Calgary Pump Symposium 2013
Positive Displacement Pumps
Chad Wunderlich Viking Pump
Calgary Pump Symposium 2013
Calgary Pump Symposium 2013 Calgary Pump Symposium 2013
Chad Wunderlich Viking Pump Engineering Manager – Technical Customer Service 13 Years Experience
Calgary Pump Symposium 2013
Agenda
• Define the difference between positive displacement (PD) and kinetic pump technologies.
• Explore the strengths and weaknesses of each • List examples of where PD pump technology is
typically favored and why.
Calgary Pump Symposium 2013
Calgary Pump Symposium 2013
Agenda
• Look at various positive displacement principles.
• Explore how they operate, each one’s strengths and weaknesses, and list applications where each is commonly used.
Calgary Pump Symposium 2013
Calgary Pump Symposium 2013
PUMPS
POSITIVE DISPLACEMENT KINETIC
CENTRIFUGAL REGENERATIVE TURBINE ROTARY RECIPROCATING
Pump “Family Tree”
Calgary Pump Symposium 2013
Pump Sales
010203040506070
%
Centrifugal
Rotary PD
Diaphragm
Reciprocating
Turbine
Other
Centrifugal 67%, Other 33%
Calgary Pump Symposium 2013
Centrifugal Pump Principle
Calgary Pump Symposium 2013
Centrifugal Pump Principle A centrifugal pump
generates a low pressure area in the impeller to draw fluid in. (The same as a PD Pump)
The fluid velocity is increased as it travels outward along the Impeller.
Velocity is converted to pressure in the diffuser or volute. The pump is a pressure source.
Calgary Pump Symposium 2013
Centrifugal Pump Principle
Centrifugal pumps generate head (pressure) and flow results.
Calgary Pump Symposium 2013
Positive Displacement Pump Principle
Volume of liquid displaced by the ball
Calgary Pump Symposium 2013
Rotary PD Pump Principle A Positive Displacement (PD) pump displaces a known
quantity of liquid with each revolution of the pumping elements. This is done by trapping liquid between the pumping elements and a stationary casing
Calgary Pump Symposium 2013
Rotary PD Pump Principle A PD pump creates
flow. Pressure created is a result of system restrictions such as pipe shear, liquid shear, or work required (hydraulic systems)
PD pumps generate flow and pressure results.
Calgary Pump Symposium 2013
Centrifugal / PD Comparison PUMP
CHARACTERISTICS
PUMP PRINCIPLE
Kinetic (Centrifugal)
Rotary (Positive Displacement)
Viscosities Handled Typically water-thin
30-3,000 SSU (1-750 cSt)
Typically lubricating liquids 30-Millions SSU (1-1M cSt)
Pressure Low
Up to 500 PSI (34 BAR)
High Up to 3,000 PSI (200 BAR)
Speed High
1150-3450 RPM Medium
1750 RPM or less
Capacity High
To 100,000 GPM (20k M³/hr)
Medium To 3,000 GPM (700 M³/hr)
Efficiency Rapidly drops with increasing viscosity / pressure Relatively High
Performance (Flow) Smooth Smooth
Suction Characteristics Not Self Priming Very Good
Calgary Pump Symposium 2013
Centrifugal to PD Comparison
Calgary Pump Symposium 2013
Review – Low NPSH or Suction Lift Applications – High Viscosity Applications – High Pressure Applications – Low Flow, High Head Applications – Flow Rate Control Required (Metering) – Variable Service Conditions (Pressures,
Viscosities, etc.) – Energy Usage Concerns (Efficiency) – Shear Sensitive Liquids
When to Use PD Pumps
Calgary Pump Symposium 2013
Positive Displacement Pump Principles
• There are over 100 different PD principles and variations available. Each with their own unique advantages and disadvantages.
• Due to time I will be discussing only a few of the most common types. Each is commonly used in oil and gas applications.
Calgary Pump Symposium 2013
Calgary Pump Symposium 2013
PD Pumps to be Covered
• Rotary – Gear
• Internal Gear • External Gear
– Vane – Timed Lobe
• Reciprocating – Hydraulically Actuated Diaphragm – AOD (Air Operated Diaphragm)
Calgary Pump Symposium 2013
Calgary Pump Symposium 2013
Internal Gear Pumps
Calgary Pump Symposium 2013
Internal Gear Pump Operating Principle
Calgary Pump Symposium 2013
Internal Gear Pump Operating Principle
Calgary Pump Symposium 2013
Internal Gear Pump Design
Relief Valve
Relief Valve • Provides over-pressure
protection • All positive displacement
pumps need to have some form of over-pressure protection
Calgary Pump Symposium 2013
Internal Gear Pump Advantages
• ADVANTAGES • DISADVANTAGES
• Only one stuffing box • Ideal for high-viscosity liquids • Operates well in either direction • Can be made to operate with one
direction of flow with either rotation
• Low NPSH required • Single adjustable end clearance • Flexible design offers application
customization
• Usually requires moderate speeds • Medium pressure limitations • One bearing runs in the product
pumped • Overhung load on shaft bearing
Calgary Pump Symposium 2013
Internal Gear Pump Performance Range
FLOW RANGE 0.5 TO 1600 GPM
VISCOSITY RANGE
0.1 cPs - 1,000,000 cPs
MAXIMUM DIFFERENTIAL PRESSURE 400 PSI (2800 kPa)
TEMPERATURE RANGE -100°F to 800°F (-80°C to 425°C)
Calgary Pump Symposium 2013
Example Applications
Asphalt refining, transfer, blending, and delivery
Calgary Pump Symposium 2013
Example Applications
Pipeline sampling
Calgary Pump Symposium 2013
Example Applications
• Well Stimulation (hot oil trucks)
• Shale Fracturing (frac trucks)
• Gathering (wellhead to local storage)
• Transfer (local storage to terminal, barge or refinery)
Calgary Pump Symposium 2013
Example Applications
Lube oil blending, loading/unloading
Calgary Pump Symposium 2013
External Gear Pumps
Calgary Pump Symposium 2013
External Gear Pump Operating Principle
Calgary Pump Symposium 2013
External Gear Pump Operating Principle
Calgary Pump Symposium 2013
Gear Cuts
Spur Gears Helical Gears Herringbone Gears
• Lowest Cost • No thrust
• Moderate Cost • Lower noise • Lower NPSH • Thrust in opposite
directions
• Highest Cost • Lower noise • Lower NPSH • No thrust
Calgary Pump Symposium 2013
Double Pumps
Calgary Pump Symposium 2013
External Gear Pump Advantages
ADVANTAGES DISADVANTAGES
• High speed • High pressure capability • No overhung bearing loads • Design accommodates wide
variety of materials • Sections can be stacked for
multiple inlets and outlets • Bi-Directional
• Four bushings in liquid area • No solids allowed • Fixed end clearances
Calgary Pump Symposium 2013
External Gear Pump Performance Range
FLOW RANGE 0.001 TO 1500 GPM
VISCOSITY RANGE
0.1 cPs - 1,000,000 cPs
MAXIMUM DIFFERENTIAL PRESSURE 3000 PSI (20,000 kPa)
TEMPERATURE RANGE -100°F to 500°F (-80°C to 260°C)
Calgary Pump Symposium 2013
Example Applications
Fuel oil & Lube oil filtering, dewatering, and dispensing
Calgary Pump Symposium 2013
Example Applications
Injection of additives into pipeline. (i.e. dyes, mercaptum, etc.)
Calgary Pump Symposium 2013
Example Applications
Acid or caustic transfer (composite pump)
Calgary Pump Symposium 2013
Example Applications
Duplex fuel oil skids for backup power gen sets or burner systems
Calgary Pump Symposium 2013
Example Applications
Rust preventative or lube oil delivery to multiple points with a single pump
Calgary Pump Symposium 2013
Vane Pumps
Calgary Pump Symposium 2013
Vane Pump Operating Principle
Calgary Pump Symposium 2013
Vane Pump Operating Principle
Calgary Pump Symposium 2013
How the Vanes Work
1. Push rods initiate the vane extension when the opposing vane is pushed into its slot.
2. Centrifugal force, slings the vanes to the outside.
Calgary Pump Symposium 2013
How the Vanes Work
1. Push rods initiate the vane extension when the opposing vane is pushed into its slot.
2. Centrifugal force, slings the vanes to the outside.
3. Grooves in each vane’s leading edge allow liquid to feed in under pressure to push behind the vane.
Calgary Pump Symposium 2013
Self Compensating for Wear
Calgary Pump Symposium 2013
Vane Pump Advantages
ADVANTAGES DISADVANTAGES
• Sliding contact of vanes make this pump good for thin liquids
• Can run dry for short periods • Pump normally has one seal
chamber
•Can have two seal chambers •Not suitable for high
pressures •Not suitable for high viscosity •Not good with abrasives •Failure mode is catastrophic
when vanes fail
Calgary Pump Symposium 2013
Vane Pump Performance Range
FLOW RANGE 5 to 2000 GPM
VISCOSITY RANGE 0.1 cPs – 25,000 cPs
MAXIMUM DIFFERENTIAL PRESSURE
150 PSI (1000 kPa)
TEMPERATURE RANGE -60°F to 225°F (-50°C to 110°C)
Calgary Pump Symposium 2013
Example Applications
Propane, Butane, Liquid CO2, and other liquefied gases.
Calgary Pump Symposium 2013
Example Applications
Water
Calgary Pump Symposium 2013
Lobe Pumps
Calgary Pump Symposium 2013
Lobe Pump Operating Principle
Calgary Pump Symposium 2013
Lobe Profiles
Bi-Wing (or Scimitar) Tri-Lobe Multi-Lobe Multi-Lobe
(SIP)
Twin-Wing Rotor Single-Wing Rotor
Calgary Pump Symposium 2013
Lobe Pump Advantages
ADVANTAGES DISADVANTAGES
• Pass medium solids • No metal-to-metal contact • Superior CIP/SIP
capabilities • Long term dry run (with
lubrication to seals)
• Requires timing gears • Requires two seals • Reduced lift with thin
liquids
Calgary Pump Symposium 2013
Lobe Pump Performance Range
FLOW RANGE 5 to 800 GPM
VISCOSITY RANGE
0.1 cPs – 1,000,000 cPs
MAXIMUM DIFFERENTIAL PRESSURE 400 PSI (2800 kPa)
TEMPERATURE RANGE -40°F to 400°F (-40°C to 200°C)
Calgary Pump Symposium 2013
Example Applications
• Sanitary • Food • Personal Care • Pharmaceutical
• Industrial • Chemical • Pulp and Paper
• Municipal • Sludge • Slurry
Calgary Pump Symposium 2013
Example Applications
Wax in shale oil refinery
Calgary Pump Symposium 2013
Hydraulically Actuated Diaphragm Pumps
Calgary Pump Symposium 2013
Diaphragm Pump Operating Principle
Calgary Pump Symposium 2013
Diaphragm Pump Advantages
ADVANTAGES DISADVANTAGES
• No shaft seal required • High pressure capability • Excellent metering capability • Variable flow (either
mechanically or speed) • High temperature capacity
•Pulsing flow •Internal hydraulic system to
maintain •Potential for contamination
when diaphragm fails •High cost, especially for large
flows
Calgary Pump Symposium 2013
Diaphragm Pump Performance Range
FLOW RANGE 0.001 to 70 GPM
VISCOSITY RANGE 0.1 cPs – 10,000 cPs
MAXIMUM DIFFERENTIAL PRESSURE
6000 PSI (40,000 kPa)
TEMPERATURE RANGE -60°F to 800°F (-50°C to 425°C)
Calgary Pump Symposium 2013
Example Applications
Polymer metering
Calgary Pump Symposium 2013
Air Operated Diaphragm Pumps
Calgary Pump Symposium 2013
AOD Pump Operating Principle
Calgary Pump Symposium 2013
AOD Pump Operating Principle
Calgary Pump Symposium 2013
Is an AOD a PD pump or not?
Calgary Pump Symposium 2013
AOD Pump Advantages
ADVANTAGES DISADVANTAGES
• No shaft seal required • Portable • Handles solids and abrasives • Can run dry • Easy to run • Explosion proof • Inexpensive
•Pulsing flow •Inconsistent flow due to
system changes •May be expensive to operate •Diaphragm failure causes
immediate leakage •Limited diaphragm life due to
constant flexing •Discharge pressure limited by
air pressure
Calgary Pump Symposium 2013
Diaphragm Pump Performance Range
FLOW RANGE 0.5 to 300 GPM
VISCOSITY RANGE 0.1 cPs – 17,500 cPs
MAXIMUM DIFFERENTIAL PRESSURE
125 PSI (850 kPa)
TEMPERATURE RANGE -40°F to 212°F (-40°C to 100°C)
Calgary Pump Symposium 2013
Example Applications
Waste water / sludge
Calgary Pump Symposium 2013
Comparison of Technologies
Principle High Flows Low Flows High Pressure High Temperature
Internal Gear 1600 GPM 0.5 GPM 400 PSI 800°F
External Gear 1500 GPM 0.001 GPM 3000 PSI 500°F
Vane 2000 GPM 5 GPM 150 PSI 225°F
Lobe 800 GPM 5 GPM 400 PSI 400°F
3 Screw 3400 GPM 1 GPM 4500 PSI 500°F
2 Screw 5000 GPM 20 GPM 1500 PSI 650°F
Progressive Cavity 2400 GPM 1 GPM 1500 PSI 350°F
Hydraulic Diaphragm 70 GPM 0.001 GPM 6000 PSI 800°F
Air Diaphragm (AOD) 300 GPM 0.5 GPM 125 PSI 212°F
Calgary Pump Symposium 2013
Comparison of Technologies
Principle High Viscosity Low Lubricity Dry Run Multiphase
Internal Gear Excellent Good Short No
External Gear Excellent Good Short No
Vane Fair Excellent Short No
Lobe Excellent Excellent Yes Yes
3 Screw Good Poor Short No
2 Screw Good Excellent Yes Yes
Progressive Cavity Excellent Good No Yes
Hydraulic Diaphragm Fair Excellent Yes Yes
Air Diaphragm (AOD) Fair Excellent Yes Yes
Calgary Pump Symposium 2013
Comparison of Technologies
Principle Abrasive Liquids Liquids w/ Solids Shear Sensative
Internal Gear Yes No Yes
External Gear No No No
Vane No No No
Lobe Yes Yes Yes
3 Screw No No No
2 Screw Yes Yes Yes
Progressive Cavity Yes Yes Yes
Hydraulic Diaphragm Yes Yes Yes
Air Diaphragm (AOD) Yes Yes Yes
Calgary Pump Symposium 2013
Comparison of Technologies
Principle Smooth Output Sealless Option Sanitary Option
Internal Gear Steady Output Yes Yes
External Gear Steady Output Yes NSF Options
Vane Steady Output Yes NSF Options
Lobe Slight Pulsing No Yes
3 Screw Steady Output Yes No
2 Screw Steady Output No Yes
Progressive Cavity Steady Output No Yes
Hydraulic Diaphragm Pulsed Output Inherently Sealless Yes
Air Diaphragm (AOD) Pulsed Output Inherently Sealless Yes
Calgary Pump Symposium 2013
Other Considerations For Selection
• Frequency of maintenance and ease of repair • Spare part consistency/availability • Mechanical Efficiency • Total cost of ownership
Calgary Pump Symposium 2013
Thank You
• UNDERSTAND LIQUID CHARACTERISTICS
• UNDERSTAND THE PUMPING SYSTEM
• UNDERSTAND THE PUMP PRINCIPLE