the purpose and process of bently nevada machinery

The Purpose and Process of Bently Nevada Machinery Protection and Condition MonitoringMark Snyder | Senior Field Application Engineer

GE Oil & Gas

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GEA32852 Bently Nevada Purpose and Process

© 2016 General Electric Company. All Rights Reserved. This material may not be copied or distributed in whole or in part, without prior permission of the copyright owner.

Table of ContentsPurpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Appendix A – Benefits of a Plant-wide Condition Monitoring System . . . . . . . . . . . . . . . . . . . . . . 9

Appendix B – Machine Criticality Ranking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10High Criticality machinery (HC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Critical machinery (C) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Medium Criticality machinery (MC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Low Criticality machinery (LC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Non-Critical machinery (NC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Appendix C – Typical Machine Criticality Nominations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13FCC Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Catalytic Reforming Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Delayed Coker Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Hydro-cracking Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Alkylation Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Distillation Unit/Pipestill . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Desalter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Vacuum Distillation Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14Cryogenic Recovery Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14Hydro-treating Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14Sulphur Unit/Tail Gas Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14Flare Gas Recover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14Tank Farms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Appendix D – Protection and Condition Monitoring System Descriptions . . . . . . . . . . . . . . . . . 15Critical Rotating Machinery Measurements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Critical Reciprocating Machinery Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Machine Data Acquisition System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Monitoring and Alarming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Remote Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Highly Critical and Critical Assets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Medium and Low Criticality Assets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Entry level protection system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Wired Scanning Condition Monitoring System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Wireless Scanning Condition Monitoring System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Offline Portable Data Collector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

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Bently Nevada Purpose and Process GEA32852


Appendix E – Machinery Measurement Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Rotating Machinery Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Keyphasor® Probe for Speed and Phase Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Thrust Position – fluid film thrust bearing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Radial Vibration – journal bearings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Casing Vibration – Gearbox, Fluid Coupling and Integrally Geared Compressor . . . . . . . . . . . . . . . . . . . . . . . . . 20

Reciprocating Machinery Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Reciprocating Compressor MEW Keyphasor® Probe for Speed & Phase Measurement . . . . . . . . . . . . . . . . . 21Reciprocating Compressor – Compressor Frame Vibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Reciprocating Compressor Crosshead Vibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Reciprocating Compressor Piston Rod Position . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Reciprocating Compressor Valve Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Reciprocating Compressor Cylinder Internal Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

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Note: the following discussion is in the context of an oil refinery, but the same concepts apply to power generation and other industries.

PurposeThere is relentless pressure to focus on short-term objectives and reactive activities, despite the well-documented benefits of proactive operations and maintenance practices. One study found that a typical 225,000 bbl/day refinery can reduce maintenance expenses by 15% and save $8.5M per year by moving from time-based to condition-based maintenance (see Figure 1). The study also found that an additional $3.0M and $924k in annual savings can be realized through related improvements in availability and thermodynamic efficiency, respectively.

Another report (Figure 2) found that “Best-in-class” performers using condition-based maintenance experience 6% lower maintenance costs (as a percent of revenue) and 5% higher asset productivity (as a percent of capacity) relative to their “Laggard” peers who use reactive (failure-based) maintenance.

Condition Monitoring Value Proposition – Re�ning

Operating Expense Cost/Barrel – $3.24$4.10 – US Gulf Coast • $2.70 – SE Asia

Value Proposition – 225,000 BBD Re�nery (Top 25 USA)

Potential Improvement of Reducing Maintenance expenses 15%, shifting from time-based to condition-based maintenance1

$8.4M per year

Maintenance Cost @ $0.76/BOL

Energy Use @ $1.25/BOL

Throughput margin improvement by 1% incremental availability increase from 90% average @ $3.40 net margin

$3.0M per year

1EPRI suggests 30-35% from non-PG benchmark study w/o reliability mgmt.Source: Honeywell, OGJ

Potential 1% improvement in e�ciency through improved thermal performance

$924K per year

MaintenanceCost

24%

Other

18%

Energy Cost

38%

Non-Maint.Purchases

18%

Figure 1: Condition Monitoring Value Proposition

Figure 2: Condition-Based Maintenance Benefits

CBM BenefitsPerformers Maintenance

ApproachMaintenance Cost (% of Revenue)

Maintenance Strategy

Asset Productivity (% of Capacity)

Best-In-Class Proactive Condition Based

17.2% Standardized Processes and KPIs, Proactive, TPM, PdM, RCM,RCA, PFA, 79+% Planning

84.2%

Average PM Time or Rate Based

20.8% No Standardization, Routine PM most Common Approach, Some PdM, Some PFA, 56% Planning

81.9%

Laggards Reactive Failure Based

23.5% Reactive Break/Fix Approach, Minimal PM, Little PdM, Little PFA, Minimal Planning

79.2%

Per Billion of Revenue Variance (Best to Laggard) 6.3% or $63,000,000.00Per Million Barrels Produced Variance (Best to Laggard) 5% or 50,000 Bpd

Data Source: Aberdeen Group Report

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These numbers show that the odds favor a return-on-investment from a proactive condition-based maintenance strategy that far exceeds the cost of the condition monitoring tools required to implement it. The reasons for this become obvious when viewed through the lens of how machines fail and how failures are detected.

Referring to “How Equipment Fails” (Figure 3), the vast majority (89%) of machinery assets experience a random failure pattern. In the context of a preventive (scheduled) maintenance strategy, where a consistent time to failure is assumed, machinery protection systems serve primarily to protect the machine from failures that occur unexpectedly between scheduled maintenance intervals.

A machinery protection system, such as the 3500 & TDI shown in Figure 5, is defined as a system that reliably shuts down a machine or returns it to a safe or nondestructive mode of operation without human intervention. A machinery protection system is the

last line of defense against excessive machinery stress, unplanned events, and abnormal operating conditions that could threaten or damage human life, the environment, or other plant assets.

On the P-F curve (Figure 4), the machinery protection system is represented by the red and yellow dots on the lower right portion of the curve, around the point of functional failure. This is the point at which the levels of vibration, temperature, or other measurements have exceeded a threshold set high enough to accommodate all normal operating conditions of the machine. Although a machinery protection system and associated transducers can serve as the front end hardware for a condition monitoring system, their primary purpose is an aid to operators in detecting conditions where they must intervene to place the machine and associated process in a safe condition, up to and including shutdown. The obvious question is: why let things get to this point?

How Equipment Fails

A11%

Wearout

Non-Wearout

89%

2%

4%

5%

7%

14%

68%

B

C

D

E

F

A Look at Failure Patterns…

“Traditional View”Random failure, eventual wear-out zone

“Slow Aging”Steady increase in failure rate

“Best New”Sharp increase in failure then random failure

“Worst New”High infant mortality then random failure

Original Source: 19XX XXX StudyQuoted Source: XXX-XXX XXXX RCM Document

A time-based or rate directed strategy will be e ective for assets with these failure patterns – but they represent a small percentage of the asset population.

Based on these statistics, the majority of equipment do not wear out in a time interval that can be forecast with reasonable accuracy. Therefore, a condition-based strategy is the most e ective for the majority of the asset population.

Figure 3: How Equipment Fails

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As mentioned, most machines fail randomly. Except for the unusual sudden “lightning strike” type of failure, these random failures are preceded by detectable signs of deteriorating condition weeks or even months ahead of time, as illustrated by the purple dots on the curve in Figure 4. These indications are often below the threshold of the machinery protection system alarm level, are only a component or derivation of the

measurement made by the protection system, or use a technology not suitable for automatic protection. Consequently, additional signal processing and plotting capabilities, beyond those of the protection system, are required for the early detection of developing problems.

A condition monitoring system, represented by the combination of hardware and System 1 software

Time – Varies based upon failure mode

Con

dit

ion

The P-F interval is the interval between the occurrence of a potential failure and the decay into a functional failure.

Time can be measured in seconds, minutes, days, months, or years.

P1-Px indicate detectability intervals by various techniques or technologies

P = Potential Failure

Is an identi�able condition which indicates that a functional failure is either about to occur or is in the process of occurring

F = Functional Failure

The point at which the asset fails to deliver its intended purpose

The P-F Interval

Centrifugal Pump – Mechanical Failure Mode Example

P P1

VibrationP-F interval1–9 months

P2

Wear Debris in oilP-F interval1–6 months

P3

Process Performance Data(highly dependent on tuning of system/instruments

~1 week–6 months

P4

IR ThermograpyP-F interval3–12 weeks

P5

Quantitative PMP-F interval5–8 weeks

P6

Audible NoiseP-F Interval

1–5 days

P7

Heat by TouchP-F interval

1–5 days

F

Relays

Figure 4: The P-F Curve

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in Figure 5, is defined as a system that detects subtle change in machine conditions and identifies root-cause machinery failure modes for maintenance work planning. It facilitates machinery management and optimization by utilizing a range of mechanical condition, thermodynamic performance, oil analysis, and other technologies. The system incorporates technologies and methodologies that optimize asset availability while reducing life cycle

support costs. In essence, a condition monitoring system is a proactive tool for the majority of machines that should be managed using a condition-based maintenance strategy where random failures are common or could severely impact safety, production, or profitability. Appendix A describes the typical benefits of a condition monitoring system.

System 1 Asset Management Platform

Online – Continuousmonitoring and protection

O�ine• Portable

• Lube analysis

• Thermography

Critical Assets• Steam Turbine Generators

• Gas Turbine Generators

• Bioler Feed Pumps

• Critical Fans

Essential Assets• ID/FD/PA Fans

• Pumps

• Cooling Fans

• Motors

• Etc.

Online – Periodic(scanning/wireless) monitoring

Switch/Hub

3701 ADAPT

3500 & TDI

AnomAlert

EssentialInsight.mesh

SCOUTPortable

DataCollector

3500 Encore Trendmaster® Pro

Figure 5: Typical Plant Asset Management Platform

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ProcessAlthough there are different ways to approach the task of improving the maintenance strategies used at a production facility, they usually contain some or all of the following elements in one form or another:

• Assess systems and assets in a plant process to determine level of risk and opportunity for advancement with regard to safety, regulatory and environmental compliance, production, operational and maintenance costs, and product quality.

• Analyze and rank potential failure modes based on likelihood and risk.

• Review maintenance and cost history of systems and assets to determine areas where condition monitoring solutions can provide immediate benefit.

• Assess current level of technology systems, methodologies being applied, and organizational structure.

• Define what information flow is required to drive improvements.

The first item usually involves an asset criticality ranking criteria that varies from customer to customer. An example of the criteria that Bently Nevada uses to rank the criticality of equipment in a plant is contained in Appendix B. This ranking and the other elements listed above determine the appropriate maintenance strategy and tools that are applied to each asset. Appendix C is a list of machines grouped by units in a hypothetical refinery and their suggested criticality rankings for reference. Appendix D is a description of the protection and/or condition monitoring systems corresponding to each category of asset criticality. Appendix E is a description of common measurements made on rotating and reciprocating machinery.

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Appendix A – Benefits of a Plant-wide Condition Monitoring System• A long-term reduction in the labor costs and an

increase in the quality of data: On-line systems automate the tedious and time-intensive tasks of setting up and configuring temporary portable analyzers, manually collecting data via a “walk-around” data collection program, and converting and presenting data into a usable format. The consistency and quality of the data is improved because the measurements are fixed and reliable. On-line systems do not eliminate the need for a competent rotating machinery engineer to interpret the information, but they greatly reduce the process time to actionable information.

• Reduction in machinery maintenance cost (general): Accurate and real-time data enables engineering and maintenance personnel to better predict and schedule the most appropriate maintenance. Machinery problems can be detected and corrected before they cause damage. A distressed machine can be more intelligently operated and managed until it can be removed from service for repairs.

• Reduction in machinery maintenance costs (critical machinery): Data captured at higher sampling rates during alarm and transient (i.e., abnormal) events is invaluable for identifying machine degradation and determining the root cause of machinery problems. Without an on-line system, machinery engineers may be forced to make momentous decisions regarding machinery availability (i.e., restart) despite a lack of sufficient information.

• Significantly reduce the high costs of expert diagnostics: As on-site expertise may not be available at all times, an on-line machinery management system’s ability to provide remote access to critical diagnostic information is often essential in providing timely information as well as minimizing travel costs.

• Increased earnings because of continuous process improvement: On-line systems provide immediate feedback for operations, thereby enabling them to quickly and accurately assess the impacts of process changes upon machinery and vice versa. Improved product quality is a natural consequence of improved machine availability.

• Exchange data to leverage the power of correlation and optimization: Today’s state-of-the-art systems use Windows™ operating systems that enable network communications across the plant or enterprise, and myriad abilities to share data with other operations and maintenance systems.

• Reduced Insurance costs: By demonstrating fully functioning on-line machinery management systems, it is often possible to obtain better insurance coverage at lower premiums. An interesting technical paper entitled, “Rotating Equipment Loss Prevention—An Insurer’s Viewpoint,” by Edward E. Clark, of The Hartford Steam Boiler Inspection and Insurance Company provides an insurer’s insight into the area of machinery management. A copy can be provided upon request.

• Automatically retain valuable expert knowledge and information: If rotating equipment knowledge is not stored and transferred from older to newer generations of engineers and operators, important corporate learning does not take place. Costly mistakes may be repeated. A Machinery Management system embeds and retains this knowledge for the duration of the machine’s life.

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Appendix B – Machine Criticality RankingCriticality of each plant equipment asset is assessed and ranked using failure impact on several business level factors, including: Safety, Regulatory and Environmental Compliance, Production, Operations and Maintenance Costs (O&M) and Product Quality.

The criticality ranking of equipment assets in the system will influence the Maintenance Strategy which in turn will be used to define the corresponding asset management level of effort and resulting technologies that will be applied. See the example chart below.

The results of Criticality Ranking are used to categorize machinery types by criticality and to define the resultant Maintenance strategy.

Criticality is very specific to asset application, environment, end user business needs, system design, end user operational strategy, and the resulting consequence or impact of failure of the machine being ranked.

Criticality Ranking is performed by assessing consequence of failure of each piece of equipment in 5 key areas of impact including:

1. Safety

2. Regulatory and Environmental Compliance

3. Production

4. Operations and Maintenance Costs (O&M)

5. Product Quality.

Questions are developed specific to the End Users business philosophies in the 5 key areas of impact that allow for granularity in the ranking across the Plant Wide equipment base.

Note that Criticality Ranking DOES NOT define the level or rate of data acquisition and analysis applied to equipment assets. Criticality Ranking categorizes equipment assets into specific groupings so that the right maintenance strategy tools can be applied and the proper maintenance strategy developed, see right side of the chart above.

Maintenance strategies aimed at early fault detection and mitigation utilize Condition Monitoring technologies as the means for early fault detection. From the Maintenance strategy the specific asset failure modes and failure cycles (called P-F) will be determined and in return will define the proper technologies, data acquisition frequency (on-line, scanning, periodic) and overall all asset management strategy to be used to mitigate those specific failure modes.

Plant Equipment Criticality

Monitoring Strategy Maintenance Strategy Tools

Protection, ProcessPortable, Performance,

Scanning RCM

ProcessPortable, Performance,

ScanningFMEA

ProcessPortable, Scanning

Process

PM Templates

Run to Failure

5%Highly

Critical

10 – 15%Critical

30 – 40%Mid Level Criticality

45 – 55%Low Level Criticality

5 – 10%Non Critical

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Below are some definitions and general examples of technology applications that may be found in each category.

High Criticality machinery (HC)Where the consequence to the business has been ranked in the highest band, machinery (for a specific failure mode and cycle) often time requires protection and real-time on-line condition and performance monitoring. The protection and management system should include an independent integration to the plant DCS using Modbus over TCP/IP. For specific failure mode and cycles associated with these machines the maintenance risk has been determined to be high and the machinery requires a more stringent monitoring and protection regime. Where called for (failure mode), thermodynamic performance is required for managing typical failure modes on the machine type.

Typically, highly critical machines for a specific failure mode and failure cycle are:

• Protected with an automatic shutdown system such as 3500 or 3701, Multilin or other applicable protection device

• Managed with System 1, part of an on-line asset management program

• Managed with predictive analytics systems such as SmartSignal

• Managed with motor current anomaly detection systems like AnomAlert

• Optimized with thermodynamic performance using Bently Performance

• Monitored with a Rotor/Stator Insulation monitor similar to HSCT

• Managed with System 1 using an on-line scanning system like Trendmaster or Essential Insight.MESH

• Managed with System 1 using the SCOUT100/140 portable condition monitoring data collector

• Managed with Lubrication Condition and Analysis data integrated into System1

Critical machinery (C)Machines categorized as Critical require localized protection to reduce consequences of failure. The localized protection system shall integrate to the plant DCS using Modbus over TCP/IP.

Where determined by the maintenance strategy (i.e. failure mode) development process, Critical machines may also be monitored using an on-line or on-line scanning condition monitoring system.

Typically, critical machines are:

• Protected with an automatic shutdown system such as 3500, 3701 or 1900/65A or other protection device




• Optimized with thermodynamic performance using Bently Performance

• Monitored with a Rotor/Stator Insulation monitor similar to HSCT




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Medium Criticality machinery (MC)Machines categorized as Medium Criticality do not typically require protection and shall be managed using on-line scanning or portable machinery condition monitoring systems. The localized Protection (if utilized) and condition monitoring system shall integrate to the plant DCS using Modbus over TCP/IP.

Typically, medium critical machines are:

• Protected, if required, with an automatic shutdown system such as 3701, 1900/65A or other protection device




• Managed with thermodynamic performance using Bently Performance




Low Criticality machinery (LC)For low criticality machines, portable data collectors and related off-line PdM techniques. Online scanning or online wireless periodic condition monitoring technology may be called for under appropriate conditions where human risk is involved in data collection or where a measurement location is inaccessible in operation. The condition monitoring system shall integrate to the plant DCS using Modbus over TCP/IP.

Typically, medium critical machines are:



• Managed with System 1 using an on-line scanning system like Essential Insight.MESH


Non-Critical machinery (NC)Equipment ranked in the non-critical category will, in most cases, only be managed using OEM recommended PM tasks or a run-to-failure strategy.


A comprehensive asset criticality ranking will be required to properly categorize each asset in a refinery. This is an exercise that will require one or more personnel to perform the study based on maintenance history, production cost, Failure Mode Effect Analysis (FMEA) etc.

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Appendix C – Typical Machine Criticality Nominations

FCC Unit

• FCC Feed Pump – HC

• Wet Gas Compressors – HC

• Main Air Blower – HC

• Main Air Blower Steam Turbine (ST)/Motor – HC

• Power Recovery ST/Expander – HC

• Overhead Condenser – MC

• General Purpose Pumps – MC

• Fin Fans – MC

• Other non-critical assets – NC

Catalytic Reforming Unit

• Hydrogen Recycle Compressor – HC

• Net Gas Compressor – HC

• Fin Fan Heat Exchangers – MC

• Motor Operated Valves – LC



Delayed Coker Unit

• Coker Wet Gas Compressor – HC

• Motor Driven Centrifugal Pumps – HC

• Vent Gas Compressor – HC

• Overhead Condensers – MC

• Coke Drum – LC


Hydro-cracking Unit

• Hydrogen Make-up Compressors – HC

• Recycle Compressors – HC

• Charge Pumps – MC

• Heat Exchangers – MC

• Valves – LC


Alkylation Unit

• Refrigeration Compressor – HC

• Condensers – MC

• Mixers – MC


Distillation Unit/Pipestill

• Feed Pumps – HC

• Overhead Condenser – MC

• Fin Fan Heat Exchanger – MC

• Feed Exchangers – MC



Desalter

• Water Pumps – HC

• Transformers – MC

• Mix Valves – LC


14



Vacuum Distillation Unit

• Vacuum Ejector/Pump – HC

• Bottoms Pump – MC


Cryogenic Recovery Unit

• Turbo Expander – HC

• Gas Compressor – HC


Hydro-treating Unit

• Hydrogen Make-up Compressor – HC

• Recip Recycle Compressor – HC

• Charge Pumps – HC

• Heat Exchangers – MC

• Valves – LC


Sulphur Unit/Tail Gas Unit

• Boiler Feed Water Pumps – HC

• Reactor Air Blower – HC

• Sulfur Pumps – MC


Flare Gas Recover

• Recip Compressor – MC

• Sealed Water Circulation Pump – MC

• Water Sealing Pump – MC

• Valves – LC


Tank Farms


• Tank Mixers – MC


15



Appendix D – Protection and Condition Monitoring System Descriptions

Critical Rotating Machinery Measurements• XY Vibration Measurements at each bearing

• Once per turn reference signal

• Dual Rotor Position

• Acceleration HF Applications

• Phase reference for ease of balancing and malfunction location

• Bearing Metal Temperature

• Performance Measurements (Efficiency, Power Output, etc.) calculated from existing process measurements integrated into new system for a proactive management system

• Process Measurements (flow, pressure, load, temperature, etc.) from existing systems integrated into new system

Critical Reciprocating Machinery Measurements• Motor Stator Temperature

• Motor Bearing Temperature

• Motor Bearing Vibration

• Main Bearing Temperature

• Crankshaft position Reference with MultiEvent Wheel

• Frame Vibration

• Crank Pin and Crosshead Pin Bushing Temperature

• Crosshead Vibration

• Case Temperature

• Vent Line Temperature

• Internal Cylinder Pressure

• Valve Temperature

• Suction and Discharge Temperatures

Machine Data Acquisition System• Multivariable Trend Plots

• Plot overlay capability for diagnosis

• Full and Half Spectrum Plots

• Full and Half Waterfall Plots

• Bode and Polar Plots

• Full and Half Spectrum Cascade Plots

• Orbit Plots

• Shaft Centerline Plots (monitor changes in alignment)

• Acceptance Region Plots (shaft crack diagnosis)

Monitoring and Alarming• Each sensor is monitored and has two alarm setpoints

• Monitor provides a relay output for shutdown.

• Shutdown can be configured to require two sensors to alarm before shutdown, providing redundancy not provided by current system.

• Monitor connects with the plant computer system for trending and advance diagnosis.

Remote Monitoring• A data acquisition computer will provide trending

and diagnostic displays. The system will also include hardware and software to supply start up and shut down data.

• The data can be displayed on any machine on the plant network.

• The data can be displayed over a modem if required.

Figure 1 breaks assets down into three general classifications: Critical, Essential, and Balance of Plant (BOP). The following pages describe the monitoring method typically used for each asset class. Refer to Figure 2 for an illustration of the different methods.

16



Classi�cation of Assets

Highly Critical and Critical AssetsDirect production impact, high capital cost,high risk, long lead time parts

1&2 3 & 4 5

Number of Plant Assets

Ris

k an

d/o

r Op

por

tuni

ty

Medium and Low CriticalityFrequent production impact,high maintenance costs, medium-high risk

Non CriticalInfrequent production impact,low individual maintenance costs,medium-low risk

Figure 1: Criticality Graph

System 1 Asset Management Platform

Online – Continuousmonitoring and protection

O�ine• Portable

• Lube analysis

• Thermography

Critical Assets• Steam Turbine Generators

• Gas Turbine Generators

• Bioler Feed Pumps

• Critical Fans

Essential Assets• ID/FD/PA Fans

• Pumps

• Cooling Fans

• Motors

• Etc.

Online – Periodic(scanning/wireless) monitoring

Switch/Hub

3701 ADAPT

3500 & TDI

AnomAlert

EssentialInsight.mesh

SCOUTPortable

DataCollector

3500 Encore Trendmaster® Pro

Figure 2: Examples of Various Monitoring Methods

17



Highly Critical and Critical Assets

Online Continuous Monitoring & Protection Systems are typically most appropriate for these classes of assets. The following specific requirements should be met by the monitoring and protection system:

• Dual Redundant Power Supplies in accordance with API 670 4th edition. The specific voltages and power sources (AC or DC) for each power module are site specific and shall be approved by the HollyFrontier Refining Engineering Manager prior to delivery. For highest reliability each power supply should be connected to separate power feeds through UPS devices.

• Minimum of one Alarm Relay and one Trip Relay for each critical protection or monitoring function (additional to any SIL-3 protection functionality). Relays may be grouped onto a multi-channel card, so one Relay card may support the entire monitor rack. Unless otherwise specified by the site Engineering Manager, the following relay functions (and more) shall be supported by a common relay card:

– Mechanical Protection: shaft vibration, bearing temperature (2 Relays)

– Thrust Protection: when SIL-3 protection is not required (2 Relays)

• The protection system shall collect, store and communicate dynamic vibration data and alarm and system events to the data acquisition system.

• Fully programmable Modbus communications card for interface to plant DCS via RS-232/422, RS-485, and/or Ethernet TCP/IP.

• Display panel to indicate all monitor rack status, alarm and event history, trend plots and bar charts. Single unit to display all relevant data for monitor racks within each location (i.e., Instrument room).

For Critical classification machinery, an acceptable level of protection can be achieved by either the Bently Nevada 3500 or Bently Nevada 1900/65A systems. Under the selection criteria below, either of these technologies will meet the machinery management strategy for Critical machines.

• Bently Nevada 3500 system shall be selected when:

– Machine train has fluid film (journal) bearings.

– Number of sensors on a protected machine(s) is higher than eight (8).

– When redundancy on power supply or communication is required.

– Zero speed or reverse rotation monitoring is required.

– Fast data acquisition for condition monitoring is required.

– When more than one Keyphasor is required.

– When SIL compatible requirements are identified.

• Bently Nevada 1900/65A shall be selected when:

– Number of measurement channels is eight or less and that a Keyphasor is not required.

– Local protection is needed.

– Advanced algorithms to monitor rolling element bearings is required

Medium and Low Criticality Assets

Depending on plant need assets in this class may need all of the same protection systems as the critical assets listed above, but many can utilize lower cost solutions such as an entry level protection system or a wired or wireless mulitplexing scanning system.

Entry level protection system

• Bently Nevada 1900/65A shall be selected when:

– Number of measurement channels is eight or less and that a Keyphasor is not required.

– Local protection is needed.

– Advanced algorithms to monitor rolling element bearings are required.

18



Wired Scanning Condition Monitoring System

• Online periodic data acquisition is typically applied to Critical and Medium Criticality machines.

• Consists of field hardware and a data acquisition server computer to collect, store, and display steady state static and dynamic vibration data, and other machine-related measurements (pressures, temperatures, and analog inputs).

• Simple system architecture consists of field “sensor bus” cabling with multiple independently accessed, ”daisy-chained” sensors. For faster data collection, a scanning module with multiple sensor direct inputs can be used.

• Fully programmable Modbus over Ethernet communications for interface to plant DCS.

Wireless Scanning Condition Monitoring System

• Bently Nevada Essential Insight.Mesh (EI.Mesh) wireless mesh architecture can be used on nominated Medium and Low Criticality machine assets including motors, pumps, fans and compressors. This shall be applied where human hazards or accessibility problems restrict the application of traditional walk-around condition monitoring methods.

• The EI.Mesh data acquisition system shall collect, store and communicate steady state dynamic vibration data and temperature.

• Mesh architecture consisting of a gateway, data collection motes, sensors and repeater motes.

Offline Portable Data Collector

• The Bently Nevada SCOUT 100 Portable Data Collector (PDC) is to be used for off-line periodic collection of Low Criticality and Non-Critical rotating machinery and fixed asset data using hand held transducers or via manual entry. It shall be a lightweight 2-channel (plus phase reference) microcomputer based instrument with interchangeable sensors for vibration and other process parameters in harsh industrial environments. The device shall acquire both time domain and frequency domain spectra. Minimum requirements will be as follow:

– High resolution display to present data in several modes, including dual screen display of time domain and frequency domain spectra.

– It shall be a 2-Channel input device, including input for speed or phase reference measurements.

– It shall utilize a long life battery-pack that may be replaced in the field without a loss of data.

– The system software shall be an integral module to the machinery condition monitoring platform and provide historical measurement trends, waveform, orbit, magnitude/phase vector plots, single and multiple FFT spectra, and comparisons to alarms and stored data.

– It shall be approved for use in Class 1, Div. 2 hazardous areas. Vendor must also demonstrate availability of compatible Intrinsically Safe data collector.

19



Appendix E – Machinery Measurement Descriptions

The following sections described best practice and industry standard measurements in detail for critical rotating and reciprocating machines. It does not address the less critical or auxiliary machines in the plant.

Rotating Machinery Measurements

Keyphasor® Probe for Speed and Phase MeasurementA Keyphasor® transducer is necessary for accurate phase information and must, as a minimum, be mounted on the shaft of the driver machine. The target notch or protrusion should be suitable to generate the correct signal at all machine states.

• One non-contact proximity transducer shall be installed for once-per-rev phase reference measurements. For machines with internally mounted transducers, a spare transducer shall be installed, with extension lead delivered to the transducer interface housing, external to the machine.

• For Gearboxes, Fluid Couplings and Integrally Geared Compressors, one Keyphasor® sensor must be installed on each shaft for once-per-rev phase reference measurements (unless already installed on the driver or driven machine on the same shaft).

Thrust Position – fluid film thrust bearingA thrust bearing failure can quickly lead to catastrophic machine failure. Dual thrust transducers must be installed at each thrust bearing in order to detect thrust bearing degradation and/or failure. For SIL 3 applications, three probes shall be installed, connected to triple modular redundant monitors.

The preferred mounting arrangement for the thrust probes is directly through the thrust bearing, but the machine design does not always permit this. Thrust probe installation may also be engineered to observe the end of the shaft (within 300mm of the thrust collar), or another collar on the shaft within a similar proximity to the thrust bearing.

• Two non-contact proximity displacement transducers in a dual-voting configuration to be installed in accordance with API 670 4th edition, at each hydrodynamic thrust bearing. For SIL 3 applications, three probes must be installed .

• For Gearboxes and Integrally Geared Compressors, a single axial proximity displacement transducer to be installed on each pinion shaft without a thrust bearing. (Most API compliant gearboxes are manufactured with pre-machined probe mounting locations at the pinion shafts) Specialty sensor designs such as “Button probes” may be employed for this purpose when the geometry of the machine prohibits conventional sensors.

OneRevolution

0°

-V

OneRevolution

0°

-V

Thrust Collar

12" Max

12" Max

20



Radial Vibration – journal bearingsThe thin fluid film that supports the shaft, in a fluid film bearing, permits shaft movement relative to the bearing. Two orthogonally mounted proximity transducers are required to observe this shaft motion.

Protection parameters related directly to machinery internal clearances can be enabled using simply the overall amplitude and DC position measurement. A range of chronic problems and acute fault conditions (i.e.: misalignment, unbalance, shaft rub) can be diagnosed effectively using the dynamic signal output from the proximity probes.

• Two non-contact proximity displacement transducers in XY configuration shall be installed at each journal bearing in accordance with API 670 4th edition

Casing Vibration – Gearbox, Fluid Coupling and Integrally Geared CompressorAcceleration measurement on the gearbox and fluid coupling housing can provide the proactive maintenance planning system with a valuable source of information on progressive damage to gear elements. Specific mechanical fault symptoms related to gear wear or sudden damage can be detected through on-line vibration analysis.

General purpose accelerometers installed in accordance with API 670 4th edition are suitable for this application.

• For critical Gearbox and Fluid Coupling monitoring and protection, two accelerometer transducers shall be installed, in accordance with API 613. The transducers shall be located at the input and output bearing, on the coupling side, and be mounted radially on, or adjacent to, the bearing boss with axis aligned as close as practical to the principal load direction. (OEM should advise recommended mounting orientation)

• For Integrally Geared Compressors, two accelerometer transducers shall be installed on the bull gear housing. The transducers shall be located on each side of the casing, and be mounted radially on, or adjacent to, the bearing boss with axis aligned as close as practical to the principal load direction. (OEM should advise recommended mounting orientation)

CouplingThrust brg

Seismic Transduceron brg Boss

ImpellorPinion

Seismic Transducer

Bull Gear

“X” Proximity Probe“Y” Proximity Probe

Bearing

Rotor

21



Reciprocating Machinery Measurements

Reciprocating Compressor MEW Keyphasor® Probe for Speed & Phase MeasurementAngular velocity of reciprocating machines is not constant and, for High Criticality reciprocating compressors, a more accurate crank angle measure is needed to accurately calculate individual cylinder thermodynamic performance losses. These machines represent significant business risk, so best-in-class proactive machinery monitoring is mandatory. A specialized multi-event wheel (MEW) must be installed for High criticality reciprocating compressors.

• For all high criticality reciprocating compressors, a Keyphasor® shall be installed to observe a suitable multi-event wheel mounted on the end of the shaft. If shaft-end mounting is not possible, a split-collar design may be used, subject to approval by the Engineering Manager

Reciprocating Compressor – Compressor Frame VibrationThe dynamic forces acting on reciprocating compressors are transmitted through the bearing to the frame, resulting in crankcase vibration at one or two times machine running speed. Machinery malfunctions can significantly alter the dynamic pressure forces across the machine, resulting in unacceptable

vibration behavior, or subtle changes which may warn of a developing problem.

API 618 requires frame vibration to be monitored as a machine protection parameter.

• Low-frequency Piezo-velocity transducers shall be mounted on the crankshaft frame in the horizontal direction at each main bearing. Mounting the transducers level with the bearing split line is preferred, as it places them in the direct path of the forces acting on the machine.

• Sensor shall be supplied complete with mounting plate or thread adapter and bearing housing shall be suitably drilled and tapped to accept the sensor or housing thread. If the Vendor supplied probe housing is not utilized, the mounting surface must be spot faced to avoid pre-stress of the sensor.

Reciprocating Compressor Crosshead VibrationImpact-related events characteristically cause free vibrations and are typically due to liquid ingestion into the cylinder or mechanical problems such as looseness in the crosshead and piston assembly. Installing accelerometers over each crosshead provides the single best method to detect machinery problems due to impact-type events.

One Accelerometer transducer shall be mounted on the crosshead guide directly above the crosshead in the vertical plane at each cylinder.

Frame

CrossheadCrosshead Guide

CrCrCrCC ossheadCrosshead Guide

CrossheadCrosshead Guide

22



Reciprocating Compressor Piston Rod PositionTo monitor the progressive wear of the piston rider bands and schedule maintenance prior to incurring damage to the cylinder liner, two orthogonally mounted proximity transducers are required to monitor the radial location of the piston rod. When the piston moves too close to the cylinder wall in any direction, an alarm or danger signal will be generated.

• Two non-contact proximity displacement transducers in XY configuration shall be mounted directly on the high-pressure packing gland at each cylinder.

Reciprocating Compressor Valve TemperatureDuring normal process conditions, an increase in the gas temperature near a valve is a primary indication of a failing valve. Faulty valves can significantly reduce the efficiency of the compressor to the stage where a forced shutdown is required. Time-based maintenance of High Criticality Reciprocating Compressors is usually too conservative and reduces Overall Equipment Effectiveness unnecessarily. Further, routine replacement of good valves actually introduces a whole new set of infant mortality failures and can actually reduce the reliability of these machines.

In the early stages of valve failure, the temperature of the valve rises quickly. As the failure of the valve progresses, the temperature begins to return to normal. Therefore, on-line valve temperature measurement is required on all Critical Reciprocating Compressors to identify the specific location of the failure for better targeted planned maintenance.

• At each valve (inlet and discharge) an RTD shall be installed as close to the valve as possible. With the new O-ring type valve cover, installation of the probe into the gas passage is possible. This is accomplished by mounting a thermowell directly to the valve cover that enters the gas passage. The thermowell should extend into the gas passage as far as possible allowing placement close to the valve.

• There are other temperature measurements that can be monitored such as pressure packing temperature, pressure packing vent line temperature, gas discharge temperature, crank pin and crosshead pin bushing temperature etc. However, the cost to add these measurements may be hard to justify if they don’t already exist. If these are existing measurements, they can be easily connected to the machinery management system for monitoring and diagnostics purposes.

Reciprocating Compressor Cylinder Internal PressureFor High Criticality reciprocating Compressors, the most effective method for root cause analysis and proactive management of compressor health is achieved using on-line thermodynamic performance analysis. This provides valuable information on the condition of suction valves, discharge valves, piston rings, packing glands, and crosshead pin. This technique cannot be used on hyper compressors or reciprocating compressors with cylinder pressures greater than 10,000 psig.

Pressure ports are required on each chamber of the cylinder. Each cylinder shall have one dynamic pressure transducer mounted at the head end chamber and one at the crank end chamber. Typically all API compressor cylinders will be supplied with pressure ports (Per API 618, 5th Edition, Section 6.8.4.1.16). (The sensor must be suitable for continuous operation in a corrosive sour gas environment with a frequency response exceeding 5kHz). Cylinder pressure transducers are mounted to an isolation valve. Typically, this is a Kiene double block and bleed isolation valve that mounts on the cylinder pressure ports.

PackingCase

Flange

Head EndIsolationValve

Crank EndIsolationValve

Crank EndPressure

Transducer

Head EndPressure

Transducer

PistonRod

23



Imagination at work

For more information please contact:

GE Oil & Gas North America: 1-888-943-2272; 1-540-387-8726 Latin America (Brazil): +55-11-3958-0098 Europe (France): +33-2-72-249901 Asia/China (Singapore): +65-6622 1623 Africa/India/Middle East (U.A.E.): +971-2-699 7119

Email: [email protected] Customer Portal: ge-controlsconnect.com

1800 Nelson Road Longmont, CO, USA 80501

www.gemeasurement.com/machinery-control

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*Trademark of the General Electric Company.

GEA32852 (10/2016)

the purpose and process of bently nevada machinery

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