Matching Knowledge and Information
Bailouts, barrels of oil at $150/barrel, boom and bust of the housing markets, wars, elections, and the gloomy global economy have forced hard decisions for many. For example:
1. Rising fuel costs force air lines to get creative and pass the costs to flyers such as charging for food, leg room, checked luggage, and even pulling wires to reduce weight.
2. Even one man's trash is another's treasure. For years, no one wanted sawdust and now it is up to $50/ton to or $1,200 per truck. One may say "we are being forced to get everything out of the pig except the squeal".
These types of external pressures are squeezing all corporate profits, sustainability goals and affecting maintenance organizations which are:
- already thinly staffed with backlogs exceeding available hours;
- very reactionary;
- and relegated to keeping the existing systems as good as possible.
How will you get creative to save money and add back to the bottom line or protect whatever reliability team is still standing? This is difficult since many facility maintenance departments are care takers of older equipment and systems which were not designed for energy conservation.
The Tale of Two Maintenance Leaders
Maintenance Leader #1
Let's pretend you are making the big bucks with few headaches as the Director of Facilities at a large pharmaceutical overseeing a reliability program of 24,000 assets at 10 plants in the eastern U.S. In the last 6 months, over 3,000 positions have vanished and the buzz is that there are more layoffs coming, less overtime and a 15% cost reduction mandate across the board. Forget getting the capital for improvements, you are trying to keep your reliability program staffed and sustaining production.
Where are you going to find some money?
The good news is that in most cases, the energy savings can be found within your existing processes. Your organization has the knowledge to address the issues but may lack the information to pinpoint the cause and implement timely and cost effective repairs.
The great news is that you have a centralized enterprise asset management (EAM) system that will help mine and trend information that can identify systems with the highest probability of providing energy savings. You were told the information is there so it is time to start making this system pay.
A quick search of the EAM platform shows that infrared thermography of your electrical systems has identified 793 temperature anomalies totaling 44,300 oF over OEM heat curves and a potential savings in the next year of $94,3531.
Just like a crime scene investigators, you have followed the clues to find the bad actors. Now that you have the information, applying your knowledge is easy and determines the direction and proactive strategies. Using a rule of thumb that 70% of electrical thermal issues are caused by loose connections cross-referenced with your top 10 components (blue highlights), the list starts to become a little more manageable with 521 items worth $80,000 in savings (blue highlights).
Your plan of action is two fold. Issue work orders to critical systems with connection issues or the highest paybacks and establish a connection torque program during the annual infrared inspections. Successfully eliminating these poor / loose connections eliminates 30,000 oF in excessive temperatures (Bright Yellow Highlights) and the associated fire and safety risks.
If you are lucky, you could pick up more savings by using the EAM platform to cross-tie the next bad actor cause category of internal flaws with "poor connection-related" components already being addressed or near the these systems. You are confident since this energy saving opportunity doesn't include motor systems, compressed air, steam, etc.
Maintenance Leader #2
This is the other guy who represents many and is experiencing the realities of knowledge and information gaps.
Most organizations are in some mode of not having perfect information, trying to add a technology and/or trying to build a critical mass of data. Transforming maintenance into a profit center can be an uphill fight. You may only have one opportunity to mine the asset data / financials to gain management acceptance of reliability programs as a contributor to the bottom line and funding support. If any of these fit your situation, the following steps and calculations can help guide you through typical facility systems, PdM technologies that can identify issues and basic energy saving calculations.
Step 1 - Build an Inventory of Your Assets
It is crucial to gain a complete picture of all assets within a reliability program or at least the equipment targeted in your pilot project. If you are very, very lucky, your computer maintenance management systems (CMMS) may have some or all of this information.
Keep in mind that from an electrical standpoint, many organizations don't breakdown the electrical systems to the component level (i.e. relays, breakers, and lighting panels) and will not show up in the CMMS.
Don't underestimate the challenges of integrating multiple data sources and types. For example, you may have to work through a mix of spreadsheets, PDFs, databases, MS Word documents, and proprietary software and the inconsistencies associated with each.
If you are finding information gaps or at the early stages, roll-up your sleeves, grab a simple facility layout drawing and notebook and walk the facility to capture asset name plate data.
Step 2 - Get the Energy Bill
This step requires work with the Energy Manager to review 2-3 years of bills and energy patterns. If you don't have an energy manger, your utility suppliers can help explain the billing and any calculations. Using the following sample bill and formula, you are working towards some amount per kilowatt hour that can be applied to your calculations2.
Step 3 - Follow the Money to Prioritizing Your Efforts
The challenge for most organizations is determining which systems will provide the biggest payback based upon the specific technologies.
A simple prioritization approach is to divide the gas, electric and oil bills into two usage categories; by building type and use and by equipment types which are common to a variety of process and applications, compressed air, pump and fan systems, etc. Don't get trapped by assuming the highest energy consumers are enough to drive your PdM process. For example, your facility may have hundreds of fractional horsepower motors that cumulatively consume a lot of energy, but the labor, analysis and reporting costs of deploying PdM to each is more than the replacement costs.
Taking the time to consider each asset's criticality and value to the organization can eliminate 20% or more of originally targeted assets. An asset criticality ranking process creates weighted scores based upon probability of failures, failure severities, value impact on associated personnel, systems, buildings and the overall organization.
Ultimately, you end up with a comprehensive site equipment list and corresponding criticality score that can be easily sorted to identify the most critical equipment by asset classification, building, and cost center.
The list will be used to identify which equipment to focus on first with specific maintenance strategies. Equipment having a high ranking will likely have more advanced PdM equipment strategies and analysis performed; whereas equipment having the lowest ranking may have a lower maintenance strategy such as "run-to-failure".
At this point, we will assume that you have completed the energy and criticality prioritization and that the failure modes in the four following facility systems can be monitored with the associated PdM technologies.
Each organization has a different profile. For example, industrials have a higher number of process-related motor loads, pharmaceuticals more HVAC loads and commercial buildings more focus on the electrical, HVAC and roofing systems.
1. Electrical Distribution - Infrared
2. Motor-Driven Systems - Vibration Analysis, Infrared & Motor Circuit Testing
3. Compressed air - Ultrasound
4. Steam - Ultrasound and Infrared
Remember, you have limited number of attempts to gain or keep support so make sure you are focusing those items with the best probability of showing savings. The intent of the following examples are to provide basic calculations to establish the concept and "ball park figures" for electrical and steam energy savings which will peak enough interest to get you a seat at the "funding table".
Electrical Savings
The key process requires capturing power consumption measurements taken before and after placing a piece of three-phase equipment is put back into service. The two-step process is as follows:
1. Power Calculations
kW = volts x amps x pf x 1.732
1000
- kW - kilowatt
- Volts - voltage used in the application
- Amps - difference in amperage (before - after)
- pf - power factor
- 1000 - takes the total watts and by dividing makes it kilowatts
- 1.732 - square root of 3 for 3 phase power. Eliminate this number for single phase systems.
4.2 = average number of cfm/break horsepower (bhp). This is based on manufacturers' equipment data
2. Annual Savings
Once the kW is determined a second formula is required to determine the annual savings:
Annual Savings = hrs x kW x cost / kW
Energy Saving Assumptions for Calculations:
- Hours of Operation = 8760
- Cost / kWh = $.08
- Equipment is fully loaded
- Motor Efficiency Factor = .90
- Power Factor = .87
- 100 Horsepower Motor
- Average power requirement in kW / brake horsepower (bhp) to generate one bhp = 0.746
Compressed Air Pressure = 100 PSIG
Steam Savings
Steam calculations requirements go beyond the intent of this paper due to collecting numerous items such as boiler efficiency, loading, losses, number of boilers, fuel cost per 1,000 BTU, steam pressures, water treatment chemical costs, labor burden, etc. Depending upon the size of your facility, the boiler plant team will have the cost per 1,000 pounds of steam. The facility energy manager or the boiler manufacturer can help. This paper assumes a cost of $12 per 1,000 pounds of steam.
Opportunity #1: Electrical Distribution
Electricity and electrical distribution systems are the backbone of how we live and what drives most of our nation's progress. The issue at hand is that much of the nation's electrical generation and distribution systems are over 60 years old. Many have surpassed their designed life and more susceptible with safety and supply variables.
These power issues, such as the following, are often hidden and problematic to equipment:
- Unstable utility supply / line surges
- Lightning strikes / transient voltage
- Unbalanced and overloaded transformer bank
- Short circuits
- Unidentified single-phase ground faults
- Faulty power factor correction equipment
- Your browser may not support display of this image.Expertise and staffing shortages
These variables are often hidden but can manifest themselves as single phasing, shorted windings, overheated transformer banks and partially tripped over current protection.
The Risk and Insurance Perspective
Zurich Insurance Risk Engineering reports identify that 30% of all large fire losses are caused by electrical failures (includes all cases and unknown). Graphic 1 breaks down these failures to the component level and shows the percentage of electrical losses caused by lack of maintenance.
Your browser may not support display of this image.
IR thermography captures thermal anomalies and variances in temperatures. It is ideal for capturing high resistance, overloaded, phase imbalance and loose electrical connections that cause overheating and waste energy. Use infrared thermography and the asset inventory, created using steps 1-3 as a road map to scan your high priority transformers, switch gear, disconnects, distribution panels and contactors, relays, breakers, etc Scan while equipment is under load and hit critical transformers / connections during high temperature periods.
Electrical Infrared Survey
Assume that during your infrared survey, a 480 volt, three-phase breaker is found to be operating at a temperature of 171 oF (Graphic 2). The measured ambient temperature is 73 oF. The breaker is rated at 100 amps but the actual load is measured at 38 amps. The anomaly is determined to be a loose connection and requires cleaning and tightening to be returned to a precise state.
Numerous ways exist to calculate the cause/effects of the higher temperatures and energy being wasted (i.e. heat curves, amp draw differences, and voltage drop). The Your browser may not support display of this image.following example uses the amp draw difference between pre- and post-repair amp readings. In this case, the amps before were 38 and amps after the successful repair were 35.5 with a resulting difference of 2.5 amps.
Potential Annual Savings by repairing the loose connection:
kW = (480 volts x 2.5 x .87 x 1.732) / 1,000 = 1.808
= 8,760 x 1.808 x $0.08
= $1,267.38
Opportunity #2: Motor-Driven Systems
In the U.S., motor-driven systems such as pumps, compressors, and materials processors (i.e. grinders, mixers, crushers, sizers, etc.) consume an average of 63% of the electricity in the industrial sector3.
Graphic 3 identifies how this segment is broken down by energy use which can provide some prioritization of your energy efforts4. There are many opportunities since many sites have to live with low cost purchasing practices or older, less efficient motors but there is room for improvement. For example, an older 100 HP with low efficiencies (Pre-EPAct of 1992) costs approximately $35,000 per year and $525,000 for 15 years in energy costs. A staggering 95% of this motor's life cycle costs (LCC) is consumed by electrical costs so reclaiming just a few efficiency points with PdM can add significant savings to your bottom line5.
Motors are rated by class for their maximum operating temperature. Aside from vibration, moisture, chemicals, voltage irregularities, dirt, and other non-temperature related life-shortening items; heat is probably the biggest insulation killer. Temperatures in excess of these maximum ratings will cause damage to insulation on the windings, greatly shorting the life of the motor. For example, for an 18oF (10oC) rise in temperature beyond rated design, the heat reduces insulation resistance and useful life by 50%. Motors can have hundreds of electrical connections that can become loose or faulty because of unexpected thermal expansion6.
Mechanical Infrared Survey
Using infrared thermography, your team scans motors, pumps, compressors and looking for temperature changes / hot spots amongst motors, bearings, couplings, etc. The team identifies a motor-pump unit running 50 oF hotter than comparative systems.
The following identifies two different troubleshooting cases and the associated calculations:
Troubleshooting Scenario #1 - The analysis determines that one phase (leg) of a fully loaded 100 hp motor is 95oF higher than the other two phases. The hotter leg is drawing 45 amps while the others are at 30 amps each. Using the prescribed calculations, this 15 amp differential is wasting $5,045 annually.
Troubleshooting Scenario #2 - A voltage analysis identifies an imbalance of 466, 458 and 445. The following formula helps us determine that the voltage imbalance is 2.5%.
(Average voltage - Lowest voltage) = 456 - 445 = 2.5%
Average voltage 456
Table 3 identifies that this 2.5% imbalance reduces the motor's optimal efficiency by 1.4%.
Table 3: Motor Efficiency under Conditions of Voltage Unbalance
Use the following formula to calculate the motor efficiencies and associated costs of the nominal 94.4% efficiency verses imbalanced 93% efficiency.
(Motor hp) (0.746) x (Annual Hours of Operation) x ($/kW)
Motor Efficiency
Subtracting the two numbers generates an annual savings of $832.98 by working to balance the voltages.
Opportunity #3: Motor-Driven Compressed Air Systems
Compressed air often viewed as the 5th utility, accounts for a significant percent of the energy consumption and can have efficiencies as low as 10-20%. This opportunity involves the optimization of motor-driven compressed air systems by implementing a leak management program which ultimately reduces demand and run time on compressorsYour browser may not support display of this image.. Many organizations are able to shut down an entire compressor and the associate supply-side costs by resolving leaks identified from a survey. Ultrasound technology picks up sound waves above 20 kHz (beyond human hearing). The detector picks up ultrasounds and converts them into an audible range for the operator who is listening with headphones.
Compressed Air Survey
Before you start your compressed air leak management program, it is recommended to determine the best route with a facility drawing or a simple sketch of the compressed air system. Breaking down the system into inspection zones makes the process more manageable. Start at the compressor (i.e. air end) and work outward. Hang a tag at each leak and update your drawing. Make sure you capture the following information to streamline the project and work order ranking process:
- Decibel (dB) levels
- Instrument used
- Number of inches or feet away from the leak when identified
- Take a picture of the location.
During the inspection, look for and tag leak indicators such as valves left open, rags over pipes to reduce noise on large leaks, unattended machines left on and blowing air. Check and repair drain traps and don't leave them cracked open. Check for defective end-use tools and quick connects.
During the survey of your 100 PSIG system, you identify 20 leaks equally split between 20 and 30 dB. Use the following shortened look-up decibel and air loss table and calculation to calculate the cfm losses at each decibel level.
Table 4: Example table of decibel (dB) and system pressures (PSIG)
Values are in cfm based upon air
Energy Savings = (Air Loss (cfm) / 4.2) (0.746) (Annual Hours) ($ / kWh)
Motor Efficiency
These leaks are wasting $3,096 energy dollars annually.
Opportunity #4: Steam Trap Programs
Within steam systems are two types of leaks; internally when a trap fails and steam leaking externally to atmosphere. This energy saving scenario will focus on the trap losses.
Traps are mechanical valves that return condensate back to the boiler for reuse. Failed traps either fail closed or open. A trap failed in the closed position not only reduces efficiency but prevents return of the condensed water vapor only to sit and corrode pipe/components. Safety becomes a concern with slugs of the sitting water being picked up with the live steam creating water hammer. Water hammer can blow apart piping systems exposing personnel and impacting facility services. A trap failed in the open position sends steam back to the condensate tank preventing useful work.
Steam can be a very expensive resource ranging from $5 - $15 / 1,000 pounds of steam which includes the boiler fuel costs, losses, labor, water treatment, etc.
Rule of Thumb for number of Traps Blowing Live Steam
* 50% if no steam trap survey or maintenance program
* 25% with annual program
* 12% with semi-annual program
* Even newer systems can have failed or failing traps as high as 30% within the first 3-5 years.
Steam Trap Survey
A steam trap survey differs from compressed air surveys by requiring a contact probe to touch each trap to check each trap's performance. During your steam trap survey, perform listening and visual inspections, similar to compressed air surveys, to help find steam discharging from valves and fittings, and leak indicators such as rust, corrosion, hissing, rags covering loud leaks, etc.
Add up all losses by multiply the steam loss per trap (i.e. losses typically provided by the equipment manufacturer) by hours of operation, steam cost, and by the number of failed traps and/or piping leaks. Some facilities can have thousands of traps!
Your browser may not support display of this image.In this example, ultrasound and thermography identify a failed trap blowing 100 PSI blowing through with a 3/16" orifice (See following graphic for example of how the dual technologies support a final recommendation). Using the following look-up tables and calculations, one can find the amount of wasted steam and financial impact.
- 97.7 pounds of wasted steam per hour
- Average cost of $12 / 1,000 lbs steam
- $28.14 / day (24 hours)
- $10,270.22 / year (8,760 hours)
Table 5: Steam flow (lbs/hr) through orifices at specific steam pressures:
The US DOE has numerous steam system optimization resources, larger look-up tables and additional calculations supporting the tables.
KISS (Keep It Super-Simple) Principle of Date Management
The challenge for many is that PdM programs generate an enormous amount of data. Much of this is delivered in word processing documents, PDFs and spreadsheets, proprietary software and hard copies which slow a Leader's ability extract information for making empowered and proactive decisions.
If you have good data in a CMMS or an enterprise asset management (EAM) system, use them. On the other hand, don't blinded by their bells and whistles and effort required to input and extract information. Even if you are like Maintenance Leader #1 and have robust software platforms and "mountains" of data, these systems create a belief that "we must wait for the software to kick out perfect information before making a decision".
Additionally, many times the information that would empower a "closed-loop", PdM-to-repair process is missing on the back end of these systems. Chalk it up to human nature or culture, once the repair has been made, the "after repair" information, which is needed for some of your energy calculations, never makes it back into the CMMS or EAM. It is perceived as a waste of time or of less value compared to the interesting wrench time on the next work order and ultimately the data never documented.
Today's recessionary pressures prevent many maintenance leaders from affording this software luxury and or the possible stagnation of efforts. Instead they should rely on "keeping it super simple", small, accurate and manageable. Remember this is a pilot project and in the early stages the approach requires building a case for targeted equipment opportunities with the best and highest probability success. MS Excel can keep collection and centralization to a simple, consistent and manageable level for you, or the utility or service providers providing information. Maintaining the data in a centralized and organized system is crucial for transforming it into usable information which drives the program's success.
Take matters into your own hands. By this, I mean taking a personal stake in collecting the field data and pre- and post-repair readings. This is your project and you may have to overcome cultural barriers, lack of support, manpower shortages and will "trust but verify" the information being collected. Being in touch with the process and validating the results will fuel your passion for the final presentation and closing the deal.
Closing the Deal
As mentioned earlier, most organizations have the knowledge and skills but lack the information to make the right decisions in a timely manner. Once you have solid results, your goal is to provide simple communications that gain support for your reliability and energy saving efforts.
This paper's examples are based upon actual client data which totaled nearly $20,000 in annual potential savings (Table 6). "Potential" is used since someone must implement repairs but it may have to be with little or no capital support. The good news is that the hot and loose electrical connections and compressed air fittings could be addressed with minimal labor and material investment. Even the material cost of purchasing a new steam trap is only a few hundred dollars.
Table 6: Example Energy Savings with PdM
The results are only scratching the surface as the total savings are based upon your equipment population, completeness and frequencies data collections with any existing programs and the wealth of additional energy saving opportunities with additional PdM technologies such as vibration monitoring/alignment strategies, motor circuit and motor current analysis, lube oil analysis/optimization, and aerial infrared surveys for roof moisture saturation.
The first recommendation is to centralized information which is easily accessed, extracted and understood which can be done in a simple spreadsheet or database or with off the shelf packages. Secondly, learn how to "blow your own horn" to gain support for your initiatives by publishing a regular savings and energy report. The message should be financially based, kept simple, and not too technical with numerous discussions and calculations about gallons, kilowatts and amperages. Typical financial calculations cover return on investment (ROI) and/or net present value. When performing the calculations, don't get caught in the trap of only talking about the savings and ignoring the cost to perform the in-house or third-party surveys. Basically, keep in mind that "you have to spend money to make money".
Be specific in your arguments or requests and always have backup documentation in order to support your savings, trend results and to put a scale to the benefits / costs. In addition to the previous energy wasted and now being saved, calculate the corporate financial benefit such as the cost of downtime avoided. The medium could be a few PowerPoint slides or a spreadsheet.
Don't give up. Many, very successful energy programs started with 1-2 small victories and incrementally added successes to overcome skepticism, cultural bias towards maintenances, and lack of awareness.
Regardless of your reliability program's sophistication, this document highlights that the use of simple PdM tools which can recapture lost energy or help you correctly account for its impact to the bottom line and gain credibility for your maintenance team.
Good luck and don't hesitate to call if you need help.
Dale P. Smith, CMRP
Tel: 216.378.3500 x135
Corporate Programs Manager
Predictive Service
Mr. Smith has over 18 years of experience within the engineering and reliability consulting industries designing, implementing and running successful multi-site corporate safety, reliability and energy programs for medium, large and Fortune 500 companies such as Alcoa, General Motors, Kaiser Aluminum, ADM, Schering-Plough and Wyeth.
Mr. Smith formerly served as a Programs Manager for an engineering consulting and safety services firm and managed combustion system safety and asset reliability programs with three global automotive, aluminum and pharmaceutical clients. These clients represented over 300 facilities worldwide. He was the single-point-accountable (SPA) manager responsible for the day-to-day operations, corporate relationships, training, program efficiencies, overall contract administration and profitability.
Projects at Predictive Service include overseeing the development, management and growth of reliability programs for over 15,000 production assets and ensuring that the clients achieve the most cost effective, reliable, safe and competitive facility capacity.
Mr. Smith is a Certified Maintenance and Reliability Professional (CMRP) through the Society for Maintenance and Reliability Professionals (SMRP) and an active member in the Association of Maintenance Professionals (AMP). He is a Corporate Programs Manager with Predictive Service in Beachwood, OH.
Predictive Service (PSC) headquartered in Cleveland, Ohio provides a fully integrated mix of predictive maintenance (PdM) technologies and delivers all information via a centralized, web-based software management system, ViewPoint. PSC helps all types of global corporations ensure reliable, safe, cost effective and sustainable facility capacity. Keep the following services in mind for "safeguarding your future":
o Reliability Engineering
o Electrical and Mechanical Infrared (IR)
o Aerial IR
o Vibration Analysis
o Oil Analysis (lube / Transformer)
o Ultrasound
o Motor Circuit Testing
o ViewPoint - Web-based asset management reporting software