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318

2:49 am
July 2, 2004
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Creating Reliable Equipment Information

Deficiencies in the integrity of equipment data and difficulties in accessing this data are costing asset-intensive companies millions of dollars a year in equipment downtime and business inefficiencies. Waste in the work management processes appears in the form of extended searches for parts and materials; wasted effort due to missing, inaccurate or out-of-date equipment data; procurement errors; and an inability to easily access data from a reliable source.

The result can be expensive to these organizations. Consider the story of a feed pump that was taken out of service, repaired, and stored as a spare. A few months later, the feed pump was reinstalled and capacity dropped by nearly 25 percent. What happened? The maintenance staff did not have access to the current version of the equipment specification showing that the impeller had been modified. The cost of that single incident was about $1 million.

Decades of equipment maintenance and modifications, the gradual degradation of equipment drawings and documentation, and aging plants with old, one-of-a-kind equipment components have contributed to an equipment data problem of severe magnitude. Considering that there are thousands of pieces of critical production equipment in each plant, and multiple documents for each piece of critical equipment, the sheer magnitude of the asset data management dilemma quickly becomes evident.

Information for 10,000 assets
Increasingly, plants are tackling this problem with new tools and processes. The Chevron Products Co. refinery located in Pascagoula, MS, recently undertook a project to re-establish equipment information integrity for all of its rotating equipment—nearly 10,000 assets.

Project objectives were to capture unique equipment nameplate data; photograph all equipment, parts, and spares; construct intelligent bills of material diagrams; scan and organize engineering drawings and operations and maintenance manuals; associate all of the content to discrete assets; and improve the accessibility of the data through a set of visual tools designed for the shop floor worker. The final objective was to upload the validated and relevant content to the enterprise asset management (EAM) system.

The project involved Asset Content Management (ACM) software provided by NRX Global Corp., Toronto, ON, and field engineering support provided by Black & Veatch, a global engineering, consulting, and construction company. The software solution and methodology enables organizations to create, improve, and efficiently manage asset-related information—both paper-based and electronic. It transforms unstructured data into structured and transactable information by visually associating equipment to material items and to documentation, creating what NRX calls Visual Bills of Materials (Visual BOMs).

The process consists of a series of activities that cost-effectively and efficiently support collecting and organizing equipment and material data, collecting the content associated with the equipment, assessing the content, and converting the content into structured information. The final activity is to electronically link each piece of validated documentation and material to the respective equipment, all within a plant-specific hierarchy.

Project goes quickly
“It all has to happen quickly,” said Andy Carroll, Black & Veatch project manager. “Each of these types of projects is unique depending on the business drivers of the initiative. One component that remains constant is the need to execute the project as quickly as possible. Collecting equipment data is a moving target. It’s what gets us into trouble in the first place. The process changes or a project concludes, and then we move on before the new configuration is fully documented or materials data is updated.

“Without efficient, proven work processes for validating equipment and parts data, followed by effective management of the ongoing changes, project managers would be swamped collecting asset data on thousands of pieces of equipment. The application allowed my teams to capture tremendous amounts of parts and equipment data and photograph each one, all validated and organized with minimal post-collection processing or second guessing,” Carroll said.

Industry research repeatedly confirms that maintenance specialists spend 2-3 hours per day “chasing parts.” For instance, the specialist may be investigating new strategies to transition from reactive maintenance practices to a predictive program. If so, reaffirming the role of the maintenance engineer, planner, and technician is critical. Increasing wrench time by providing high confidence information reduces backlog, reduces waste, and increases ordering accuracy. For the manager of a process or production facility that employs hundreds of maintenance specialists, the opportunity for savings is tremendous.

EAM, DMS roles
Solving the problem of quickly locating high confidence maintenance information has been approached through various EAM and document management systems (DMS). An EAM system provides modules for managing and automating maintenance and materials management and procurement processes. They are mostly data-driven, even though the maintenance worker benefits more from a visual experience. DMS systems are a necessary component of a responsible configuration control strategy, but are often no more than a directory structure of cryptic file names without any functional links to the equipment they represent.

EAM software does not come with the equipment, parts, or document content and often, when new systems are loaded with content, provide inaccurate and unreliable information little better than the low-value database that sourced it. This leaves maintenance professionals chasing information in the same manner as they always have: uncontrolled copies of favorite drawings stashed in the bottom drawer; uncontrolled and unorganized document storage rooms; unstructured DMS data; and buried maintenance data in systems with poor user interfaces that lack visual resources.

Brian Moore, project manager at NRX, said: “In the past decade the functional depth of EAM applications has improved dramatically to accommodate most business processes. However, usability and data confidence issues have precluded the plant floor users from adopting the solutions into their daily work regimen, clearly an indication that the return on investment for these applications has not been fully realized.” He goes on to note, “What are the options? Start over? Some have, and some have failed again. Instead, there is a compelling case for revisiting the original goals that drove the EAM investment, and determining which incremental additional investments can move the user closest to the intended goal, or at least provide a justifiable incremental value-add.”

An earlier article—“Building a Plant Asset Information Database” —discussed the plan of Interstate Power & Light’s Burlington Generating Station, Burlington, IA, to have high data integrity from the onset of its CMMS implementation. MT


Information supplied by Andy Carroll and Brian Moore. At the time of writing, Carroll was manager of Black & Veatch Corp.’s Plant Asset Management group, Overland Park, KS; (913) 706-5912 . Moore is a project manager at NRX Global Corp., Toronto, ON; (877) 603-4679

0704bvfig1

More than a parts list, the Visual BOM links equipment, parts, photographs, drawings, and manuals.

0704bvfig2

The project converted 52,151 images (or a 25-ft stack of paper) and 3576 drawings, digitized 3766 parts lists,
and matched 95,194 BOM line items to discrete equipment.

back to article Continue Reading →

160

2:47 am
July 2, 2004
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Maintenance Information Systems

Directory of EAM/CMMS software for maintenance and reliability organizations.

Enterprise asset management (EAM) and computerized maintenance management systems (CMMS) are essential to most maintenance and reliability strategies irrespective of plant size. The software must manage and optimize reliability and performance of plant physical assets and maintenance operations, support a company’s business process, and be tied in to business drivers. It must support a company’s overall asset management strategy.

Buying decisions begin with an analysis of how a maintenance organization operates today and what its strategy is for the future. These systems can help organizations implement their strategy to decrease downtime and increase the utilization of their resources, and can be viewed as a communication tool to help make better decisions. Software can help companies improve their business but no program will do everything the way users want it to, so compromises will need to be made.

Maintenance information systems run on multi-platforms using mainframe, client/server, thin client, or browser-based applications. Smaller, stand-alone systems run on PCs or local area networks. Because some powerful packages can run on a single PC or networked PCs without a midrange server, the dividing line between small and large systems has blurred. Therefore, we are including all software packages in one directory.

Many companies offer programs specifically built to be accessed across the Internet. These web-architected programs enable rapid deployment across a number of sites using a Web browser and established wide and local area networks. Multi-site organizations can benefit from a centralized data repository which allows for normalization and standardization across plants. Another variation of this method lets users access the program through the Internet but the data resides in their own plants

Using these approaches, maintenance personnel can access information and work orders in a number of ways—dedicated terminals and PCs, or mobile Palm-type personal digital assistants (PDAs) and handheld computers running Windows CE. Other wireless and radio frequency devices to access information are also at hand. Developments including e-commerce, supply chain integration, the Internet, and wireless technologies that first were implemented in larger plants also are benefiting smaller and midsize plants.

Some companies offer an application service provider (ASP) option to their programs. Users pay a monthly per-seat fee to access the software through an Internet-enabled workstation. The ASP stores the program and the data on its server. Users always have access to the most current version of the program. This delivery method eliminates the need for on-site hardware infrastructure, system administration, and associated costs at the user’s end and lets companies concentrate on operating their plants rather than their computer systems.

To meet the needs of the increasing number of companies that recognize the benefits of electronic transactions, some software suppliers provide web-enabled systems that support e-procurement within their own program or allow users to integrate their EAM or CMMS system with other vendor software. Another growing area is connectivity with programs having the ability to integrate with other plant ERP business applications, production automation systems, and other software in the plant.

Information in the listings includes the company contact information, software titiles, and general information about the application’s architecture, operating system, and underlying database.

The database manager is a significant contributor to the performance of an EAM/CMMS. It handles procedures that otherwise would have to be written into the application software, adding to its complexity. Many EAM/CMMS programs are written to run with a variety of databases. Other programs are written for a single database, which allows them to make better use of the features and development tools provided by the database. ODBC indicates compliance with Open Database Connectivity, an SQL-based interface from Microsoft designed for consistent access to a variety of databases.

Information for the directory was directly provided by suppliers who are actively promoting their products. MT

 

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219

2:19 am
July 2, 2004
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Online Privacy: Send the Spies Packing

Do you ever get the feeling someone is watching you? If you spend much time surfing the Internet, it is quite possible that someone is watching you, or at least watching your online behavior.

Some companies secretly install software on your computer system that tracks what Web sites you go to under the theory they can guess what you might like to purchase in the future. That information is deemed very valuable by marketers. Depending on your browser and firewall security settings, you may unknowingly let this tracking software get installed by visiting a Web site or by downloading some type of file-sharing software. Almost all free file-sharing software downloads include tracking software. This software is sometimes referred to as spyware.

According to Steve Gibson of Gibson Research Corp., spyware is any software which employs a user’s Internet connection in the background (the so-called “backchannel”) without his knowledge or explicit permission. Silent background use of an Internet backchannel connection must be preceded by a complete and truthful disclosure of proposed backchannel usage, followed by the receipt of explicit, informed consent for such use. Any software communicating across the Internet absent these elements is guilty of information theft and is properly and rightfully termed spyware.

How do you know if your PC is spying on you? If you have a teenager at home and you have heard him or her talk about downloading music, you have spyware on your PC.

Luckily there are plenty of good software programs to scan for any spyware that may be on your computer. These programs also can help you eliminate spyware from your system and prevent it from returning. The most popular is a free download (premium versions are also available) called Ad-aware from LavaSoft. With over 45 million downloads and rave reviews from all the PC magazines, it seems to be the clear favorite.

Another way to avoid spyware is to check the software that you are about to download against the list of known spyware carriers at Spyware-Guide.com

How big is the spyware problem? So big that the U.S. Federal Trade Commission (FTC) hosted a one-day public workshop on spyware issues in Washington, DC, in April. The issues the FTC deals with touch on the economic lives of most Americans, where the FTC works to ensure that U.S. markets are free of restrictions that harm consumers and enforces federal consumer protection laws that prevent fraud, deception, and unfair business practices.

Before you panic, some cookies (that track your return visits) can actually be considered spyware, but most companies state that they do not collect individually identifiable information about a Web surfer. The factors that enter into a decision to trust that company and its privacy policy are the same as you would use in the physical world. Certainly avoid filling out forms on Web sites that do not publish a privacy policy.

In addition, our privacy is slowly eroding in the real world also as more and more video surveillance cameras are being installed. The United Kingdom already has placed more than 2 million cameras throughout its countries. This model has caught the attention of almost all major metropolitan police departments that are beginning similar programs throughout the U.S. No antispyware I know of will remove those privacy invaders.

You can learn much more about all kinds of online and offline privacy issues at the Electronic Privacy Information Center. MT

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6834

1:12 am
July 2, 2004
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Temperature Monitoring Is Key To Motor Reliability

Regularly checking the operating temperature of each critical motor will pay dividends.

It is no secret that heat kills electric motors. But it is easy to forget that exceeding the rated operating temperature by as little as 10 C (18 F) can shorten the life of a three-phase induction motor by half.

The first step to prevent unexpected shutdowns and extend motor life is to determine the temperature rating of the motor. The National Electrical Manufacturers Association (NEMA) defines this rating for three-phase induction motors in its standard Motors and Generators, MG 1-2003. Temperature rating also can be found on the motor’s original nameplate. Once the temperature rating is known, the temperature rise can be measured directly using sensors or an infrared temperature detector, or indirectly using the resistance method.

Key terms
Ambient temperature is the temperature of the air (or other cooling medium) that surrounds the motor. The difference between the ambient temperature and that of a motor operating under load is the temperature rise (temperature rise = hot temperature – ambient temperature).

NEMA rates insulation according to its ability to withstand overall temperature. For example, a Class B insulation system is rated 130 C, while a Class F system is rated 180 C. Since the maximum ambient temperature according to NEMA MG 1-2003 is normally 40 C, one would expect the temperature rise limit for a Class B system to be 90 C (130 C – 40 C). But NEMA also builds in a safety factor, primarily to account for hot spots—i.e., parts of the motor winding that may be hotter than the location at which the temperature is measured. See Fig. 1.

Table 1 shows the temperature rise limits for NEMA medium electric motors based on a maximum ambient temperature of 40 C. In the most common speed ratings, the NEMA designation of medium motors includes ratings of 1/2–500 hp for 2- and 4-pole machines, and up to 350 hp for 6-pole machines.

Temperature rise limits for large motors—i.e., those above medium motor ratings—differ based on the service factor (SF). Table 2 lists the temperature rise for motors with a 1.0 SF; Table 3 applies to motors with 1.15 SF.

Resistance method
The resistance method is useful for determining the temperature rise of motors that do not have embedded detectors—e.g., thermocouples or resistance temperature detectors (RTDs). Note that temperature rise limits for medium motors in Table 1 are based on resistance. The temperature rise of large motors can be measured by the resistance method or by detectors embedded in the windings as indicated in Tables 2 and 3.

To find the temperature rise using the resistance method, measure the lead-to-lead resistance of the line leads with the motor cold—i.e., at room (ambient) temperature. Be sure to record the ambient temperature as well. Then run the motor at rated load long enough for the temperature to stabilize (up to 8 hours sometimes) and measure the hot resistance in the same way.

Plug the cold and hot resistance measurements into the following equation to find the hot temperature then subtract the ambient temperature from the hot temperature to obtain the temperature rise.

Th = [(Rh/Rc ) x (K + Tc) ] – K

where:
Th = hot temperature

Tc = cold temperature

Rh = hot resistance

Rc = cold resistance

K = 234.5 (a constant for copper)

Example: An unencapsulated, open drip-proof medium motor with a Class F winding and a 1.0 service factor has a lead-to-lead resistance of 1.02 ohms at an ambient temperature of 25 C, and a hot resistance of 1.43 ohms. The hot winding temperature would be:

Th = [(1.43/1.02) x (234.5 + 25)] – 234.5 = 129.3 C (round to 129 C)

The temperature rise equals the hot winding temperature minus the ambient temperature, or in this case:

Temperature rise = 129 C – 25 C = 104 C

Notice that the calculated temperature rise of 104 C in the example is just 1 deg below the limit for Class F (105 C) in Table 1. Although that is acceptable, it is important to keep in mind that any increase in load will result in excessive temperature rise and serious thermal degradation of the motor’s insulation system. Further, if the ambient temperature at the motor installation were to go above 25 C, the motor load would have to be reduced to avoid exceeding the machine’s total temperature (hot winding) capability.

Determine temperature rise using detectors
Motors equipped with temperature detectors embedded in the windings are usually monitored by directly reading the output of the detectors with appropriate instrumentation. Typically, the motor control center has panel meters that indicate the temperatures sensed by the detectors.

If the embedded detectors are not connected to the controls, a handheld temperature meter can sense the output of the detector leads while the motor is operating. The output temperature displayed is the hot winding temperature at the location of the sensor. If a handheld temperature detector were to read 129 C as in the example above, the same concerns about the overall temperature would apply.

How do you determine the operating temperature of a motor winding that does not have embedded detectors? For motors rated 600 V or less, it may be possible to open the terminal box (following all applicable safety rules) and access the back of the stator core iron laminations with a thermocouple (see Fig. 2). The stator lamination temperature will not be the same as winding temperature, but it will be closer to it than the temperature of any other readily accessible part of the motor.

If the lamination temperature minus the ambient temperature exceeds the rated temperature rise, it is safe to assume that the winding is also operating beyond its rated temperature. For instance, had the stator core temperature in the above example measured 136 C, the temperature rise for the stator would have been 136 C – 25 C, or 111 C. That exceeds NEMA’s limit of 105 C for the winding, and the winding can be expected to be hotter than the laminations.

The critical limit for the winding is the overall or hot temperature. Again, that is the sum of ambient temperature plus the rise. In large part, the load determines the temperature rise because the winding current increases with load. A large percentage of motor losses and heating (typically 35–40 percent) are due to the winding I2R losses. The “I” in I2R is winding current, and the “R” is winding resistance. Thus the winding losses increase at a rate that varies as the square of the winding current.

Adjusting for ambient
The ambient temperature also may be a factor. If it exceeds NEMA’s usual limit of 40 C, the motor must be derated to keep the total temperature within the overall or hot winding limit. To do so, reduce the temperature rise limit by the same amount that the ambient exceeds 40 C.

For instance, if the ambient is 50 C and the temperature rise limit in Table 1 is 105 C, decrease the temperature rise limit by 10 C (50 C – 40 C ambient difference) to 95 C. This limits the total temperature to the same amount in both cases. That is, 105 C + 40 C = 145 C, and 95 C + 50 C = 145 C.

Regardless of the method used to sense winding temperature, the total or hot spot temperature is the real limit, and the lower, the better. Each 10 C increase in operating temperature shortens motor life by half, so check motors under load regularly. Do not let excessive heat kill motors before their time. MT


Thomas H. Bishop is a technical support specialist at the Electrical Apparatus Service Association (EASA), 1331 Baur Blvd., St. Louis, MO 63132; (314) 993-2220

Shutdown and Alarm Range Based on Insulation Systems

0704easafig1

Fig. 1. Hot spot temperature vs ambient and rise for Class B insulation system. Note that at 40 C ambient (horizontal axis),
the rise is 90 C (vertical axis). The sum of the ambient and temperature rise will always be 130 C for a Class B insulation system.

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0704easafig2

Fig. 2. It may be possible to determine the approximate temperature of the winding with a thermocouple.

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Table 1. Temperature rise by resistance method for medium induction motors based on
a maximum ambient temperature of 40 C

Insulation Class and
Temperature Rise C

Motor Type

A

B

F

H

1

Electric motors with 1.0 service factor (SF) other than those in 3 or 4.

60

80

105

125

2

All electric motors with 1.15 or higher SF

70

90

115

 

3

Totally-enclosed nonventilated electric motors with 1.0 SF

65

85

110

130

4

Electric motors with encapsulated windings and with 1.0 SF, all enclosures

65

85

110

 

(Ref. NEMA MG 1-2003, 12.43).

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Table 2. Temperature rise for large motors with 1.0 service factor at rated load

Insulation Class and
Temperature Rise C

 

Motor Rating

Method of Determination

A

B

F

H

1

All hp (kW) ratings

Resistance

60

80

105

125

2

1500 hp (1120 kW) and less

Embedded detector

70

90

115

140

3

Over 1500 hp (1120 kW) and 7000 V or less

Embedded detector

65

85

110

135

4

Over 1500 hp (1120 kW) and over 7000 V

Embedded detector

60

80

105

125

(Ref.: NEMA MG 1-2003, 20.8.1).

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Table 3. Temperature rise for large motors with 1.15 service factor at rated load

Insulation Class and
Temperature Rise C

Motor Rating

Method of Determination

A

B

F

H

1

All hp (kW) ratings

Resistance

70

90

115

135

2

1500 hp (1120 kW) and less

Embedded detector

80

100

125

150

3

Over 1500 hp (1120 kW) and 7000 V or less

Embedded detector

75

95

120

145

4

Over 1500 hp (1120 kW) and over 7000 V

Embedded detector

70

90

115

135

(Ref.: NEMA MG 1-2003, 20.8.2).

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176

6:18 pm
July 1, 2004
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Creating Reliable Equipment Information

Deficiencies in the integrity of equipment data and difficulties in accessing this data are costing asset-intensive companies millions of dollars a year in equipment downtime and business inefficiencies. Waste in the work management processes appears in the form of extended searches for parts and materials; wasted effort due to missing, inaccurate or out-of-date equipment data; procurement errors; and an inability to easily access data from a reliable source.

The result can be expensive to these organizations. Consider the story of a feed pump that was taken out of service, repaired, and stored as a spare. A few months later, the feed pump was reinstalled and capacity dropped by nearly 25 percent. What happened? The maintenance staff did not have access to the current version of the equipment specification showing that the impeller had been modified. The cost of that single incident was about $1 million.

Decades of equipment maintenance and modifications, the gradual degradation of equipment drawings and documentation, and aging plants with old, one-of-a-kind equipment components have contributed to an equipment data problem of severe magnitude. Considering that there are thousands of pieces of critical production equipment in each plant, and multiple documents for each piece of critical equipment, the sheer magnitude of the asset data management dilemma quickly becomes evident.

Information for 10,000 assets
Increasingly, plants are tackling this problem with new tools and processes. The Chevron Products Co. refinery located in Pascagoula, MS, recently undertook a project to re-establish equipment information integrity for all of its rotating equipment—nearly 10,000 assets.

Project objectives were to capture unique equipment nameplate data; photograph all equipment, parts, and spares; construct intelligent bills of material diagrams; scan and organize engineering drawings and operations and maintenance manuals; associate all of the content to discrete assets; and improve the accessibility of the data through a set of visual tools designed for the shop floor worker. The final objective was to upload the validated and relevant content to the enterprise asset management (EAM) system.

The project involved Asset Content Management (ACM) software provided by NRX Global Corp., Toronto, ON, and field engineering support provided by Black & Veatch, a global engineering, consulting, and construction company. The software solution and methodology enables organizations to create, improve, and efficiently manage asset-related information—both paper-based and electronic. It transforms unstructured data into structured and transactable information by visually associating equipment to material items and to documentation, creating what NRX calls Visual Bills of Materials (Visual BOMs).

The process consists of a series of activities that cost-effectively and efficiently support collecting and organizing equipment and material data, collecting the content associated with the equipment, assessing the content, and converting the content into structured information. The final activity is to electronically link each piece of validated documentation and material to the respective equipment, all within a plant-specific hierarchy.

Project goes quickly
“It all has to happen quickly,” said Andy Carroll, Black & Veatch project manager. “Each of these types of projects is unique depending on the business drivers of the initiative. One component that remains constant is the need to execute the project as quickly as possible. Collecting equipment data is a moving target. It’s what gets us into trouble in the first place. The process changes or a project concludes, and then we move on before the new configuration is fully documented or materials data is updated.

“Without efficient, proven work processes for validating equipment and parts data, followed by effective management of the ongoing changes, project managers would be swamped collecting asset data on thousands of pieces of equipment. The application allowed my teams to capture tremendous amounts of parts and equipment data and photograph each one, all validated and organized with minimal post-collection processing or second guessing,” Carroll said.

Industry research repeatedly confirms that maintenance specialists spend 2-3 hours per day “chasing parts.” For instance, the specialist may be investigating new strategies to transition from reactive maintenance practices to a predictive program. If so, reaffirming the role of the maintenance engineer, planner, and technician is critical. Increasing wrench time by providing high confidence information reduces backlog, reduces waste, and increases ordering accuracy. For the manager of a process or production facility that employs hundreds of maintenance specialists, the opportunity for savings is tremendous.

EAM, DMS roles
Solving the problem of quickly locating high confidence maintenance information has been approached through various EAM and document management systems (DMS). An EAM system provides modules for managing and automating maintenance and materials management and procurement processes. They are mostly data-driven, even though the maintenance worker benefits more from a visual experience. DMS systems are a necessary component of a responsible configuration control strategy, but are often no more than a directory structure of cryptic file names without any functional links to the equipment they represent.

EAM software does not come with the equipment, parts, or document content and often, when new systems are loaded with content, provide inaccurate and unreliable information little better than the low-value database that sourced it. This leaves maintenance professionals chasing information in the same manner as they always have: uncontrolled copies of favorite drawings stashed in the bottom drawer; uncontrolled and unorganized document storage rooms; unstructured DMS data; and buried maintenance data in systems with poor user interfaces that lack visual resources.

Brian Moore, project manager at NRX, said: “In the past decade the functional depth of EAM applications has improved dramatically to accommodate most business processes. However, usability and data confidence issues have precluded the plant floor users from adopting the solutions into their daily work regimen, clearly an indication that the return on investment for these applications has not been fully realized.” He goes on to note, “What are the options? Start over? Some have, and some have failed again. Instead, there is a compelling case for revisiting the original goals that drove the EAM investment, and determining which incremental additional investments can move the user closest to the intended goal, or at least provide a justifiable incremental value-add.”

An earlier article—“Building a Plant Asset Information Database” —discussed the plan of Interstate Power & Light’s Burlington Generating Station, Burlington, IA, to have high data integrity from the onset of its CMMS implementation. MT


Information supplied by Andy Carroll and Brian Moore. At the time of writing, Carroll was manager of Black & Veatch Corp.’s Plant Asset Management group, Overland Park, KS; (913) 706-5912 . Moore is a project manager at NRX Global Corp., Toronto, ON; (877) 603-4679

0704bvfig1

More than a parts list, the Visual BOM links equipment, parts, photographs, drawings, and manuals.

0704bvfig2

The project converted 52,151 images (or a 25-ft stack of paper) and 3576 drawings, digitized 3766 parts lists,
and matched 95,194 BOM line items to discrete equipment.

back to article Continue Reading →

403

6:15 pm
July 1, 2004
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Improved Storage Leads to Improved MRO

Maintenance, repair, and operations (MRO) is central to just about every type of manufacturing facility—with responsibilities that usually encompass both facilities maintenance, and machine repair and maintenance. An organized, smooth-running MRO department can keep a company operating efficiently, while an MRO department that is disorganized, inefficient, and ineffective can have negative ramifications that touch just about every aspect of a business—from overall productivity to employee safety to the bottom line.

Disorganization means employees cannot find the items they need when they need them. It is also a direct link to inaccurate inventories, unscheduled downtime, unexpected stockouts, overcrowded or inefficient use of space, and malfunctioning or nonfunctioning machinery.

If disorganization is the disease from which an MRO department is suffering, an improved storage system is a likely cure.

Storage system options
In general, a storeroom manager can consider three types of storage systems: conventional, automated, and high density.

Conventional storage. Conventional storage, with principal components that include shelving, racks, bins, or some variation of these elements, is most appropriate for large bulky items and items that are slower moving. Large quantities of products that do not require daily access or are stored and distributed in bulk are well suited for conventional storage. Pallet racks are used for items that are delivered on pallets or are very heavy and need to be moved by a forklift truck.

Automated storage and retrieval systems. This category includes horizontal and vertical carousel and lift systems, and control software. These systems store a lot of items in a relatively small footprint, particularly the vertical systems. Vertical systems also offer exceptional security access and so are well suited for the storage of valuable and limited access items. But vertical systems are expensive up front and can have a high maintenance price tag. Because they have moving parts and require a precisely balanced weight flow, they have potential to break down. Also, they can slow down stocking and retrieval, as they also only allow access to one operator at a time.

0704lista1High-density storage. This is the ideal solution for storing medium- to small-sized items. This category includes modular drawer storage cabinets, mobile cabinets, and other systems that feature subdividable drawers as their centerpiece. High-density storage can cure an MRO department’s disorganization because it offers benefits that conventional storage cannot—from complete use of cubic space to load capacity. High-density storage is also more affordable than automated systems. In short, it is the most efficient and cost-effective option.

Storage configuration options
Both high-density and conventional storage can be stacked or used in mezzanines to take advantage of a room’s full height while making maximum use of floor space. However, this can be a relatively expensive alternative to building an additional floor. Both can also be mounted onto a mobile aisle system, which comprises rolling rows of storage product with only one aisle accessible at any time. These space-saving systems eliminate wasted aisle space but are not the best solutions for fast-moving inventory.

Mobile modular drawer storage cabinets deliver all the flexibility and organized storage of high-density cabinets, while adding the benefit of convenience. With these mobile units, tools and parts can be rolled out directly to the job where they can be readily accessible to maintenance and repair personnel. These mobile workstations-on-wheels can be customized with the particular tool sets used by each craft. Repairs are performed more quickly and downtime is greatly reduced.

All of these systems, from conventional shelving to the most advanced high-density system, are most effective when combined with an integrated software system. Today’s software does an exceptional job of managing inventory levels and determining key performance indicators, helping to prevent future breakdowns and aid in predicting future needs.

Get it right from the start
It is important to set up a storage system correctly at the outset. Even the most sophisticated software and inventory systems are based on the principle of knowing where an item can be found and returned. Space planning is an essential first step, whether coordinated by your own staff or with the assistance of storage consultants or the manufacturers. Taking advantage of free design planning surveys by the manufacturer or its representatives can be a real cost-saver.

0704lista2The importance of the drawer
As mentioned earlier, the best high-density storage solutions are modular, allowing the selection of components that suit exact needs. These can include cabinets of varied heights and widths that offer many drawer height combinations. The modularity of these systems not only allows for custom-fitted storage, their interchangeable parts provide flexibility for future change and growth.

Modular high-density storage systems come in a wide range of sizes and shapes. There are also large wall units that combine drawers, shelves, and even rollout trays for storage of and easy access to heavyweight items. These units provide for storage of large, medium, and small items together; they can be stored according to need and craft vs stored by size. Such systems allow items in daily use (product broken down from bulk quantities to smaller, manageable quantities) to be mixed with bulk and slow-moving product for convenient access to both.

Another option is drawer storage units, which can be added to conventional shelving, providing a cost-effective way to improve existing storage without entirely replacing it.

The most important feature of high-density storage is the drawer. The best high-density drawers make the most use of full cubic capacity while providing easy, direct access to all tools, parts, and other stored items. These drawers should be able to handle a lot of weight. At full load, they should be 100 percent full extension, allowing every inch of space to be used and easily accessed. Look for drawers that have full-height sidewalls and backs, so that height as well as width and depth are available for storage.

Giving each part a home is essential for enabling MRO departments to function efficiently. Drawers that are easily subdividable into compartments allow such separation of individual parts. Preferable drawer dividers allow easy identification of compartment contents, including barcode labeling.

Most MRO stockrooms are broken down into multiple crafts. Technicians who specialize in different crafts need storage that can be organized according to their typical tasks. Compartmentalized storage is important when dealing with such a great variety of items and is essential to fast access and efficient service.

Organization is key
The primary mission of MRO personnel is to maintain and repair equipment in order to keep that equipment and the company operational. MRO fills an essential role, and the organization of tools and parts is essential to the department’s success. To minimize downtime and maximize productivity, consider the high-density storage options that promote the highest degree of organization. MT


John Alfieri is vice president of sales and marketing at Lista International Corporation, 106 Lowland St., Holliston, MA 01746; (508) 429-1350

Benefits of an Advanced Storage System

The benefits of implementing an advanced hardware and software storage system can include:
• Greatly reduced downtime (with predictive and preventive maintenance)
• A more efficient and productive workforce
• Improved operator safety (with machines and equipment functioning properly)
• Fewer product defects
• Lower inventory costs (greater visibility eliminates repetitive and blanket work orders; increased organization allows for the stocking of min/max quantities with reorder points)
• Faster and easier inventory process
• Faster parts picking and improved ergonomic access to more items with less operator movement and strain
• Improved use of valuable floor space
• A more aesthetically pleasing environment and more professional image

High-Density vs Conventional Shelving

To clearly understand the advantages of high-density storage, compare it to conventional shelving:
• High-density drawer storage uses all available cubic space and frees up floor space.
• Full-extension drawers, an important component of a high-density storage system, provide complete easy access. Upper levels and the rear of conventional shelves are hard to see and reach and often are not used. Items on shelves are often stacked, difficult to retrieve, and easy to lose.
• Inventory control is easy in compartmentalized storage because there is clear visibility. Shelving provides no efficient parts location system. Continue Reading →

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5:39 pm
July 1, 2004
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Do Not be Misled by OEE

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Robert M. Williamson, Strategic Work Systems, Inc.

Overall equipment effectiveness (OEE) has been used as one of the more important maintenance metrics since total productive maintenance (TPM) came to the U.S. in the late 1980s. OEE is the primary measure used in TPM to identify and quantify the major equipment-related losses and a metric for rating equipment effectiveness.

OEE has become widely used in many plants with or without the elements of TPM to quantify equipment effectiveness losses. This usage has also caused some confusion, and has led to many misuses of the OEE percentage calculation.

The early Toyota Production System focused on eliminating waste to reduce cost. OEE was initially developed to identify the major losses in equipment performance and reliability. TPM then became a company-wide approach to eliminating them. Here is a list of the original major losses:

Availability losses: Planned shutdown—no production scheduled, planned maintenance; downtime—breakdowns and failures, changeover (product, size), tooling or part changes, startup or adjustment

Performance efficiency losses: Minor stops (jams, circuit breaker trips, etc.) and reduced speed, cycle time, or capacity

Quality losses: Defects/rework, scrap, and yield (changeover, startup losses)

OEE, as a metric, is a calculated rating of equipment effectiveness represented by Availability x Performance Efficiency x Quality Rate, each expressed in percent.

Let the confusion begin
This is where all the confusion begins. OEE percentages became a metric to compare current equipment performance to world-class performance, typically pegged at 85 percent.

Once used as a benchmarking score for world-class, OEE then came to be used for comparing one piece of equipment to another, regardless of function or operating environment. OEE has been extended to specify overall plant effectiveness (OPE) by using an aggregate score for all equipment in the plant.

These metrics have become widely used to compare levels of maintenance effectiveness and equipment performance to world-class levels, and even a club to punish those whose OEE slips.

All of these uses are inaccurate, unfair comparisons, and a gross misuse of the original purposes of OEE.

OEE data: OEE was originally designed and developed to characterize and communicate the major equipment-related losses.

By capturing equipment performance and reliability data and classifying it as a specific availability, efficiency, or quality loss, Pareto charts could be developed to communicate the major losses for focused improvement. This OEE data then could measure and communicate the effectiveness of the focused improvement efforts and the countermeasures put in place to eliminate the major loss, or problem.

OEE percentage rating: The OEE percentage calculation served no purpose other than a very high-level indicator of performance improvement or degradation. Today, entirely too much emphasis is placed on trending and analyzing the calculated OEE rating.

OEE as a calculated rating is not entirely accurate. It assumes the basic factors of availability, efficiency, and quality losses are equally important. It is a rare situation when a 1 percent downtime loss has the same business or financial impact as a 1 percent efficiency loss or a 1 percent quality loss.

OEE is not a maintenance measure
OEE is not a measure of maintenance effectiveness—it is a measure of the factors that determine equipment effectiveness. Maintenance alone can address very few of the major losses captured for OEE. This is why OEE is used in total productive maintenance where the entire organization, including operations and engineering, focuses on eliminating the major losses.

OEE data very quickly leads to root cause identification and elimination. OEE data answers the question—did we eliminate the root cause of poor equipment performance? OEE data is the means to an end: improving overall equipment effectiveness.

However, calculating OEE ratings removes our efforts further from eliminating the major losses to comparing OEE scores.

Be careful—OEE is a measure of equipment effectiveness, not maintenance effectiveness. Don’t be misled by OEE. MT
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5:36 pm
July 1, 2004
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Parallel Alignment

bob_baldwin

Robert C. Baldwin, CMRP, Editor

The 2004 Directory of Enterprise Asset Management (EAM) and Computerized Maintenance Management System (CMMS) software lists major offerings. I recently had an opportunity to visit the headquarters of two of the companies listed and the people I talked to there echoed some of the things I have been hearing from other suppliers of maintenance information systems.

While stopping way short of saying they are in a commodity business, they agree that most of the primary maintenance management functions are available in all the packages on the market. They all manage work orders, track inventory, facilitate work planning, track costs, etc. They all deliver value to their users.

However, studies have shown that a surprising number of CMMS implementations fail—more than 50 percent by some estimates. If they all support core maintenance competencies and have the ability to deliver value, why do so many fail? Perhaps it is because those users are buying maintenance solutions (a favored term used by most software developers) rather than figuring out what they want to do and then buying a software tool to automate the process.

The companies I visited point out that their most successful customers have a well thought out maintenance and reliability process.

What is included in a well thought out processes? There are a number of recipes served up by consultants, but those are models. It takes a lot of hard work to build the real thing.

The three organizations sharing their experience at the Maintenance & Reliability Technology Summit have put in the hard work necessary to develop maintenance and reliability processes that work.

Each was unique to their company but they have a number of points in common. They have a vision, mission, goals, and measurements. They have a leadership team. They recognize the close relationship between good maintenance and reliability and enterprise performance.

And most importantly in my view, all three companies are looking beyond fundamental maintenance efficiency to maintenance effectiveness which depends on sucessfully embedding the principles of root cause analysis and reliability centered maintenance in their work processes.

The EAM/CMMS suppliers I visited were similarly focused on reliability analysis.

When leading users and leading suppliers are aligned, they must be heading toward significant value. If your alignment is not parallel to theirs, and you are not investing in reliability, it may be time to revisit your objectives. You may be missing something. MT

rcb

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