Pump Essentials and Package Familiarisation Webinar

Name: Pump Essentials and Package Familiarisation Webinar
Uploaded: 2025-11-26T11:26:42.000Z
Duration: 4 h 24 min 6 s

Introduction to the Webinar on Pump Essentials

Overview of the Webinar Structure

Christina Dörfel introduces the webinar, which is divided into three parts focusing on pump and package features, centrifugal pumps, and pump instrumentation.

After a brief break, Nick Arendt will discuss centrifugal pumps, followed by Maximilian Kotman covering vibrations in pump instrumentation.

Participants will receive a recording link post-webinar; no certificates or handouts will be provided.

Housekeeping and Presenter Introductions

Key Information for Participants

Kolya Mitternacht welcomes attendees and outlines housekeeping rules including Q&A procedures at the end of the session.

Attendees are advised not to record the session as it will be offered regularly for rewatching opportunities.

Presenter Background

Kolya shares his background as a technical trainer with Sultz Academy since 2023, previously working with Liva pumps and Fast-Mer service.

He is currently pursuing certification as a pump technician specialist at the University of Graz.

Introduction to Sultz Academy

Mission and Services Offered

The goal of Sultz Academy is to enhance understanding of pump technology to improve reliability and performance.

They offer both generic courses and bespoke training tailored to specific equipment needs.

Areas of Expertise

Sultz operates in three main service areas: Turbo Services, Pump Manufacturing, and Pump Services including repairs and retrofits.

Training formats include classroom sessions, hands-on workshops, online webinars, and e-learning options.

Overview of Pump Components

Common Pumps in Portfolio

Kolya begins discussing various common pumps starting with OH2 pumps suitable for high temperatures/pressures due to their centerline mount design.

OH1 vs. OH2 Pumps

OH1 pumps are foot-mounted with limitations on operating temperatures; commonly used in industries like sugar production and wastewater management.

BB Type Pumps

BB1 type pumps feature split foot-mounting; they are single or double-stage often utilized in crude oil pipelines.

Solza BBS Pumps

The BB2 type Solza BBS is designed for high-pressure services; it has radial split centerline mounting.

Pump Types and Applications

Overview of Multi-Stage Pumps

The flow transitions from the first to the second stage, featuring a BB3 pump (Solzer MSD), commonly used in refineries, pipeline operations, and desalination.

The BB4 type pump (MC or MD size from Solzer) is noted for its radial split design; however, it requires complete disconnection from the system for servicing.

Servicing challenges arise as the entire pump must be removed for rotor repairs, limiting its use in refinery operations.

Common Applications of Pumps

The BB4 pump is frequently utilized as a boiler feed pump in combined cycle power plants and high-pressure applications. It includes components like bearings and mechanical seals.

Typical arrangements for multi-stage pumps include bearings and balance devices that depend on operational speed and power requirements. An intermediate takeoff (ITO) allows secondary applications at lower pressure without needing an additional pump.

Barrel Casing Pumps

BB5 pumps are characterized by their radial split design and are often employed as boiler feedwater pumps or for ethylene shipping.

In contrast to previous models, the barrel casing of BB5 pumps is welded rather than bolted, allowing maintenance on the insert while keeping the casing stationary.

Split Cartridge Design

Another variant of BB5 features a split cartridge design that simplifies maintenance through a twist lock arrangement instead of traditional bolting methods.

This back-to-back impeller arrangement indicates efficient pressure management within the pump's structure.

Vertical Pump Designs

Characteristics of Vertical Suspended Pumps

VS6 vertical suspended pumps have impellers located beneath bearings with inline pipework under double casing or suction can designs.

Components include product lubricated bearings and rigid couplings connecting motor to pump shaft. Mechanical seals are positioned just below the motor.

Applications in Shipping and Pipeline Boosting

These vertical pumps serve various functions such as LPG shipping, tank farm boosting, and crude oil pipeline boosting.

Bearing Types in Pump Systems

Anti-Friction Bearings

Various anti-friction bearing types include deep groove ball bearings, angular contact bearings, and cylindrical roller bearings which comply with API specifications regarding speed and energy density requirements.

Hydrodynamic Bearings

Hydrodynamic sleeve-type bearings can function both as standard bearings and thrust bearings under high loads.

Thrust Bearing Functionality

Entry friction thrust bearings handle most radial loads near mechanical seals in end-suction pumps while journal or line bearings support other areas closer to drive mechanisms.

Lubrication Considerations

Importance of Lubricant Selection

Proper lubricant selection is critical; options typically include oil or grease but may also involve using pumped liquids depending on bearing style. Running temperatures significantly influence lubrication effectiveness.

Understanding L10 Fatigue Life and Bearing Types

L10 Fatigue Life Explained

The L10 fatigue life refers to the number of hours or revolutions that 90% of identical components are expected to remain operational under specific conditions, with only 10% likely to fail due to fatigue.

For instance, a bearing with an L10 life of 30,000 hours indicates that out of 100 identical bearings, 90 will last the full duration while 10 may fail earlier.

Types of Bearings

Anti-Friction Thrust Bearing

The anti-friction thrust bearing is designed for high forces and customer preferences; it requires proper lubrication systems for optimal performance.

These bearings often include a cage between rolling elements (balls) to prevent contact and reduce friction.

Functionality and Efficiency

Anti-friction bearings convert sliding friction into rolling friction, which is significantly lower, making them ideal for pumps and motors where efficiency is crucial.

Lubrication Methods

Oil Bath Lubrication

Oil bath lubrication involves partially submerging the bearing in oil, allowing rolling elements to pick up oil as they rotate. This method supports higher rotational speeds compared to grease lubrication.

Maintaining the correct oil level is critical; it should reach the centerline of the lowest rolling element. Low levels can lead to overheating or damage.

Ring Oil Lubrication

In ring oil lubrication, a rotating ring picks up oil and delivers it directly to the bearing. This design minimizes churning losses compared to immersion methods.

Constant monitoring of oil levels is essential; incorrect levels can cause poor lubrication and overheating.

Sliding Contact Bearings

Design Considerations

Sliding contact bearings rely on sliding motion rather than rolling elements. They often use pumped liquid as lubricant and require careful material selection for durability.

Applications

Commonly used in vertical pumps with multiple bearings along the shaft, these designs must consider fluid properties like particle presence.

Key Takeaways on Bearing Types

Sliding contact bearings are effective for clean fluids but necessitate careful material choices for longevity.

Hydrodynamic Bearings Overview

Operation Principle

Hydrodynamic radial or journal bearings utilize a thin film of lubricant under pressure to separate the shaft from the bearing surface.

Material Composition

These bearings typically feature surfaces coated with materials like antimony or copper alloys that enhance heat transport capabilities and resistance against seizure.

Bearings and Their Applications

Types of Bearings

Various types of bearings are discussed, including sloth bearings and angular contact rolling element bearings, commonly used in large pumps and high-speed operations.

Different shapes of bearings are introduced: cylindrical bearing shell, offset journals, multilobes, lemon bore, and tilting pad thrust bearings.

Bearing Failures

A "wiped" bearing failure is described as smearing or melting of the surface due to insufficient clearance, improper oil supply, or overload forces.

Visual details show polished areas on the bearing indicating wear from contact with the shaft.

Construction and Maintenance of Bearings

Components of a Bearing System

Key components include the 360 mounting (bearing housing), journal bearing, shaft with thrust disc and pads, and oil drain.

Oil Supply Systems

Proper oil pressure maintenance is crucial for keeping the oil film intact; flow regulation is necessary for lubrication and cooling.

Equipment for monitoring includes flow meters for control, heaters for cold environments, coolers for hot conditions, and temperature indicators throughout the system.

Oil Cleanliness Management

Filtration Systems

Duplex filter systems allow switching between filters while one is cleaned to maintain oil cleanliness.

Side glasses help check oil levels and detect dirt; sampling points enable laboratory checks on oil quality.

Loop Oil System Overview

System Design

A typical loop oil system includes pumps with pressure relief set at 15 bar; continuous pressure maintained at 9.3 bar.

Viscosity Considerations

The relationship between VG46 oil at different temperatures highlights viscosity importance in operational efficiency.

Couplings in Pump Systems

Types of Couplings

Rigid couplings such as split/bolted ones or solid sleeve couplings transmit torque through keyways to pumps effectively.

Disk Coupling Features

Disk couplings accommodate small misalignments due to thermal growth rather than poor alignment during setup.

Mechanical Seals Explained

Purpose of Mechanical Seals

Mechanical seals prevent leakage from pump fluids into the environment; they are installed near the impeller within a steel chamber.

Seal Components Breakdown

Key components include product side (left), atmospheric side (right), seal sleeve, seal ring combined with mating ring, flexible elements like springs or bellows for movement allowance.

Mechanical Seal Arrangements and Systems

Overview of Mechanical Seals

The discussion begins with the introduction of static secondary seals, such as O-rings, which are essential for sealing in mechanical systems.

A single seal arrangement is highlighted, showcasing its role in preventing leakage from pumps handling clean and non-hazardous fluids.

Locking Mechanisms and Seal Preparation

The importance of locking mechanisms during transport, installation, and storage is emphasized; these prevent movement until the seal is ready for operation.

Various connections for seal supplies are introduced: flush (F), buffer inlet (LBI), buffer outlet (LBO), quench (Q), and drain (D). Their usage depends on specific pump operations.

Seal Supply Systems

Plan 11 is described as a simple arrangement involving plugged flush and drain connections suitable for single seal applications with clean fluids.

An adaptation to Plan 12 includes a filter to enhance functionality while maintaining suitability for clean fluids.

Multi-stage Pump Configurations

For multi-stage pumps, more complex piping arrangements are necessary. Plan 23 utilizes a closed-loop system with a pumping ring to maintain fluid flow.

This plan is particularly important during maintenance to ensure correct installation direction to avoid reverse flow through the mechanical seal.

Advanced Seal Plans

Plan 53B incorporates a heat exchanger and an accumulator with a bladder that separates gas from barrier fluid; it’s used in dual seal arrangements.

Barrier pressure must be maintained at least 1.4 bar above maximum pressure inside the seal chamber, requiring regular bladder refills approximately every 28 days.

Quench Plans and Alternatives

C-plan 62 serves as a quench plan often used alongside flush or barrier plans; it helps remove debris from mechanical seals effectively.

A plan 61 acts as a backup quench plan for future use alongside plan 62 arrangements.

Conclusion of Presentation

The presentation concludes with an overview of assembling a common pump package known as a pump skid, detailing components like the water injection pump and motor integration.

Emphasis on safety features such as coupling guards highlights the importance of secure assembly in operational settings.

Training Opportunities at Sulzer Academy

Tailored Training Programs

Sulzer Academy offers customized training courses designed to enhance product knowledge among clients' maintenance teams, improving system reliability and efficiency.

Training on Pump Technology and Efficiency

Overview of Training Content

The training aims to enhance both theoretical and practical knowledge in areas such as pump technology, maintenance, hydraulics, and applied theory. This is particularly beneficial for personnel in engineering support, management, procurement, and operations.

Pumping systems are significant energy consumers, accounting for over 20% of the world's electrical energy demand; in some cases, they can represent up to 90% of a plant's total energy usage.

Cost Reduction Strategies

Trainees learn methods to reduce operational costs by minimizing downtime through early detection and resolution of vibration issues.

Emphasis is placed on planned maintenance and condition monitoring rather than relying on reactive failure-repair cycles.

Understanding Pump Operations

Key concepts include understanding pump curves for optimal efficiency and the implications of using variable speed drives at higher speeds due to increased power costs.

The use of CAD files allows trainers to incorporate interactive 3D models into presentations, enhancing product training by providing a visual understanding of hardware.

Hands-On Experience in Training

Depending on the location, various decommissioned pumps and full-size replicas may be available for hands-on experience during training sessions.

Courses are designed to foster cross-functional teamwork among participants from different job roles, ensuring a comprehensive understanding of equipment.

Transitioning to Hydraulic Principles

Nick takes over the presentation focusing on hydraulic principles including cavitation and best operational practices after Kylia’s introduction.

Understanding Pump Mechanics

Basic Functionality of Pumps

Pumps function primarily by moving liquid from one point (A) to another (B), requiring that the suction vessel is positioned higher than the pump itself for effective operation.

Operational Requirements

Essential requirements for centrifugal pumps include mechanical soundness throughout their lifespan while minimizing power consumption and leakage of pumped fluids.

Managing Heat and Noise Generation

Pumps generate heat within both the fluid being pumped and their internal components; managing this heat generation is crucial for longevity.

Addressing Vibrations & Corrosive Effects

Noise and vibrations are inherent characteristics during pump operation; these must be managed effectively alongside erosive or corrosive effects caused by the pumped liquid.

Pump Design Characteristics

Types of Hydraulic Designs

Two primary hydraulic designs exist: volute design with an involute-shaped casing that follows a snail shell pattern, allowing fluid passage along its shape;

Diffuser design features impellers discharging into stationary diffusers which slow down liquid flow before channeling it back into subsequent stages.

Hydraulic Pump Design and Functionality

Overview of Diffuser and Volute Designs

Diffuser designs are commonly used in multi-stage pumps, channeling flow back into subsequent stages to build pressure through impellers and diffusers. Both volute and diffuser designs have been manufactured for over 150 years.

Impeller Characteristics

The impeller is the core component of a pump, with both advantages and disadvantages in design. There is no definitive superior design between volute and diffuser arrangements.

Key Attributes of Impellers

Important attributes include eye diameter (preferably large for optimal flow), hub diameter (mechanical rigidity preferred by mechanical engineers), and outer diameter (critical for generating pressure).

Pressure Generation Methods

Pressure can be generated through three methods: increasing the outer diameter, increasing rotational speed (up to 6000 RPM), or adding more impellers. Each method has trade-offs.

Affinity Laws Impact on Performance

According to affinity laws, increasing the impeller tip diameter results in increased pressure but also higher power consumption—10% increase in diameter leads to 21% more pressure but 33% more power usage.

Flow Dynamics within Pumps

The width of the impeller affects flow rates; wider impellers allow for greater flow. Impellers generate flow by pushing liquid outward due to centrifugal force.

Balancing Hydraulic Forces

Thrust Dynamics in Impellers

Centrifugal force pushes liquid outward while centripetal force acts inward. High pressure at the tip of the impeller primarily directs into diffusers, but some pressure moves towards the suction side.

Balancing Techniques for Single Stage Pumps

To balance thrust in single-stage pumps, wear rings can be adjusted for larger diameters or balanced chambers can be created at the back of the impeller.

Additional Balancing Methods

Other methods include using back veins on the rear hub to redirect liquid away from it or employing double suction impellers that naturally balance axial thrust due to dual inlet design.

Multi-stage Pump Thrust Balancing Solutions

Advanced Thrust Balancing Techniques

Multi-stage pumps utilize additional balancing techniques such as balanced disks, balanced drums, or back-to-back impellers to manage thrust effectively across multiple stages.

Balanced Disk and Drum Mechanisms in Pumps

Understanding the Balanced Disk

The term "balanced disk" is preferred over "balanced piston" to accurately describe the geometry rather than just the function of the component.

High pressure pushes through a gap, moving the rotor towards the discharge side, counteracting thrust from impellers directed towards suction.

This mechanism balances axial thrust, eliminating the need for tilting pad thrust bearings and associated lubrication systems, simplifying pump design.

During startup and shutdown, wear may occur between components; a magnetic device might be necessary to prevent contact during these phases.

Exploring the Balanced Drum

The balanced drum features an annular clearance between a rotating drum and a stationary liner, allowing for high-pressure liquid flow that helps balance thrust.

It effectively manages 95% of axial thrust but requires a thrust bearing for the remaining 5%, necessitating lubrication systems again.

Unlike balanced disks, balanced drums do not rub against each other during startup/shutdown, making them more suitable for multiple cycles.

Potential Issues with Clearance

Over time, if clearance increases beyond acceptable limits (0.2mm to 0.5mm), it can lead to equalized pressure on both sides of the drum, resulting in no net positive thrust and potential overheating of thrust bearings.

The imbalance causes all impeller thrust to drag against the shaft towards suction, stressing bearings significantly and leading to premature failure.

Observations on Thrust Pads

Inboard pads experience higher loads due to their position relative to impeller forces; they often show signs of wear compared to outboard pads which see less stress during operation.

Visual inspections reveal that inboard pads may appear obliterated while outboard pads show minimal damage; this can mislead assessments about which set bears more load over time.

Investigating Failures

Identifying root causes of failures can be complex without thorough investigation; issues could stem from increased clearance or loss of oil supply affecting lubrication efficiency.

Gradual temperature increases suggest wear due to clearance issues; sudden changes indicate possible lubrication blockages leading to rapid failures in pump systems.

Multi-Stage Pumps: Understanding Back-to-Back Impellers

Mechanisms of Balancing Thrust in Multi-Stage Pumps

The third mechanism for balancing thrust in multi-stage pumps involves back-to-back impellers, as seen in a BB3 pump configuration with four impellers on each side.

The design features mirror-image impellers (four clockwise and four counterclockwise), allowing multiple impellers to build pressure effectively through the pump.

Pressure Management and Mechanical Seals

A pressure breakdown occurs between high-pressure (impeller 8) and lower-pressure (impeller 4) zones, utilizing a clearance and restriction bush that acts as a bearing to support the shaft.

Despite API 610 guidelines suggesting tilting pad bearings for certain power-speed ratios, exceptions are often requested when thrust is balanced by back-to-back configurations.

Importance of Restriction Bushes

The restriction bush allows flow through a small gap (0.2mm clearance), similar to a balance drum, reducing mechanical seal pressure from potentially dangerous levels down to manageable values.

Regular maintenance every five years is crucial due to wear on the restriction bush; increased clearance can lead to higher pressures at the mechanical seal, risking failure.

Common Misconceptions About Mechanical Seals

Operators often blame seals for failures without considering that issues may stem from upstream components like the restriction bush affecting seal performance.

Design Considerations in Pump Efficiency

In examining another back-to-back design, it’s noted that discharge branches indicate flow direction changes within the pump casing.

A CP multi-stage pump example illustrates complex flow paths through multiple impellers before reaching discharge, emphasizing efficiency trade-offs inherent in such designs.

Advantages and Disadvantages of Back-to-Back Designs

Utilizing ball bearings instead of tilting pad bearings simplifies maintenance since no lubrication system is required, enhancing reliability and ease of use.

However, this design incurs some efficiency costs due to directional changes in fluid flow compared to inline configurations which would be more efficient but require extensive lubrication systems.

Understanding Pump Performance Curves

Introduction to Performance Curves

The speaker introduces the topic of performance curves, noting that many people find them intimidating. The aim is to simplify the concept for better understanding.

Basic Principles of Pump Operation

Pumps operate on the principle that flow out equals flow in, unlike compressors. The pressure output from a pump is determined by the input pressure plus delta P (total dynamic head).

Generating Performance Points

When operating a pump with a valve at its normal point, flow and pressure are measured to establish points on the performance curve.

Closing the valve reduces flow while increasing upstream head, allowing multiple data points to be plotted on the curve.

Consequences of Valve Closure

If a valve is closed completely, flow drops to zero while head reaches maximum; this situation leads to excessive heat generation and potential damage.

Operating under these conditions can cause mechanical seals to fail and ultimately destroy the pump if not corrected promptly.

Testing and Measuring Efficiency

During performance tests, key metrics such as head (pressure), absorbed power, and efficiency (head times flow divided by power input) are recorded.

Understanding NPSHR (Net Positive Suction Head Required)

After extensive testing, suction tank levels are lowered until performance begins to degrade due to insufficient suction pressure.

This threshold indicates where vaporization occurs, affecting pump operation; measurements taken at this point help plot the NPSHR curve.

Implications of Cavitation Over Time

As pumps age (e.g., after five years), their performance curves shift leftward: reduced efficiency and increased power draw occur alongside higher NPSHR requirements.

Importance of Maintenance

Regular maintenance every five years is crucial to prevent inefficiencies and cavitation issues that could lead to operational failures.

Interaction with System Resistance Curve

The intersection of the pump performance curve with the system resistance curve determines operational efficiency; factors like pipeline friction influence this relationship.

Understanding Pump Performance and System Dynamics

Key Concepts of Pump Operation

The discharge tank's height creates a static head, while dynamic head accounts for pressure losses due to friction and bends in the piping system. The intersection of the pump performance curve with the system resistance curve indicates operational flow and pressure.

Closing the control valve on the discharge side increases pressure but decreases flow, shifting the pump's performance curve downwards as it ages. This results in lower operational efficiency over time.

Customers often increase pump speed using variable frequency drives to compensate for wear, which can lead to a 33% power increase for every 10% speed boost. It's advised to consider upgrading or overhauling instead.

Parallel Pump Operations

When operating pumps in parallel, their performance curves combine; however, starting a second pump does not double flow due to real-world inefficiencies. Instead, it shifts onto a shallower performance curve.

Adding more pumps leads to diminishing returns in flow increase. For instance, starting a third or fourth pump yields less noticeable improvements compared to adding the second one.

Managing Multiple Pumps

In scenarios where multiple pumps are running (e.g., A and C active while B is standby), switching off one may temporarily increase overall flow if another is started simultaneously without issues arising from this transition.

Individual contributions of each pump change when additional pumps are activated; thus, when returning to two pumps after running three, individual contributions revert back to original values.

Performance Variability Among Pumps

The operation of an additional pump affects individual performances significantly; understanding these dynamics is crucial during transitions between different operational states.

Running dissimilar pumps (e.g., large vs small) in parallel can create challenges; smaller pumps may struggle against higher pressures from larger ones due to non-return valves preventing proper operation.

If a small pump attempts operation alongside a larger one under high downstream pressure conditions, it will be unable to function effectively until its output matches that of the larger unit at equilibrium.

Understanding Pump Performance and Operating Regions

Impact of Mismatched Pumps

When a small pump contributes only 20% of the flow while a large pump provides 80%, it leads to high vibrations, temperature, turbulence, and cavitation in the small pump. This highlights the importance of matching pumps to avoid operational issues.

Influence of Liquid Levels on Pump Performance

The performance of a pump is affected by the liquid level in the suction tank. As the static head increases due to higher water levels, it influences system resistance and flow rates.

Changes in liquid levels cause shifts in flow characteristics; as water levels rise or fall, they push the entire performance curve up or down, affecting flow rates without altering pump speed or valve positions.

Static Head Variations

Similar effects occur with vertical pumps during tidal changes; variations in static head lead to corresponding changes in flow rates at high and low tides.

The pressure and level of liquid entering the pump directly alter its operating characteristics, emphasizing the need for maintaining optimal conditions for efficiency.

Preferred Operating Region

To ensure efficient operation, pumps should ideally function within a preferred operating region between 70% and 120% of their best efficiency point (BEP).

Hydraulic engineers define allowable operating regions based on specific parameters provided in datasheets to guide safe operational practices.

Consequences of Poor Operation Conditions

Closing valves can shift operational points leftward on performance curves, leading to decreased efficiency. If closed too much, this results in cavitation and backflow vortexes—conditions that necessitate immediate attention.

Continuous operation outside allowable regions can lead to mechanical failures due to temperature buildup and other stresses on components. Instrumentation is crucial for monitoring these conditions effectively.

Importance of Monitoring Instruments

Different industries have varying standards for instrumentation; oil and gas sectors typically employ more extensive monitoring compared to water industries due to cost considerations associated with equipment failure risks.

Proper instrumentation should alert operators about critical parameters like power consumption, bearing temperatures, and vibrations before reaching failure points.

Flow Dynamics at Inlet Conditions

Visualizing inlet pipe conditions reveals how stable flows maintain optimal performance at 100% BEP.

As discharge valves close further into allowable zones, turbulence increases significantly near the inlet—a condition that should be avoided for prolonged periods.

Understanding Pump Operation and Vibration Analysis

Impact of Flow Conditions on Pump Performance

Closing the suction valve can lead to 40% preferred operator efficiency, resulting in turbulent liquid flow. This turbulence can cause vaporization and backflow, potentially damaging the pump due to unstable laminar flow.

Similar effects occur when lowering the water level in the inlet tank to zero, leading to cavitation and other detrimental conditions that can destroy the pump.

Presenter Introduction

Nick Arons introduces himself as an engineer with 35 years of experience, including 15 years at Weir pumps and eight years as a technical trainer. He emphasizes his extensive knowledge of pump operations.

Transition to Vibration Analysis

The presentation transitions to Maximilian Kottmann, a vibration specialist who will discuss instrumentation related to pump performance and vibration analysis.

Importance of Instrumentation in Pump Monitoring

Kottmann highlights that proper instrumentation is crucial for assessing pump conditions. Key measurements include bearing temperature, bearing vibration, shaft vibration, etc., which help identify potential issues before they escalate.

Early detection allows operators to shut down pumps or make necessary adjustments economically rather than facing costly repairs after failure.

Vibration Measurement Standards

There are established standards (API 610 and ESO 810-816) that define acceptable vibration limits for pumps. Alarms indicate when limits are exceeded while trips automatically shut down pumps to prevent damage.

Operating above acceptable limits increases wear on components like rotors and reduces overall performance, shortening mean time between failures (MTBF).

Methods of Measuring Vibration

Common tools for monitoring vibrations include proximity probes and casing-mounted accelerometers. Accelerometers measure amplitude and frequency on structures like bearing housings or pump casings.

Proximity probes detect movement in rotating elements such as shafts or rotors by being fitted through holes in casings aimed at polished areas of shafts.

Challenges with Probe Installation

Improper installation of probes can lead to damage or misreadings during operation, causing false alarms for high vibrations even when there are none present.

To protect against damage during assembly or production, coatings may be applied over sensitive areas; however, underlying damage must still be assessed carefully beneath these coatings.

Temperature Monitoring in Pumps

Various parts within a pump package have their temperatures monitored—such as motor bearings and loop oil systems—to maintain optimal operating conditions using thermal wells installed in pressurized environments.

Understanding Temperature Sensors and Vibration Analysis in Pumps

Characteristics of Temperature Sensors

Thermocouples (TC) are preferred for detecting very high temperatures, capable of measuring over 2,000 degrees Celsius, while Resistance Temperature Detectors (RTDs) are limited to around 500-600 degrees Celsius.

RTDs can be directly inserted into sleeve bearings to accurately measure the temperature of the bearing material.

Instrumentation in Pump Monitoring

Typical instrumentation for pumps includes monitoring shaft vibrations in two directions (NDE and DE), bearing temperatures, balance return temperature, and speed measurements at the coupling.

A Process and Instrumentation Diagram (PNID) visually represents these measurements including temperature probes, vibration probes, and displacement probes.

Analyzing Vibration Signals

Understanding vibration signals involves analyzing a vibration spectrum with amplitude on the y-axis and frequency on the x-axis; frequencies are often expressed as multiples of running speed.

Specific frequencies can indicate issues in rolling element bearings: ball pass frequency for outer/inner raceway defects and cage rotational frequency for damage detection.

Impeller Blade Interaction Frequencies

The blade passing frequency is crucial for pumps; it indicates how many times an impeller passes a fixed point per revolution. For example, at 2980 RPM with six blades, this results in a vane passing frequency of approximately 298 Hz.

In diffuser-type pumps, interactions between impeller blades and diffuser edges occur at higher frequencies than vane passing frequencies.

Gear Damage Detection through Vibration Analysis

Damaged gear teeth produce distinct vibration signatures based on their location; high-speed pinion damage shows up at 1x pump running speed while motor-driven gear damage appears at half that speed.

Multiple damaged teeth may complicate diagnosis due to higher frequency peaks appearing in the spectrum but low amplitude levels may indicate no immediate concern.

Critical Machine Speed Considerations

Most pumps should operate below their natural or resonant frequency to avoid critical speeds that lead to excessive vibrations causing potential damage.

Understanding Machine Operating Speeds and Vibration Issues

Importance of Operating Speeds

Knowing the operating speeds, critical speed, and natural frequency of machinery is essential to prevent resonance issues that can cause high vibrations and operational problems.

High-speed machinery should operate above critical speed during startup and shutdown; using steep ramps with frequency converters can help pass through natural frequencies quickly.

Identifying Coupling Misalignment

A dominant peak around 2x the running frequency in radial direction indicates coupling misalignment; immediate shutdown for realignment is recommended.

Addressing Unbalance in Machinery

A peak at 1x the running order suggests unbalance; shutting down machinery for rotor rebalancing is crucial to avoid bearing damage.

The impact of unbalance increases with higher speeds, necessitating prompt corrective action.

Recognizing Cavitation Symptoms

Poor flow patterns due to low speed can lead to cavitation; a broadband noise level in vibration spectra indicates this issue.

Analyzing Pump Behavior

A plot from a positive displacement pump shows dominant peaks caused by pistons moving within the housing at a running speed of 1480 rpm.

Understanding specific machine documentation is vital for diagnosing anomalies like peaks at 9x running speed related to piston movement.

Vibration Standards and Alarm Levels

Amplitude levels are significant: 4mm/s is acceptable, while above 10 or 11mm/s should trigger machinery trips. Referencing ISO10816 provides guidelines on alarm values based on machine size and criticality.

Q&A Session Insights

Lubrication Choices for Bearings

Oil lubrication generally supports longer bearing life under high loads and speeds due to better film stability and temperature control.

Grease lubrication works well under normal conditions but may be preferred for lower speeds where easy sealing and low maintenance are desired.

API Plan Zero Two Drain Options

For API plan zero two systems, having a drain is optional; it serves as a convenience rather than a functional requirement during maintenance.

Forces on Thrust Bearings Explained

Thrust bearings experience radio forces from imbalance and hydraulic forces from impellers. Axial forces arise from pressure differences across impeller surfaces, with balance drums absorbing most axial loads initially. Over time, thrust load absorption shifts more onto the thrust bearing as wear occurs.

Understanding Pump Operating Ranges

Importance of Regular Pump Overhaul

Pumps should be overhauled every five years to prevent overload on thrust bearings, ensuring longevity and efficiency.

Clarifying API 610 Terminology

A distinction is made between allowable operating range and preferred operating range as per API 610 standards.

Preferred Operating Range Explained

The preferred operating range is defined as 70% to 120% of the best efficiency point, where pumps can operate indefinitely without concern for efficiency metrics.

Allowable Operating Region Insights

The allowable operating region is determined by hydraulic engineers and includes areas outside the preferred range; it permits short-term operation during specific transitions (e.g., changing pump configurations).

Risks of Operating Outside Recommended Ranges

Operating beyond the recommended limits (above 130% or below 30%-40% of best efficiency) risks catastrophic failures such as motor overheating or pump destruction. Short durations in these zones are only acceptable under strict conditions.

Conclusion and Further Engagement

The session concludes with an invitation for further questions via email, emphasizing ongoing support from Schulze Academy for participants seeking additional information.