EN ISO 13709:2009

SLOVENSKI STANDARD
01-februar-2010
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SIST EN ISO 13709:2004
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Centrifugal pumps for petroleum, petrochemical and natural gas industries (ISO
13709:2009)
Kreiselpumpen für den Einsatz in der Erdöl-, petrochemischen und Erdgasindustrie (ISO
13709:2009)
Pompes centrifuges pour les industries du pétrole, de la pétrochimie et du gaz naturel
(ISO 13709:2009)
Ta slovenski standard je istoveten z: EN ISO 13709:2009
ICS:
23.080 ýUSDONH Pumps
75.180.20 Predelovalna oprema Processing equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN ISO 13709
NORME EUROPÉENNE
EUROPÄISCHE NORM
December 2009
ICS 71.120.99; 75.180.20 Supersedes EN ISO 13709:2003
English Version
Centrifugal pumps for petroleum, petrochemical and natural gas
industries (ISO 13709:2009)
Pompes centrifuges pour les industries du pétrole, de la Kreiselpumpen für den Einsatz in der Erdöl-,
pétrochimie et du gaz naturel (ISO 13709:2009) petrochemischen und Erdgasindustrie (ISO 13709:2009)
This European Standard was approved by CEN on 10 October 2009.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the CEN Management Centre or to any CEN member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as the
official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2009 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 13709:2009: E
worldwide for CEN national Members.

Contents Page
Foreword .3

Foreword
This document (EN ISO 13709:2009) has been prepared by Technical Committee ISO/TC 115 "Pumps" in
collaboration with Technical Committee CEN/TC 12 “Materials, equipment and offshore structures for
petroleum, petrochemical and natural gas industries” the secretariat of which is held by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by June 2010, and conflicting national standards shall be withdrawn at
the latest by June 2010.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 13709:2003.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
Endorsement notice
The text of ISO 13709:2009 has been approved by CEN as a EN ISO 13709:2009 without any modification.

INTERNATIONAL ISO
STANDARD 13709
Second edition
2009-12-15
Centrifugal pumps for petroleum,
petrochemical and natural gas industries
Pompes centrifuges pour les industries du pétrole, de la pétrochimie et
du gaz naturel
Reference number
ISO 13709:2009(E)
©
ISO 2009
ISO 13709:2009(E)
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©  ISO 2009
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
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Published in Switzerland
ii © ISO 2009 – All rights reserved

ISO 13709:2009(E)
Contents Page
Foreword .v
Introduction.vi
1 Scope.1
2 Normative references.1
3 Terms and definitions .4
4 General .11
4.1 Unit responsibility .11
4.2 Classification and designation .11
5 Requirements.18
5.1 Units.18
5.2 Statutory requirements.18
5.3 Requirements.19
6 Basic design .19
6.1 General .19
6.2 Pump types .23
6.3 Pressure casings.24
6.4 Nozzles and pressure casing connections.27
6.5 External nozzle forces and moments .30
6.6 Rotors .37
6.7 Wear rings and running clearances .38
6.8 Mechanical shaft seals.39
6.9 Dynamics.43
6.10 Bearings and bearing housings.56
6.11 Lubrication .61
6.12 Materials .61
6.13 Nameplates and rotation arrows.66
7 Accessories .67
7.1 Drivers .67
7.2 Couplings and guards.70
7.3 Baseplates.71
7.4 Instrumentation .74
7.5 Piping and appurtenances.74
7.6 Special tools .76
8 Inspection, testing, and preparation for shipment .76
8.1 General .76
8.2 Inspection.77
8.3 Testing.79
8.4 Preparation for shipment.86
9 Specific pump types.87
9.1 Single-stage overhung pumps.87
9.2 Between-bearings pumps (types BB1, BB2, BB3 and BB5) .88
9.3 Vertically suspended pumps (types VS1 through VS7) .93
10 Vendor's data .99
10.1 General .99
10.2 Proposals .100
10.3 Contract data .103
ISO 13709:2009(E)
Annex A (informative) Specific speed and suction-specific speed .105
Annex B (normative) Cooling water and lubrication system schematics.106
Annex C (normative) Hydraulic power recovery turbines.115
Annex D (normative) Standard baseplates.119
Annex E (informative) Inspector's checklist.121
Annex F (normative) Criteria for piping design .123
Annex G (informative) Materials class selection guidance.137
Annex H (normative) Materials and material specifications for pump parts .139
Annex I (normative) Lateral analysis.147
Annex J (normative) Determination of residual unbalance .154
Annex K (informative) Shaft stiffness and bearing system life .160
Annex L (informative) Vendor drawing and data requirements .166
Annex M (informative) Test data summary.175
Annex N (informative) Pump datasheets and electronic data exchange.179
Bibliography .181

iv © ISO 2009 – All rights reserved

ISO 13709:2009(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 13709 was prepared by Technical Committee ISO/TC 115, Pumps, Subcommittee SC 3, Installation and
special application, in collaboration with Technical Committee ISO/TC 67, Materials, equipment and offshore
structures for petroleum, petrochemical and natural gas industries, SC 6, Processing equipment and systems.
This second edition cancels and replaces the first edition (ISO 13709:2003), which has been technically
revised.
ISO 13709:2009(E)
Introduction
It is necessary that users of this International Standard be aware that further or differing requirements can be
needed for individual applications. This International Standard is not intended to inhibit a vendor from offering,
or the purchaser from accepting, alternative equipment or engineering solutions for the individual application.
This can be particularly appropriate where there is innovative or developing technology. Where an alternative
is offered, it is necessary that the vendor identify any variations from this International Standard and provide
details.
A bullet ( ) at the beginning of a clause or subclause indicates that either a decision is required or the
purchaser is required to provide further information. It is necessary that this information should be indicated on
data sheets or stated in the enquiry or purchase order (see examples in Annex N).
In this International Standard, where practical, US Customary, or other, units are included in parentheses for
information.
vi © ISO 2009 – All rights reserved

INTERNATIONAL STANDARD ISO 13709:2009(E)

Centrifugal pumps for petroleum, petrochemical and natural
gas industries
1 Scope
This International Standard specifies requirements for centrifugal pumps, including pumps running in reverse
as hydraulic power recovery turbines, for use in petroleum, petrochemical and gas industry process services.
This International Standard is applicable to overhung pumps, between-bearings pumps and vertically
suspended pumps (see Table 1). Clause 9 provides requirements applicable to specific types of pump. All
other clauses of this International Standard are applicable to all pump types. Illustrations are provided of the
various specific pump types and the designations assigned to each specific type.
Relevant industry operating experience suggests pumps produced to this International Standard are cost
effective when pumping liquids at conditions exceeding any one of the following:
. discharge pressure (gauge) 1 900 kPa (275 psi; 19,0 bar)
. suction pressure (gauge) 500 kPa (75 psi; 5,0 bar)
. pumping temperature 150 °C (300 °F)
. rotative speed 3 600 r/min
. rated total head 120 m (400 ft)
. impeller diameter, overhung pumps 330 mm (13 in)
NOTE For sealless pumps, reference can be made to API Std 685. For heavy duty pump applications in industries
other than petroleum, petrochemical and gas processing, reference can be made to ISO 9905.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 7-1, Pipe threads where pressure-tight joints are made on the threads — Part 1: Dimensions, tolerances
and designation
ISO 228-1, Pipe threads where pressure-tight joints are not made on the threads — Part 1: Dimensions,
tolerances and designation
ISO 261, ISO general purpose metric screw threads — General plan
ISO 262, ISO general purpose metric screw threads — Selected sizes for screws, bolts and nuts
ISO 281:2007, Rolling bearings — Dynamic load ratings and rating life
ISO 13709:2009(E)
ISO 286 (all parts), ISO system of limits and fits
ISO 724, ISO general-purpose metric screw threads — Basic dimensions
ISO 965 (all parts), ISO general-purpose metric screw threads — Tolerances
ISO 1940-1, Mechanical vibration — Balance quality requirements for rotors in a constant (rigid) state —
Part 1: Specification and verification of balance tolerances
ISO 3117, Tangential keys and keyways
ISO 4200, Plain end steel tubes, welded and seamless — General tables of dimensions and masses per unit
length
ISO 5753, Rolling bearings — Radial internal clearance
ISO 7005-1, Metallic flanges — Part 1: Steel flanges for industrial and general service piping systems
ISO 7005-2, Metallic flanges — Part 2: Cast iron flanges
ISO 8501 (all parts), Preparation of steel substrates before application of paints and related products — Visual
assessment of surface cleanliness
1)
ISO 9606 (all parts), Approval testing of welders — Fusion welding
2)
ISO 9906, Rotodynamic pumps — Hydraulic performance acceptance tests
ISO 10438:2007 (all parts), Petroleum, petrochemical and natural gas industries — Lubrication, shaft-sealing
and control-oil systems and auxiliaries
ISO 10441, Petroleum, petrochemical and natural gas industries — Flexible couplings for mechanical power
transmission — Special-purpose applications
ISO 10721-2, Steel structures — Part 2: Fabrication and erection
ISO 11342, Mechanical vibration — Methods and criteria for the mechanical balancing of flexible rotors
ISO 14120, Safety of machinery — Guards — General requirements for the design and construction of fixed
and movable guards
ISO 14691, Petroleum, petrochemical and natural gas industries — Flexible couplings for mechanical power
transmission — General-purpose applications
ISO 15156-1, Petroleum and natural gas industries — Materials for use in H S-containing environments in oil
and gas production — Part 1: General principles for selection of cracking-resistant materials
ISO 15609 (all parts), Specification and qualification of welding procedures for metallic materials — Welding
procedure specification
ISO 15649, Petroleum and natural gas industries — Piping
ISO/TR 17766, Centrifugal pumps handling viscous liquids — Performance corrections
ISO 21049:2004, Pumps — Shaft sealing systems for centrifugal and rotary pumps

1) Some parts of ISO 9606 are under revision and some revised parts have been published with Qualification test of
welders as the main title.
2) To be published. (Revision of ISO 9906:1999)
2 © ISO 2009 – All rights reserved

ISO 13709:2009(E)
IEC 60034-1, Rotating electrical machines — Part 1: Rating and performance
IEC 60034-2-1, Rotating electrical machines — Part 2-1: Standard methods for determining losses and
efficiency from tests (excluding machines for traction vehicles)
3)
IEC 60079 (all parts), Electrical apparatus for explosive gas atmospheres
EN 953, Safety of machinery — Guards — General requirements for the design and construction of fixed and
movable guards
EN 13445 (all parts), Unfired pressure vessels
EN 13463-1, Non-electrical equipment for use in potentially explosive atmospheres — Part 1: Basic method
and requirements
ANSI/ABMA 7, Shaft and Housing Fits for Metric Radial Ball and Roller Bearings (Except Tapered Roller
4)
Bearings) Conforming to Basic Boundary Plan
5)
ANSI/AGMA 9000, Flexible Couplings — Potential Unbalance Classification
ANSI/AGMA 9002, Bores and Keyways for Flexible Couplings (Inch Series)

6)
ANSI/AMT B15.1, Safety Standard for Mechanical Power Transmission Apparatus
ANSI/API Std 541, Form-Wound Squirrel-Cage Induction Motors — 500 Horsepower and Larger
ANSI/API Std 611, General-Purpose Steam Turbines for Petroleum, Chemical, and Gas Industry Services
ANSI/API Std 670, Machinery Protection Systems
ANSI/API Std 671/ISO 10441, Special Purpose Couplings for Petroleum, Chemical and Gas Industry Services
7)
ANSI/ASME B1.1, Unified Inch Screw Threads, UN and UNR Thread Form
ANSI/ASME B16.1, Gray Iron Pipe Flanges and Flanged Fittings: Classes 25, 125 and 250
ANSI/ASME B16.5, Pipe Flanges and Flanged Fittings: NPS 1/2 through NPS 24 Metric/Inch Standard
ANSI/ASME B16.11, Forged Steel Fittings, Socket-Welding and Threaded
ANSI/ASME B16.42, Ductile Iron Pipe Flanges and Flanged Fittings, Classes 150 and 300
ANSI/ASME B16.47, Larger Diameter Steel Flanges: NPS 26 Through NPS 60
ANSI/ASME B18.18.2M, Inspection and Quality Assurance for High-Volume Machine Assembly Fasteners
ANSI/ASME B31.3, Process Piping
8)
ANSI/HI 1.6, Centrifugal Tests

3) Many parts of this standard have Explosive atmospheres as the main title.
4) American Bearing Manufacturers Association, 2025 M Street, NW, Suite 800, Washington, DC 20036, USA.
5) American Gear Manufacturers Association, 1500 King Street, Suite 201, Alexandria, VA 22314, USA.
6) American National Standards Institute, 1819 L Street, Suite 600, Washington, D.C. 20036, USA.
7) American Society of Mechanical Engineers, Three Park Avenue, New York, NY 10016-5990, USA.
8) Hydraulic Institute, 9 Sylvan Way, Parsippany, NJ 07054, USA.
ISO 13709:2009(E)
ANSI/HI 2.6, American National Standard for Vertical Pump Tests
API Std 547, General-Purpose Form-Wound Squirrel Cage Induction Motors — 250 Horsepower and Larger
API Std 677, General-Purpose Gear Units for Petroleum, Chemical and Gas Industry Services
ASME, Boiler and pressure vessel code BPVC, Section V, Nondestructive Examination
ASME, Boiler and pressure vessel code BPVC, Section VIII, Rules for Construction of Pressure Vessels
ASME, Boiler and pressure vessel code BPVC, Section IX, Welding and Brazing Qualifications
9)
DIN 910, Heavy-duty hexagon head screw plugs
IEEE 841, IEEE Standard for Petroleum and Chemical Industry — Severe Duty Totally Enclosed Fan-Cooled
10)
(TEFC) Squirrel Cage Induction Motors — Up to and Including 500 hp
MSS SP-55, Quality Standard for Steel Castings for Valves, Flanges and Fittings and Other Piping
11)
Components — Visual Method for Evaluation of Surface Irregularities
NACE MR0103, Materials Resistant to Sulfide Stress Cracking in Corrosive Petroleum Refining
12)
Environments
13)
NFPA 70:2008, National Electrical Code
14)
SSPC SP 6, Commercial Blast Cleaning
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
axially split
split with the principal joint parallel to the shaft centreline
3.2
allowable operating region
portion of a pump's hydraulic coverage over which the pump is allowed to operate, based on vibration within
the upper limit of this International Standard or temperature rise or other limitation, specified by the
manufacturer
3.3
barrel pump
horizontal pump of the double-casing type

9) Deutsches Institut für Normung, Burggrafenstrasse 6, Berlin, Germany D-10787.
10) Institute of Electrical & Electronics Engineers, 445 Hoes Lane, Piscataway, NJ 08855-1331, USA.
11) Manufacturers Standardization Society of The Valve and Fittings Industry Inc., 127 Park Street N.E., Vienna,
VA 22180-4602, USA.
12) National Association of Corrosion Engineers, Houston, Texas, USA.
13) National Fire Protection Association, 1 Batterymarch Park, Quincy, MA 02269-9101, USA.
14) Society for Protective Coatings, 40 24th Street, 6th Floor, Pittsburgh, PA 15222-4643, USA.
4 © ISO 2009 – All rights reserved

ISO 13709:2009(E)
3.4
barrier fluid
externally supplied fluid, at a pressure above the pump seal chamber pressure, introduced into an
Arrangement 3 seal (pressurized dual mechanical seal) to completely isolate the pump process liquid from the
environment
3.5
best efficiency point
BEP
flowrate at which a pump achieves its highest efficiency at rated impeller diameter
NOTE The best efficiency point flowrate at maximum impeller diameter is used to determine pump specific speed
and suction specific speed. The best efficiency point flowrate at reduced impeller diameters is similarly reduced from the
value at maximum impeller diameter.
3.6
buffer fluid
externally supplied fluid, at a pressure lower than the pump seal chamber pressure, used as a lubricant and/or
to provide a diluent in an Arrangement 2 seal (unpressurized dual mechanical seal)
3.7
cartridge-type element
assembly of all the parts of the pump except for the casing
3.8
classically stiff
characterized by the first dry critical speed being above the pump's maximum continuous speed by the
following:
20 % for rotors designed for wet running only
30 % for rotors designed to be able to run dry
3.9
critical speed
shaft rotational speed at which the rotor-bearing-support system is in a state of resonance
3.10
datum elevation
elevation to which values of NPSH are referred (see 6.1.8)
cf. net positive suction head (3.33)
3.11
design
manufacturer's calculated parameter
NOTE “Design” is a term that may be used by the equipment manufacturer to describe various parameters, such as
design power, design pressure, design temperature, or design speed. This term should be used only by the equipment
manufacturer and not in the purchaser's specifications.
3.12
double casing
type of pump construction in which the pressure casing is separate from the pumping elements contained in
the casing
NOTE Examples of pumping elements include diffuser, diaphragms, bowls and volute inner casings.
ISO 13709:2009(E)
3.13
drive-train component
item of the equipment used in series to drive the pump
EXAMPLES Motor, gear, turbine, engine, fluid drive, clutch.
3.14
dry critical speed
rotor critical speed calculated assuming that there are no liquid effects, that the rotor is supported only at its
bearings and that the bearings are of infinite stiffness
3.15
element
bundle
assembly of the rotor plus the internal stationary parts of a centrifugal pump
3.16
hydraulic power recovery turbine
HPRT
turbomachine designed to recover power from a fluid stream
3.17
hydrodynamic bearing
bearing that uses the principles of hydrodynamic lubrication
3.18
identical pump
pump of the same size, hydraulic design, number of stages, rotational speed, clearances, type of shaft seal
(axial face or breakdown bushing), type of bearings, coupling mass, coupling overhang, and pumping the
same liquid
3.19
maximum allowable speed
highest speed at which the manufacturer's design permits continuous operation
3.20
maximum allowable temperature
maximum continuous temperature for which the manufacturer has designed the pump (or any part to which
the term is referred) when pumping the specified liquid at the specified maximum operating pressure (does not
include mechanical seal)
cf. pressure casing (3.43)
3.21
maximum allowable working pressure
MAWP
maximum continuous pressure for which the manufacturer has designed the pump (or any part to which the
term is referred) when pumping the specified liquid at the specified maximum operating temperature (does not
include mechanical seal)
3.22
maximum discharge pressure
maximum specified suction pressure plus the maximum differential pressure the pump with the furnished
impeller is able to develop when operating at rated speed with liquid of the specified normal relative density
(specific gravity)
6 © ISO 2009 – All rights reserved

ISO 13709:2009(E)
3.23
maximum dynamic sealing pressure
highest pressure expected at the seals during any specified operating condition and during start-up and shut-
down
NOTE Both dynamic and static sealing pressures are important to selection of the mechanical seal. They are
dependent on the pump suction pressure, operating point and pump clearances. They are also affected by the pressure of
the seal flush. This pressure is specified to the seal vendor. See ISO 21049 or ANSI/API Std 682/ISO 21049.
3.24
maximum operating temperature
highest temperature of the pumped liquid, including upset conditions, to which the pump is exposed
NOTE This temperature is specified to the seal vendor. See ISO 21049 or ANSI/API Std 682/ISO 21049.
3.25
maximum static sealing pressure
highest pressure, excluding pressures encountered during hydrostatic testing, to which the seals can be
subjected while the pump is shut down
3.26
maximum suction pressure
highest suction pressure to which the pump is subjected during operation (non-transient; does not include
waterhammer)
3.27
minimum allowable speed
lowest speed at which the manufacturer's design permits continuous operation
NOTE The speed is expressed in units of revolutions per minute.
3.28
minimum continuous stable flow
lowest flow at which the pump can operate without exceeding the vibration limits imposed by this International
Standard
3.29
minimum continuous thermal flow
lowest flow at which the pump can operate without its operation being impaired by the temperature rise of the
pumped liquid
3.30
minimum design metal temperature
lowest mean metal temperature (through the thickness) expected in service, including operation upsets,
auto-refrigeration and temperature of the surrounding environment, for which the equipment is designed
3.31
multistage pump
pump with three or more stages
See 4.2.
3.32
nominal pipe size
NPS
designation, usually followed by a size designation number, corresponding approximately to the outside
diameter of the pipe
NOTE The NPS is expressed in inches.
ISO 13709:2009(E)
3.33
NPSH
net positive suction head
absolute inlet total head above the head equivalent to the vapour pressure referred to the NPSH datum plane
NOTE NPSH is expressed in metres (feet) of head of the pumped liquid.
3.34
net positive suction head available
NPSHA
NPSH determined by the purchaser for the pumping system with the liquid at the rated flow and normal
pumping temperature
3.35
net positive suction head required
NPSH3
NPSH that results in a 3 % loss of head (first-stage head in a multistage pump) determined by the vendor by
testing with water
3.36
normal operating point
point at which the pump is expected to operate under normal process conditions
3.37
normal-wear part
part normally restored or replaced at each pump overhaul
EXAMPLES Wear rings, inter-stage bushings, balancing device, throat bushing, seal faces, bearings and gaskets.
3.38
observed inspection
observed test
inspection or test where the purchaser is notified of the timing of the inspection or test and the inspection or
test is performed as scheduled, regardless of whether the purchaser or his representative is present
3.39
oil-mist lubrication
lubrication provided by oil mist produced by atomization and transported to the bearing housing, or housings,
by compressed air
3.40
operating region
portion of a pump's hydraulic coverage over which the pump operates
3.41
overhung pump
pump whose impeller is supported by a cantilever shaft from its bearing assembly
3.42
preferred operating region
portion of a pump's hydraulic coverage over which the pump's vibration is within the base limit of this
International Standard
3.43
pressure casing
composite of all stationary pressure-containing parts of the pump, including all nozzles, seal glands, seal
chambers and auxiliary connections but excluding the stationary and rotating members of mechanical seals
NOTE The atmospheric side of the seal gland, the seal flush (piping) plan, auxiliary piping and valves are not part of
the pressure casing.
8 © ISO 2009 – All rights reserved

ISO 13709:2009(E)
3.44
purchaser
owner, or owner's agent, who issues the order and specification to the vendor
3.45
pure oil-mist lubrication
〈dry sump〉 system in which the mist both lubricates the bearing(s) and purges the housing and there is no oil
level in the sump
3.46
purge oil-mist lubrication
〈wet sump〉 systems in which the mist only purges the bearing housing
3.47
radially split
split with the principal joint perpendicular to the shaft centreline
3.48
rated operating point
point at which the vendor certifies that pump performance is within the tolerances stated in this International
Standard
NOTE Normally, the rated operating point is the specified operating point with the highest flow.
3.49
relative density
specific gravity
property of a liquid expressed as the ratio of the liquid's density to that of water at standard temperature
NOTE Standard temperature is 4 °C (39,2 °F).
3.50
rotor
assembly of all the rotating parts of a centrifugal pump
3.51
similar pump
pump that is accepted, by agreement between purchaser and manufacturer as sufficiently similar to not
require a lateral analysis, taking into account the factors listed for an identical pump (3.18)
3.52
specific speed
index relating flow, total head and rotational speed for pumps of similar geometry
3.53
stage
one impeller and associated diffuser or volute and return channel, if required
3.54
suction-specific speed
index relating flow, NPSH3 and rotative speed for pumps of similar geometry
3.55
throat bushing
device that forms a restrictive close clearance around the sleeve (or shaft) between the seal or inner seal of a
dual seal cartridge and the impeller
ISO 13709:2009(E)
3.56
total indicator reading
total indicated runout
TIR
difference between the maximum and minimum readings of a dial indicator or similar device, monitoring a face
or cylindrical surface, during one complete revolution of the monitored surface
NOTE For a perfectly cylindrical surface, the indicator reading implies an eccentricity equal to half the reading. For a
perfectly flat face the indicator reading gives an out-of-squareness equal to the reading. If the diameter in question is not
perfectly cylindrical or flat, interpretation of the meaning of TIR is more complex and can represent ovality or lobing.
3.57
trip speed
〈electric motor driver〉 electric motor driver-synchronous speed at maximum supply frequency
3.58
trip speed
〈variable-speed driver〉 variable-speed driver-speed at which the independent emergency over-speed device
operates to shut down the driver
3.59
unit responsibility
responsibility for coordinating the documentation, delivery and technical aspects of the equipment and all
auxiliary systems included in the scope of the order
NOTE The technical aspects for consideration include, but are not limited to, such factors as the power requirements,
speed, rotation, general arrangement, couplings, dynamics, lubrication, sealing system, material test reports,
instrumentation, piping, conformance to specifications and testing of components.
3.60
vendor
supplier
manufacturer or manufacturer's agent that supplies the equipment and is normally responsible for service
support
3.61
vertical in-line pump
vertical-axis, single-stage overhung pump whose suction and discharge connections have a common
centreline that intersects the shaft axis
NOTE Types VS6 and VS7 are not considered in-line pumps.
3.62
vertically suspended pump
vertical-axis pump whose liquid end is suspended from a column and mounting plate
NOTE The pump's liquid end is usually submerged in the pumped liquid.
3.63
wet critical speed
rotor critical speed calculated considering the additional support and damping produced by the action of the
pumped liquid within internal running clearances at the operating conditions and allowing for stiffness and
damping within the bearings
3.64
witnessed test
witnessed inspection
inspection or test for which the purchaser is notified of the timing of the inspection or test and a hold is placed
on the inspection or test until the purchaser or his representative is in attendance
10 © ISO 2009 – All rights reserved

ISO 13709:2009(E)
4 General
4.1 Unit responsibility
Unless otherwise specified, the pump vendor shall have unit responsibility. The pump vendor shall ensure that
all sub-vendors comply with the requirements of this International Standard and all reference documents.
4.2 Classification and designation
4.2.1 Description of codes
The pumps described in this International Standard are classified and designated by type codes, as shown in
Table 1.
Table 1 — Pump classification type identification
Type
a
Pump type Orientation
code
Foot-mounted OH1
Horizontal
Centreline-
OH2
Flexibly coupled
supported
Vertical in-line with
— OH3
bearing bracket
Rigidly coupled Vertical in-line — OH4
Vertical in-line — OH5
Close-coupled
High-speed integrally
— OH6
geared
Axially split — BB1
1- and 2-stage
Radially split — BB2
Axially split — BB3
Multistage Single casing BB4
Radially split
Double casing BB5
Diffuser VS1
Discharge through
Volute VS2
column
Single casing Axial flow VS3
Line shaft VS4
Separate discharge
Cantilever VS5
Diffuser — VS6
Double casing
Volute — VS7
a
Illustrations of the various types of pump are provided in 4.2.2.
Centrifugal pumps
Vertically suspended Between-bearings Overhung

ISO 13709:2009(E)
4.2.2 Pump designations and descriptions
4.2.2.1 Pump type OH1
Foot-mounted, single-stage overhung pumps shall be designated pump type OH1. (This type does not meet
all the requirements of this International Standard; see Table 3.)

Figure 1 — Pump type OH1
4.2.2.2 Pump type OH2
Centreline-mounted, single-stage overhung pumps shall be designated pump type OH2. They have a single
bearing housing to absorb all forces imposed upon the pump shaft and maintain rotor position during
operation. The pumps are mounted on a baseplate and are flexibly coupled to their drivers.

Figure 2 — Pump type OH2
4.2.2.3 Pump type OH3
Vertical, in-line, single-stage overhung pumps with separate bearing brackets shall be designated pump
type OH3. They have a bearing housing integral with the pump to absorb all pump loads. The driver is usually
mounted on a support integral to the pump. The pumps and their drivers are flexibly coupled.

Figure 3 — Pump type OH3
12 © ISO 2009 – All rights reserved

ISO 13709:2009(E)
4.2.2.4 Pump type OH4
Rigidly coupled, vertical, in-line, single-stage overhung pumps shall be designated pump type OH4. Rigidly
coupled pumps have their shaft rigidly coupled to the driver shaft. (This type does not meet all the
requirements of this International Standard; see Table 3.)

Figure 4 — Pump type OH4
4.
...