. The safety plan is last because it is customized depending on the other three parts of the job. The content of each part of the plan is as follows:

Work Plan. Standards, or “should-take times,” have been applied to maintenance work for decades to aid in answering the age-old questions: “How much work can I assign to my crew?”, “How will I know the crew is performing well?”, “When will the next assignment be needed?”, and “How much work is in the backlog by skill?”

The standard hours for a job are based on work content. Work content is the statement of work  – not the statement of a problem. “Motor doesn’t run” may be the requester’s description. But the estimator’s description will be “remove and replace motor” or “disassemble pump and remove blockage from impeller.”

The determination of the work to be done requires a lot of experience, so the best planners are those who have worked in maintenance, are good at troubleshooting, and know the best tools and procedures for getting the job done. Each description is brief, but contains the essentials of the job – a verb, or action word, a noun – describing what is to be worked on and any descriptive data to clarify what is to be done.

Two essential parts of the work plan are the skill and standard time estimate. The number of workers required for each skill used, and the labor-hours required are based on the work content.

If the job is “remove and replace 30 hp AC motor,” then the time is .75 labor-hours – plus time for preparation and travel. Two electricians are needed, as heavy lifting is required. If the preparation and travel time – from pre-established tables – adds another hour, then total standard hours for the job are 1.75 hours, or about 0.9 hours duration for two electricians.

If the actual time taken was two hours, then performance against the standard was 88% [(1.75/2.00) x 100]. The standard time is an excellent training tool. It tells the supervisor when an apprentice needs more training or has achieved mastery of the job. It also answers all the supervisor’s questions set out above. Delays that hinder the job are revealed and can be reduced as planning improves.

Material Plan. The material plan contains a list of parts and materials required by the job. Each item on the material list includes quantity, size and description (e.g. “(4) C96 V-belts, matched.”) Depending on the part house setup, an inventory number may be required.

Special Tools and Equipment Plan. This part of the plan contains a list of any special tools required that aren’t usually carried in the employee’s tool box – tools that must be drawn from company tool supplies, such as a 1/2-ton come-along, 2-ton chain hoist, or oxy-acetylene welder. To prevent delays, this equipment is reserved in advance so the job start can depend on having the equipment available.

Safety Plan. After all the job elements are planned, the safety issues are considered. Personal protective equipment depends on job site conditions: For example, a hard hat may be required in all areas or only some, depending on the danger of overhead obstacles or falling objects. Other safety equipment includes safety glasses or goggles, gloves, safety shoes, fall protection, welding hoods, air packs, etc. In some confined-space jobs, both air packs and a safety harness must be used, and an outside person must be available to winch the worker out if necessary. Other safety items may include ladder shoes, traffic cones, or fire watch after welding is completed. Permits may be a part of the safety plan – for example, to allow access to restricted areas that are usually kept locked.

The key to good estimates and high productivity is an exact and complete work plan.

Leonardo da Vinci (1452 – 1503), the talented and creative artist who painted the Mona Lisa, was also an engineer and an architect. He conceptualized and sketched technological marvels centuries before their time: the tank, helicopter, calculator, and solar power. Da Vinci taught at a studio in Milan, where he expounded to his art students on “saper vedere” – knowing how to see. He felt that the key to art was in the perspective. He also stated that creativity is knowing how to truly see. Da Vinci believed that altering perspective (viewing a subject from several viewpoints) would help one see and fully understand the subject.

The successful Facility Manager is the modern da Vinci – constantly challenged to imagine ways to achieve optimum maintenance cost and functional objectives … often under difficult time constraints. The cost objective is achieved when a workable budget is completed, funds are approved, actual cost versus budget is maintained, and optimum life cycle cost is closely approached. The functional objective is met when the facility coincides with the design intent, and continuous improvement is institutionalized as a reliable, sustainable way of doing business.

To stay head of all the demands, the Facility Manager uses Predictive Maintenance (PdM), a highly effective method of achieving “saper vedere” when used as an integral part of the annual preventive maintenance program. PdM employs da Vinci’s principle by extending the senses of touch (vibration, temperature), sight (vision, thermal imaging), and trending (rate of change of conditions). These are all examples of how to see each part of the facility from different perspectives. Each of these PdM measures offers a different perspective to improve estimate accuracy, improve understanding, identify optimum repair intervals, and optimize the life cycle of structural, mechanical, and electrical assets. PdM, when done right, uncovers hidden, impending breakdowns before they occur, averts safety and health issues, and curtails expenses caused by catastrophic damage. The result is energy and cost savings, continuous improvement, greater reliability, and the optimization of every budget dollar. Some real life examples of PdM in estimate work are:

Improving HVAC/R Systems. Using a clamp-on ammeter to measure compressor amps; then adding compressor oil and seeing amps drop, electric bills decrease, and compressor life extended. A refrigerant leak detector with the new semi-conductor sensor is very sensitive to small leaks of most refrigerants in use today. Optimum constant temperature and RH is maintained to protect facilities and contents with intelligent thermostats, and temperature and relative humidity recorder-controller to document trends.

Improving Roofs and Exterior Walls. Integrity check inspections using coring, contact moisture meters, and thermal imaging can reveal hidden roof damage – allowing repairs to be done before they are visually obvious, reducing roof maintenance costs and extensive interior damage. If the estimator introduces such simple cautions as soft shoes, using protective walkways, and care in walking or setting equipment on the roof, the crew can avoid punctures that turn into new leaks. Frequently checking roof flashing, joints and seals around penetrations, and resealing them will add years to any roofing system. And frequent use of imaging to locate hidden moisture under the surface will lower costs – avoiding interior damage in walls and above ceilings before major water damage occurs.

Checking the Piping System. Camera inspections, test specimens, and use of flow sub-metering to see where all the water is going are ways “knowing how to see” can save. Some facilities use routine cleaning of all piping on a scheduled basis to keep piping clear; but not all pipelines become blocked at the same rate. Some pipe disassembly is wasted. Also, the frequency may be too often, in which case the cost is higher than needed. And in other cases, the frequency is not often enough, so the piping becomes blocked, interrupting service and costing emergency rates for repair. If the estimator schedules inspections using fiber-optic cable and a camera, the piping can be cleaned at optimum intervals, minimizing unscheduled downtime and cost.

Test specimens are useful for measuring rate of piping wall corrosion and erosion so that replacement can be done at optimum intervals. The technician prepares a specimen of the same material as the pipe wall, threaded on one end and rod-shaped on the other. The diameter of the rod end is measured with a micrometer to the thousandths of an inch. A bushing is welded to the pipe wall at the test location – near an elbow, for example – where erosion is likely. The specimen is threaded into the bushing and remains for a recorded period of time, say a year. At the end of a year, it’s removed and measured. If the original diameter of the machined rod was 0.500 inches and the diameter a year later is 0.400 inches, then the rate of wall loss is 0.100” per year. The years of life are calculated by dividing the original wall thickness –  say 0.250” – by the rate of loss, 0.100”, or two-and-a-half years. This method is far better than the “play-it-safe” approach – changing the pipe before it wears out, or the “take-a-chance” method – letting it fail before replacing it.

Sub-metering water consumption can find leaks and high usage areas early. The estimator can measure the effects of upgrading to low-flow fixtures, and control water cost even when rates are going up.

Checking Electrical Distribution Systems. The electrical distribution system is one of those “out of sight, out of mind” elements of the facility. Distribution system design, motor and control design, and switchgear have benefited from major design improvements over the years. Almost no problems anymore, you say. But wait! What about power outages? What about transformer explosions? Lightning strikes due to faulty insulators and breakers? Relay outages due to overload?

Downtime does occur in the wider infrastructure and inside the facility too. The way to find out if hidden problems are threatening the distribution system is “aper vedere.” You could go around and visually inspect, but you won’t see much out of the ordinary. You could touch motors, controls, conduit, and switchgear looking for hot spots. But a safer, more sensible way to do this is with non-contact thermal imaging.

Improving Energy Efficiency. Lighting upgrades can enhance constant lumen output and improve longevity. Are those incandescent lights costing too much and providing diminishing output over their lives? Are fluorescent lights in the shops, garage, halls, offices, and classrooms humming? Are you having to replace ballasts frequently? You could keep using old technology, but 100- and 75-watt incandescent bulbs and T12 fluorescent tubes, introduced in 1938, are no longer even legally manufactured in the United States.

When supplies are used up, upgrades will be required. Measuring lumen output may indicate significant lighting loss in these old lamps. Switching to LEDs or other high-efficiency lighting will improve the lighting level and life cycle. Also, switching to more efficient lamps will improve function and save many dollars in energy and maintenance costs. LEDs last 50,000 hours or more – that’s five years without changing a bulb – at an energy cost as low as ten percent of incandescent cost for the same lighting level. Induction lighting lasts even longer and gives greater lumens per watt.

Lube Program. Another PdM technique for estimators is facility-wide lube analysis. Using the right lubricant, applied with the right method, at the correct frequency, and in all the right locations, sounds simple. But in fact, a comprehensive lube program requires a lot of careful planning and can be aided by lube analysis, with a lubricant supplier doing an assessment and setting up an annual program.

Vibration Analysis. Blower motors, bearings and drives, pumps, vent fans, generators, turbines, and compressors all have one thing in common – they have rotating elements. Since the 1950s, vibration analysis has been used to predict the remaining life in rotating machines. Measured amplitude and frequency of vibration tell the estimator a lot about the condition and remaining life of a moving part.

Actual vibration amplitude close to the breaking point on a general severity chart means an impending breakdown. The frequency of the high vibration identifies the component. For example, if the high vibration is at a frequency of four times the rotating speed, and the pump has an impeller with four blades, then the impeller is the cause and needs to be rebalanced or replaced to avoid serious damage.

Estimators employ vibration analysis acceptance testing to see how equipment fits the application, ensuring long life for new rotating equipment installations.

Studies show that, if not tested, after five years, fifty percent of circuit breakers do not function normally, primarily due to mechanical problems. With circuit breaker vibration analyzers, estimators perform trip tests, recording and comparing first trip with later trips to identify problems such as spring weakening and excess friction. An accelerometer circuit breaker analyzer app uses the same capability that rotates a smart phone picture from landscape to portrait.

Ultrasound. Facility Managers can apply ultrasound—acoustic emission—analysis to detect high frequency noise inaudible to the human ear. It detects leaks in boilers, condensers, steam and air systems, and other big energy consumers. It is also very effective in detecting electrical discharges such as arcing, tracking and corona. A manufacturer saved nearly $80,000 annually by correcting numerous leaks in the air system after a brief ultrasound inspection. Other uses of ultrasound for the estimator include bearing, lube and machine condition monitoring.

Six Steps to Initiating Predictive Maintenance

Is PdM right for your facility? If you want to find out, have an outside firm run a pilot test on a sample of mission-critical equipment and provide a savings-versus-cost analysis before committing to purchase of PdM analyzers. Once the justification is achieved, selling the program will be easier. If an all-in decision is reached, there is a six-step PdM installation program:

1. select the equipment to include
2. design a history record for each asset as part of the CMMS
3. select PdM analyzer(s)
4. establish measurement intervals as part of the preventive maintenance program
5. initiate readings; record results
6. analyze records for corrective action

Payback for PdM analysis costs have been shown to be very rapid, often less than a year. What is the savings of avoiding even one roof or pipe leak? One electrical transformer fire? One arc flash fire? Knowledge gained allows the maintenance planner to estimate the work based on an accurate assessment of work content. “Saper vedere” makes other costly, unreliable “take-a-chance” or “play-it-safe” strategies not only obsolete, but outlandish. Estimators can now decide what and when to repair, and make repair plans – keeping the facility in A-1 condition, and getting rave reviews from management, employees and visitors alike.