gary fitch, alan hopewell & john e. · pdf filegary fitch gary has 20 years experience in...

Calgary Pump Symposium 2013

Presentation / Course

Gary Fitch, Alan Hopewell &

John E. Sidelko


Calgary Pump Symposium 2013 Calgary Pump Symposium 2013

Gary Fitch Gary has 20 years experience in Hydraulic design and pump application. Previously Sulzer UK Hydraulic design manager, currently Advance Engineering manager Oil & Gas and HPI for Sulzer in Portland Oregon.

Alan Hopewell Alan has 25 years experience in Mechanical Design and Pump Application. Previously in the UK and for Sulzer in Burnaby, BC. Currently with Advance Engineering.

John E. Sidelko John has over 35 years of engineering experience with centrifugal pumps and compressors in areas of design, customer service, project management and engineering management. He represents Sundyne LLC as a member

of the API 610 Working Group.

Calgary Pump Symposium 2013 Calgary Pump Symposium 2013

HIGH-SPEED PUMPS

API TYPE BB3, BB5 & OH6


• Why Select a High-Speed Pump?

• How is the High-Speed Achieved?

• Typical Applications.

• Hydraulic Issues.

• Design Issues.

High-Speed Pumps : Topics


High-Speed Pumps: Why?

Concentrated Energy = Smaller Components

Ease of Maintenance

Fewer Stages

Reduced Pump Cost

Reduced Pump Footprint

High Impeller Tip Speed = High Differential Head

Power = T x N

Constant


High-Speed Pumps : Why?

Hydraulic Duty Condition - High Differential Head.

Affinity Laws

2

1

212

n

nHH

1

212

n

nQQ

• Simply put, if we double the speed the capacity will double but the head will increase to the square i.e., by a factor of 4.

• This permits us to attain very large heads for modest increases in flow.

• Incidentally, the power will also increase to the product of the above, a factor of 8. The NPSHR will also increase by a factor of 4 and may prompt the use of a booster pump.



Specific Speed Ns = RPM x GPM

Head.75



Increased Speed = Reduced Physical Size of Pump Reduced Pump Cost. Note: Pump Train Cost may Increase

Reduced Pump Space. Note: Pump Train Space will Increase


High-Speed Pumps : How?

Speeds in Excess of 3600 rpm Require Special Drives:

Electric Motor + Speed Increasing Gearbox

Engine + Speed Increasing Gearbox

Steam Turbine

Gas Turbine


High-Speed Pumps : Applications Applications where High Speed Pumps are Used:

Water Injection - Oil & Gas Industry

CO2 Injection - Oil & Gas Industry?

Boiler Feed Water - Power Industry

Hydrocarbon - Hydrocarbon Processing Industry

Ethane, Butane, Ethylene - Gas Processing Industry

Ammonia - Fertilizer Industry

Wash Water – Hydrocarbon Processing Industry


High-Speed Pumps : Applications


High-Speed Pumps : Speed Variation


High-Speed Pumps : NPSHA vs. NPSHR

NPSHR increases with rising peripheral

speed at the impeller eye. Bubble implosion on vane surface is more destructive

Infinite impeller life

40K HR Life

NPSHA to be above

40K HR Life prediction


NPSH margin guide : High Speed

APPLICATION

FLUID LOW/MEDIUM DUTY

<3600rpm

HIGH DUTY

>3600rpm

HYDROCARBON 1.1 1.3

AMINE 1.5 2.0

CARBONATE SOLUTIONS 1.5 2.0

WATER 1.3 1.6

PRODUCED WATER 1.6 2.0

BOILER FEED 1.6 2.5

MINIMUM MARGIN 0.6M TO 1.0M



S = SuctionSpecificSpeed

= Q N

NP SHR0.75

Axial Flow Impellers Achieve High Suction Specific Speed



Axial Flow Impellers Have “Sharp” Breakdown Curves

0

10

20

30

40

50

60

70

80

90

100

Stag

e 1

Dif

fere

nti

al H

ead

%

NPSH

NPSHR NPSHR

3% Drop

Gentle Breakdown - Impeller

Sharp Breakdown - Inducer



Axial Flow Impellers Have Less Operating Range Than Radial Flow Impellers

H

Q

Impeller

NPSH

Required

Inducer NPSH Required

Inducer

Operating

Range

BEP


High-Speed Pumps : Design Issues

Check Impeller Peripheral (tip) Velocity. • Above 250 ft./sec. – Upgrade Impeller to chrome (CA6NM).

• Above 300 ft./sec/ - Perform Impeller analysis to determine if Vanes or Shrouds need to be thickened,

including corner radii to avoid stress raisers.



Check clearance between Impeller O.D. and Case Volute Lip. • With head per stage > 600 ft. – 6% clearance is required.

• With speeds > 3600 rpm – 6 to 10% clearance is required.



Check Case Design Pressure. • Max. Disch. Press. = (New / Original Speed)2 x Shut-off Head x sp.gr./2.31 + Suction Pressure.

• A High Pressure Case Design may be required.

Check Shaft Torsional Stress. • Max. Power = (New / Original Speed)3 x Rated Power

• A Larger Shaft may be required.



Check Bearing Selection. • Antifriction Bearings will probably not work (too much heat generation).

• Sleeve Radial / Pivot-Shoe Thrust Bearings will probably be required.

• Pivot-Shoe Radial and Thrust Bearings will be required at Speeds > 6000 rpm.

{See next page}

Sleeve Radial / Pivot-Shoe Thrust

Antifriction Radial &Thrust



Pivot-Shoe Radial Bearing

Check Bearing Selection (continued).

• Pivot-Shoe Radial and Thrust Bearings will be required at Speeds > 6000 rpm.

Tilt pad Thrust bearing



Check Coupling Selection. • Must use a Low Mass Coupling.

• Consider a Reverse Moment Coupling Design.

• Avoid use of shaft keys if possible – Utilize a Hydraulic Fitted Coupling?

Hydraulic Fitted Coupling hub

Low Mass Diaphragm Coupling



Check Mechanical Seal Selection.

• Seal Design must be suitable for high speed. (Consider stationary flexible element).

Stationary Flexible Element


High-Speed Pumps : Design Issues Check Pump Throttle Bushing Location. • Orientate rotation to locate the throttle bushing at the drive end of the pump.

Minimize Shaft Extension Length

• (To minimize overhanging moment @ coupling).

Throttle Bushing



Utilize Integral Impeller Wear Rings - (if acceptable).

Consider Use of Precision Cast Impellers • (To minimize hydraulic turbulence

and mechanical imbalance).



Use Special Shaft Runout and Balancing Requirements. • See Engineering Design Manual for details.

Perform Lateral Analysis of Pump Rotor.


High-Speed Pumps : OH6 Hydraulic Range

Units SI U.S.

Capacities Up to 90 m3/h Up to 400 gpm

Heads Up to 1,920 m Up to 6,300 ft

Pressures Up to 248 bar Up to 3,600 psi

Temperature Up to 400oC Up to 750oF

Speeds Up to 24,500 rpm


High-Speed Pumps : OH6 Multi-Stage Range

Units SI U.S.

Capacities Up to 360 m3/h Up to 1,585 gpm






High-Speed Pumps : BB3 Hydraulic range

Units SI U.S.

Capacities Up to 740 m3/h Up to 3250 gpm






High-Speed Pumps : BB5 Hydraulic range

Units SI U.S.

Capacities Up to 300m3/h Up to 1,350 gpm



Temp Up to 427oC Up to 800oF



High-Speed Pumps : Hydraulic Ranges


High-Speed Pumps : Continuous Improvement CFD Analysis Adjusted To Match Hardware Results


High-Speed Pumps : Continuous Improvement

Relative Surface Velocities – Flow Fields Turbulent, Abrupt



Modified Vane Entrance – Flow Fields Merging



The resulting vectors are

smooth and remain attached

to the impeller surface.

Patent Pending -

Flow Vector Control


High-Speed Pumps : Continuous Improvement Patent Pending – Flow Vector Control


Installation China - VGO Recycle Pump

Problem Statement

Our customer is building a coal to liquids plant which requires a high pressure

pump delivering 233gpm (53m3/h) at 9,300 ft (2,835m) of head .

Challenges

•Low specific speed design requiring small hydraulic passageways

•Achieving casting tolerances required for success

•Required API hot clearances will

be a challenge for rotor dynamics

and efficiency


Installation China - VGO Recycle Pump

Solution

New High Speed Pump Design 4x4x9I CP 12stg

• Qty of 2 high speed BB5 pumps

• Single volute design with Quasi-Concentric geometry for improved radial load balance

• Precision cast volute inserts for improved performance control

• Rated speed 5,600rpm 1-Turbine drive and 1-Motor Drive

• 9,300ft head at 233 gpm (2835m head at 53m3/h) Ns = 582 (Nq = 11.2)

• Product temperature 294°F to 644°F (146°C to 340°C)

• 5430 psig (374bar) MAWP with 4" TechLoc flanges

• 8145 psig (562bar) Hydrostatic test

• Construction C-6 with integral wear rings


Installation China – Hydraulic Performance


Installation China – Drive Train

Rated speed 5,600rpm

• 1-Turbine drive

• 1-Motor Drive

Motor, Gearbox & Pump Drive Train

Steam Turbine & Pump Drive Train


Installation China – Drive Train


Installation China – Waterway Model

Short

Crossover

Volute

Volute

Insert Crossover

Suction End


Installation China – Insert to Case match

Insert sits in a circular

pocket machined from the

case split line


Installation China – Insert to Case match


Installation China – Volute Orientation • Stages are staggered in an over/under arrangement to help balance radial load

FL

OW

FL

OW


Installation China – Radial Thrust • Quasi-Concentric volutes are designed to balance radial load at closed valve and BEP.

0

0.2

0.4

0.6

0.8

1

1.2

0 0.2 0.4 0.6 0.8 1 1.2 1.4

Single Spiral

Concentric

Quasi-Concentric

Double Volute

RA

DIA

L T

HR

US

T

FLOW RATE

Be

st

Eff

icie

nc

y F

low

Ru

no

ut


Installation GOM : Offshore Oil Pipeline pump

Problem Statement

Customer needed high pressure oil treatment

pumps to deliver 1232 gpm (280m3/h) at 8425

ft (2,568m) of head for an integrated drilling

and production offshore platform.

Challenges

• Space constraints on offshore platforms.

• High speed compact design

• Harsh environment conditions


Installation GOM : Offshore Oil Pipeline pump

Solution New High Speed Pump Design

8x8x9CX CP 11stg

• Qty of 3 high speed BB5 pumps

• New hydraulic design

• Rated speed 6,500rpm

Voith Geared Fluid Coupling

• 8,425ft at 1232gpm Ns = 1567

2,568m at 280m3/h Nq = 30.3

• 4334 psig (300bar) MAWP

• 8310 psig (573bar) Hydrostatic test

• Construction S-6 with integral wear rings

• Non standard large shaft design

(3.38" vs. 2.68")

Voith Design

1 - Gear stage

2 - Hydrodynamic variable speed coupling

3 - Scoop tube

4 - Electro-hydraulic positioning control (VEHS)

5 - Working oil cooker

6 - Lube oil cooker

7 - Main lube oil pump

8 - Oil circulation control valve

9 - Working iol pump

10 - Auxiliary lube oil pump

11 - Duplex filter

12 - Oil reservoir


Installation GOM : Hydraulic Performance


High-Speed Pumps : OH6 Assembly


High-Speed Pumps : OH6 Multi-Stage


High-Speed Pumps : Train assembly


High-Speed Pumps : Thank you!

Gas Turbine Drive

gary fitch, alan hopewell & john e. · pdf filegary fitch gary has 20 years experience in...

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