CONTENTS
1. Scope ……………………………………………………….
2. Reference Documents …………………………..
2.1 SABIC Specifications …………………………..
2.2 Industry Codes and Standards …………………………..
3. Definitions……………………………………………………….
4. Design ……………………………………………………….
4.1 Pump Standard Application …………………………..
4.2 Rated Operating Conditions …………………………..
4.3 Hydraulic Performance …………………………..
4.4 Casing Design …………………………..
4.5 Heating / Cooling Jacket …………………………..
4.6 Shaft Sealing …………………………..
4.7 Bearings and Bearing Housings …………………………..
4.8 Materials of Construction …………………………..
4.9 Couplings and Guards …………………………..
4.10 Mounting Plates …………………………..
4.11 Drivers……………………………………………………….
4.12 Steam Turbines …………………………..
4.13 Energy Evaluations …………………………..
4.14 Piping ……………………………………………………….
4.15 Utilities ……………………………………………………….
5. Installation……………………………………………………….
6. Testing and Inspection …………………………..
7. Mechanical Seal Selection Guide …………………………..
Revision History……………………………………………………………………
1. Scope
This Standard defines the minimum requirements governing the design of pumping systems
that use centrifugal pumps.
2. Reference Documents
The selection of material and equipment and the design, construction, maintenance and
repair of equipment and facilities covered by the following SABIC Standards and shall comply
with the latest edition of the references listed below, unless otherwise noted.
2.1 SABIC Specifications
2.1.1 G01-S03 Horizontal End Suction Centrifugal Pumps for Chemical Process
2.1.2 G01-S04 Design of ASME B73.1 and General Purpose Baseplates
2.1.3 G01-S05 Vertical In-Line Pumps for Chemical Process
2.1.4 G01-S06 Centrifugal Pumps for Petroleum, Petrochemical and Natural Gas Industries
2.1.5 G01-S07 Horizontal Centrifugal Pumps for Water Service
2.1.6 G01-S08 Sealless Centrifugal Pumps
2.1.7 G01-S09 Vertical Centrifugal Pumps for Water Service
2.1.8 G01-G01 Guidelines for Pump Minimum Flow Protection
2.1.9 G01-T01 Centrifugal Pumps Inspection & Testing
2.1.10 G02-S01 Shaft Sealing System for Centrifugal & Rotary Pumps
2.1.11 G06-S01 General Purpose Steam Turbines
2.1.12 G20-C01 Installation of Machinery and Criteria for Installation Design
2.1.13 G23-E02 Typical Process Piping Arrangements to Pumps and Compressors
2.2 Industry Codes and Standards
2.2.1 American Petroleum Institute
a. API 610: Centrifugal Pumps for Petroleum, Petrochemical and Natural Gas
Industries
b. API 682: Pumps – Shaft Sealing Systems for Centrifugal and Rotary Pumps
c. API 685: Sealless Centrifugal Pumps for Petroleum, Heavy Duty Chemical,
and Gas Industry Services
2.2.2 International Organization for Standardization (ISO)
a. ISO 5199 Technical Specifications for Centrifugal Pumps Class II
b. ISO 2858 End-Suction Centrifugal Pumps (rating 16 bar) Designation,
Nominal duty point and dimensions
2.2.3 National Fire Protection Association
NFPA 20 Standard for the Installation of Stationary Pumps for Fire Protection
3. Definitions
Chemical Service. Any process service that does not contain hydrocarbons. This excludeswater services.
Flammable Service. Any product that will burn at it’s operating temperature and pressure.
Water Service. Any service that contains only water and does not contain hydrocarbons or
chemicals. The water stream can contain trace chemicals, such as those found in boiler feed
water and condensate services.
Secondary Leakage Containment. A combination of devices that in the event of leakage
from the primary containment shell, confines the pumped liquid within a secondary pressurecasing that includes provisions to indicate a failure of the primary containment shell.
Unit Responsibility. As defined in API-610 10
th
edition paragraph 3.55
4. Design
4.1 Pump Standard Application
4.1.1 Chemical Service pumps shall comply with Standard G01-S03, HorizontaEnd Suction Centrifugal Pumps for Chemical Process or G01-S05, VerticaIn-Line Pumps for Chemical Process. The limitations on using these
Standards are:
a. Discharge pressure does not exceed 1900 kPa(g) (275 psig)
b. Suction pressure does not exceed 500 kPa(g) (75 psig)
c. The temperature of the pumped liquid is not less than -40 °C and
does not exceed 149 °C
d. The vapor pressure of the pumped liquid is less than 100 kPa (14.
psia) at 66 °C
e. The driver nameplate rating (excluding any service factor) does
not exceed 112 kW (150 h.p.).
Note: When space limitations do not permit the use of horizontal pumps,
vertical in-line pumps complying with G01-S05 are acceptable.
If any one of above limitations is not met, the pump shall comply with SES
G01-S06 (which is SABIC’s exceptions and additions to API 610).
4.1.2 Pumps complying with ISO 5199/ ISO 2858 may be used for Chemical
Service subject to prior approval by SABIC. The first choice for ChemicalService is pumps complying with G01-S03 or G01-S05.
4.1.3 Pump in services containing hydrocarbon or flammable liquids shall comply
with SABIC Standard G01-S06, Centrifugal Pumps for Petroleum,
Petrochemical and Natural Gas Industries. The only exceptions shall be
vertical suspended pumps in sump service that have driver ratings not
exceeding 37 kW (50 h.p.).
4.1.4 Centrifugal pumps for Water Service including condensate, cooling water,
demineralized water, utility water, produced water, treated water and fire
water service shall comply with SABIC Standard G01-S07, Horizontal
Centrifugal Pumps for Water Services or for vertical pumps, SABIC Standard
G01-S09, Vertical Centrifugal Pumps for Water Services. The limitations on
using these Standards are:
a. Discharge pressure does not exceed 3500 kPa(g) (500 psig)
b. The temperature of the pumped liquid is not less than 0 °C and
does not exceed 120 °C
c. Maximum rotational speed is 3600 r/min or less
d. The driver nameplate rating (excluding any service factor) does
not exceed 750 kW (1000 h.p.).
e. Pump services that exceed the above limits shall be supplied in
accordance with SABIC Standard G01-S06.
4.1.5 Horizontal Centrifugal pumps for services that cannot be sealed with
conventional mechanical seals for example: Acetic Anhydride, Acids (Acetic,
Acrylic, Chloro-sulfuric, Formic, Hydrochloric, Hydrobromic, Nitric,
Phosphoric, and Sulfuric), Acrolein, Ammonium Chloride, Amines, Aniline,
Bromine, Carbon Tetrachloride, Chlorine, Chlorine Dioxide, Chloroform,
Caustics, Chlorinated solvents, Chloroform, Dichlorobenzene, Ethers,
Epichlorohydrin, Ethyl Acetate, Ethylene Dichloride, Formarin, Freon,
Hydrogen Cyanide, Hydrogen Peroxide, Iso Butylalcohol, Iso-propyl alcohol,
Maleic anhydride, Oleum, Perchloroethylene, Phosgene, Potassium
Hydroxide, Silicon oil, Silicon Tetrachloride, Sodium Hypochlorite, Titanium
Tetrachloride, Trichlorethylene, and Vinyl Acetate and shall comply with G01S08
provided
that:
a. Discharge pressure does not exceed 1900 kPa(g) (275 psig);
b. Suction pressure does not exceed 500 kPa(g) (75 psig);
c. The temperature of the pumped liquid is not less than -40 °C and
does not exceed 149 °C; With SABIC approval the maximum
temperature can be increased to 260 °C.
d. The driver nameplate rating (excluding any service factor) does
not exceed 112 kW (150 h.p.).
e. Pumped fluid does not contain any magnetic particles.
f. Magnetic drive sealless pumps or canned motor sealless pumps
shall be provided when secondary leakage containment is not
required. If secondary leakage containment is required, canned
motor sealless pumps shall be provided.
g. Magnetic drive pumps shall be provided with a temperature
indicator and switch for pump shutdown on high containment shell
temperature. Canned motor pumps shall be provided with a
bearing wear monitor and switch for pump shutdown on excessive
bearing wear.
h. Sealless Pumps which exceed the above limits shall comply with
API-685 Sealless Centrifugal Pumps for Petroleum, Heavy Duty
Chemical, and Gas Industry Services.
4.1.6 Horizontal Pumps are preferred for all applications. Vertical pumps shall be
applied for sump service, for low NPSH applications where all attempts to
design for a horizontal pump have been exhausted, where space limitations
are a consideration, or in cooling tower basins.
4.1.7 Pumps in firewater service shall comply with the requirements of NFPA 20.
4.1.8 Vendor’s standard design shall be provided when:
a. Vertical suspended pumps having driver ratings not exceeding 37
kW (50 h.p.) are in sump service;
b. Horizontal self priming pumps are in sump service with a suction
lift not exceeding 5 m and a rated capacity not exceeding 110
m
3
/h. (500 USGPM);
c. Pumps that are in domestic sewage service
4.1.9 When selecting pumps, the availability of spare parts of identical pumps
already in satisfactory operation shall be taken into account in the final
selection.
4.1.10 Unit responsibility for the complete pump train including driver, gear, oil
system(s) etc. shall be assigned to the pump manufacturer. An exception is
allowed when the driver is a diesel engine, special purpose steam turbine or
combustion gas turbine.
4.1.11 Pump Summary Table
4.2 Rated Operating Conditions
4.2.1 The NPSHA at 100 percent of rated flow shall be determined from the
maximum liquid temperature with corresponding vapor pressure.
4.2.2 Viscosity correction factors shall be applied. Refer to the Hydraulic Institute
Standard. Extrapolation is not recommended. Correction factors for water are
1:1:1. Limitations on use of viscous liquid performance correction chart are:
a. Use only for pumps of conventional hydraulic design, in the
normal operating range, with open or closed impellers. DO NOT
use for mixed flow or axial flow pumps or for pumps of special
hydraulic design for either viscous or non-uniform liquids.
b. Use only on Newtonian (uniform) liquids. Gels, slurries and other
non-uniform liquids may produce widely varying results,
depending on the particular characteristics of the liquids.
4.2.3 When determining the rated suction pressure, the minimum expected suction
pressure shall be specified.
4.3 Hydraulic Performance
4.3.1 NPSH: Pumps that are required to be NSPH tested will be evaluated before
purchase. The pump vendor shall submit references for pumps with similar conditions
and shall submit NPSH test data for previously built pumps.
4.3.2 For high energy or high performance pumps strong emphasis shall be placed
on evaluation of Vendor’s references for similar impellers operating
successfully under similar conditions and/or verification of the 40,000 hours
NPSH curve. The first stage impeller inlet geometry and rated operating
conditions shall be submitted, together with the Vendor’s references for
similar impellers, to SABIC for approval. Pumps shall be considered subject
to this review when any of the following conditions apply:
a. The first stage is of high energy design, as defined by API
610, paragraph 5.1.18
4.4 Casing Design
b. The peripheral eye velocity of the first stage impeller
exceeds 30 m/s (98.4 ft/s)
4.4.1 The maximum allowable working pressure of horizontal and vertical in-line
pump casings shall be at least equal to the sum of the maximum suction
pressure and the differential pressure developed at shut-off with the
furnished impeller diameter installed at maximum specific gravity and at
maximum speed.
4.4.2 Casing design temperature shall be at least equal to the specified maximum
flow temperature, as a minimum.
4.4.3 The maximum allowable working pressure (MAWP) of the bowl assembly,
column assembly and discharge head of vertical suspended pumps shall be
at least equal to the maximum differential pressure developed by the bowl
assembly at shut-off with furnished impeller diameter installed at maximum
specific gravity and at maximum speed.
4.5 Heating / Cooling Jacket
4.5.1 Pumps shall have a heating/cooling jacket if conditions require it.
Comment: The following are the types of jackets typically used on centrifugal
pumps:
a. Stuffing Box Jacket
b. Seal Chamber Jacket (Fully Jacketed Only)
c. Pump Casing Jacket
d. Bolt On or External Steam Jacket (Casing)
e. Bearing Housing Cooling Jacket (Oil sump fin tube is preferred)
Cast bearing housing jackets are acceptable only with SABIC’s approval.
Comment: Jackets are used to remove or add heat to the local area to which
they are applied. High temperature liquids that flash if heat is added, such as
through rubbing friction or mechanical seals, require cooling. High
temperature liquids that solidify if the temperature decreases require the
addition of heat, especially during startup when piping and pumps are at
ambient temperature. It is advisable to hydrostatically test jackets prior to
shipping the pump. Leakage to the atmosphere could be hazardous in some
processes.
4.5.2 Use of a heating/cooling jacket shall be considered for the following
conditions:
a. Temperature of pumped fluid above 150 °C (300 °F) unless metal
bellow type seals are used
b. Temperature of pumped fluid above 300 °C (572 °F)
c. Boiler feed water pumps
d. Dead-ended seal chambers
e. Low flash point liquids
f. High melting point products
4.5.3 Cooling/heating jackets or inserts for seal chambers shall be provided by the
pump vendor if specified by the purchaser.
4.5.4 If the temperature of the pumped fluid is greater than 175 °C (350 °F), the
pump and seal vendors shall be jointly consulted about using cooled flush or
running the seal chamber dead-ended with jacket cooling.
4.5.5. Cooling/heating jackets for seal chambers shall have connections arranged
so that the entire passageway can be mechanically cleaned, flushed, and
drained.
4.6 Shaft Sealing – Mechanical Seals
4.6.1 There are three mechanical seal categories that are acceptable:
a. Mechanical Seals that are required to be in full compliance with
SABIC Standard G02-S01 and API-682. These mechanical seals
are designated as 682-FC Seals. Pumps which comply with G01S06
and
G15-S01
will
require
682-FC
seals
for
specified
services.
b. Mechanical Seals that are supplied to meet the intent of G02-S01
and API-682. These seals are designated as 682-I mechanical
seals.
c. Non-compliant 682 mechanical seals or 682-NC seals. The
mechanical seals furnished for G01-S03, G01-S05, G01-S07 and
G01-S09 shall meet the requirements of each individual standard.
Manufacturer’s standard pumps shall be furnished with the pump
suppliers standard mechanical seal.
4.6.2 The following paragraphs of G02-S01 and API-682 are amended as follows:
a. Para 2.2.2: Heat generation and heat soak calculations are not
required to be submitted to SABIC.
b. Para 2.2.3 Mechanical seal thrust loads are not required.
c. Para 2.3.19.1 Process side gland connections shall be either ½”
or ¾”.
d. Para 2.3.20 Throttle bushings are not required for dual seals.
e. Section 4
All accessories and piping shall be in accordance with API-610 10
edition.
f. Para 4.6.2.1 System resistance curves are not required for
submittal to SABIC.
g. Para 4.6.2.2 Internal circulating device flow curves are not
required to be submitted to SABIC.
h. Para 6.3.1 All seals shall be pre-qualified. No further qualification
tests are required. The seal vendor shall supply a certifcation, that
the seal was qualification tested, qualification test results are not
to be submitted to SABIC.
i. Para 6.3.2.1 Mechanical Seal Glands manufactured from cast
materials shall be hydrostatically tested. All other seal glands are
exempted from hydrotest.
j. Para 6.3.3 & 6.3.4 These paragraphs are deleted. All mechanical
seals are required to have an air test as described in API-610
paragraph 7.3.3.5.d. This air test is not optional.
k. Section 7 – Manufacturer Data
Para 7.2 The only proposal data required by SABIC is the mechanical
seal model proposed and a statement that the seal has been
qualification tested.
Para 7.3 The contract data required is items a, b, and d. See Appendix C
or API-682 for the data sheet to be submitted after the pump order has
been placed.
4.6.3 The Mechanical Seal Guide provides initial selections for some Process
Services, and is intended as an initial selection guide only. All parties
involved in the Seal Selection process, the Process Licensor, Engineering
Contractor , Pump Supplier, Mechanical Seal supplier and SABIC are all
responsible for the final Mechanical Seal selection. The Pump Supplier has
unit responsibility to review the liquid properties, and to supply the correct
Mechanical Seal.
When applying the Mechanical Seal Selection Guide, the following shall be
observed:
a. Seal and auxiliary systems for the various liquids pumped are specified
in order of preference.
b. Seal leakage systems, when required by service conditions, are included
in the scope of supply of the pump Vendor unless otherwise specified.
c. True vapor pressure is the vapor pressure at pump operating
temperature;
d. The classification code in this guide is based on API 682, 3rd edition.
The API 610 10th edition code is also shown.
4.6.4 Packing is required for main firewater service and for slurry service. Pumps
in oily water or storm water sump service may be provided with packing.
4.7 Bearings and Bearing Housings
4.7.1 Bearings shall be oil lubricated unless exempt from the scope of G01-S03,
G01-S05, G01-S06, G01-S07, G01-S08 or G01-S09. In addition, pure or
purge mist lubrication may be applied, when ten or more pumps (excluding
pumps having pressure lubrication) are located within a 50 m radius of the oil
mist generator.
Anti-friction bearings of pumps exempt from these specifications may be
grease lubricated if Vendor’s standard.
4.7.2 The up thrust and down thrust values for vertical pumps quoted by the
Vendor shall be the maximum forces expected at any point on the full pump
curve.
It shall be verified that the values listed are within the bearing design criteria
of the driver or transmission unit which absorbs the rotor thrust.
4.8 Materials of Construction
4.8.1 Metallurgy for pumps supplied in accordance with G01-S06 shall be specified
and supplied using ASTM material grades as outlined in API-610 tables H-2
and H-3. Materials listed by other designations in table H-3 are also
acceptable. Alternate materials not listed in table H-2 are acceptable, if they
are designated as ASTM materials.
4.8.2 Metallurgy for pumps supplied in accordance with G01-S03, G01-S05, G01S07,
G01-S08
and
G01-S09
shall
be
supplied
using
ASTM
material
grades.
4.8.3 In case of a material offering which does not comply with ASTM designation,
SABIC shall be consulted to ensure that the alternate material offering is at
least equal to or better than specified.
4.8.4 Materials of construction for special fluids may be based on information
provided in publications, recommendations provided by pump manufacturers
or other accepted sources. In such cases the material selection as proposed
by the manufacturer shall be approved by SABIC.
4.8.5 Substitution of equivalent or superior materials shall be approved by SABIC,
for any requested materials substitution. Sufficient data shall be provided by
the Vendor to justify the substitution. This data shall include but shall not be
limited to physical, mechanical and corrosion resistance properties.
4.9 Couplings and Guards
4.9.1 Lubricated couplings are not permitted.
4.9.2 For horizontal pumps, flexibly coupled vertical in-line pumps (except those
driven by reciprocating engines or synchronous electric motors), and vertical
suspended pumps having thrust bearings, flexible disc pack or diaphragm
type couplings are required.
4.9.3 Rigid adjustable spacer type couplings are required for vertical line shaft
pumps not equipped with thrust bearings.
4.9.4 Elastomeric type couplings or couplings having comparable torsional
stiffness are required for pumps driven by reciprocating engines and may be
considered for pumps driven by synchronous electric motors. Elastomeric
members shall not deteriorate due to exposure to a hydrocarbon
environment. Elastomeric members shall be confined upon coupling failure.
4.10 Mounting Plates
A baseplate is required for all horizontal pumps, a soleplate or baseplate shall be
supplied for all vertical pumps. G01-S06 baseplates and soleplates shall comply with
API 610. G01-S03 compliant pumps shall be supplied with baseplates in accordance
with G01-S04. A soleplate shall be supplied for pumps complying with G01-S09. A
baseplate or soleplate is not required for pumps complying with G01-S05. A
baseplate in accordance with SES G01-S04 shall be supplied for magnetic drive
pumps complying with SES G01-S08.
4.11 Drivers
4.11.1 Electric Motors
4.11.2 For applications in which the pumped fluid has a variable specific gravity, the
rated power of the motor shall be based on the greatest specific gravity.
4.11.3 If viscosity corrections for the pumped fluid are required, the power
requirements specified in sections 4.11.5, 4.11.6, and 4.11.7 shall be
increased an appropriate amount by the pump vendor. Start-up at cold
temperature, when the viscosity of the pumped fluid is higher than under
operating conditions, shall be taken into consideration.
4.11.4 Use of a variable speed motor may be considered under one or more of the
following circumstances:
a. Increasing flow rates cause increasing system resistance.
b. In slurry service when reduction in pump speed reduces erosion
and eliminates throttling valves.
c. Process does not require a constant head, which is typically
controlled by throttling.
Comment: The primary benefit of variable speed pumps is the reduction of
energy requirements due to the elimination of throttling and minimizing
erosion in slurry pumps. Variable speed pumps in constant head system
service have no advantage.
4.11.5 If the end-of-curve power is less than 4 kW (5 h.p.) the next standard size
larger motor shall be used.
Comment: The purpose of this requirement is to overcome startup problems
due to slow acceleration of small motors in overcoming inertia and drag of
seals. Seal drag increases as suction pressures increase. Failure to consider
these factors can result in tripping the driver before operating speed is
reached.
4.11.6 If the end-of-curve power is between 5.6 kW (7.5 h.p.) and 75 kW (100 h.p.),
motor shall be sized to cover the full operating range of the rated impeller
from shutoff to the end-of-curve without the use of a service factor. End-ofcurve
power
is
defined
as
120%
of
BEP.
4.11.7 If the end-of-curve power is greater than 75 kW (100 h.p.), the motor shall be
sized to cover the end-of-curve power or 110% of rated power, whichever is
less. For applications that are expected to operate at the end-of- curve, such
as cooling water circulating pumps, motors shall be sized to operate at the
end-of-curve.
4.11.8 Motor and coupling shall be sized to meet any known future increase in
power or head requirements. Future increase in head requirement shall be
able to be met with a larger diameter impeller.
4.11.9 Motor shall have adequate power for initial run-in on water with the pump
throttled to 50% of rated capacity. If this requirement results in an increase in
motor size, the larger motor shall be quoted as an alternate.
Comment: The purpose of this requirement is to verify that the motor is
adequately sized for water runs. However, if a larger motor must be furnished
solely for water runs, it should first be verified that a water run is planned,
and if so, alternate methods of accomplishing the water run should be
investigated before deciding to use the larger motor. If water runs are not
planned for startup, other methods of ensuring cleanliness of the system
must be used such as a blowdown with compressed air.
4.12 Steam Turbines
4.12.1 Steam turbine drivers shall conform to SABIC Standard G06-S01.
4.12.2 Steam turbine power rating shall be 110% of the calculated rated power of
the pump unless otherwise specified.
4.13 Energy Evaluations
4.13.1 Selection of pumps and drivers shall take into consideration cost of energy in
the plant in which they are to be installed along with a payout period
consistent with the design life defined in the project premises.
4.13.2 Efficiency of pump/driver used for the above selection shall be the efficiency
that occurs at the normal operating flow rate and at the resulting head for the
diameter of the impeller selected. Hours per year of pump operation shall
reflect the design stream factor.
4.14 Piping
All pumps except pumps complying with G01-S09 shall be supplied with a drain
connection. The drain valve does not need to be supplied by the pump vendor. Pump
vent piping is only required where the pump is not self-venting. Drain and/or vent
piping shall be within the confines of the baseplate. Services for which the pump
Vendor could supply such provisions are toxic liquids or liquids which could vaporize
at atmospheric conditions, thereby creating a potential flammable hazard.
4.15 Utilities
The cooling water supply conditions shall be made available. Inlet temperature,
maximum return temperature, normal (minimum) return pressure, and maximum
allowable pressure drop shall be specified. The Vendor shall complete the remaining
information.
5. Installation
5.1 Pumps shall be installed in accordance with SABIC Standard G20-C01, Installation of
Machinery and Criteria for Installation Design.
5.2 Pump suction and discharge piping shall comply with SABIC Standard G23-E02,
Typical Process Piping Arrangements, to pumps and compressors.
5.3 Pumps shall be located for convenience of process, operating and maintenance
requirements. The pump train arrangement shall ensure safe and easy access to all
equipment train components for operation and maintenance purposes.
5.4 Provisions for isolation, venting and draining the pump shall be installed to permit
internal inspection, repair or dismantling.
5.5 When more than one identical pump train is required, the design of the equipment
trains within the Vendor’s scope of supply, the auxiliary baseplate(s), the connecting
piping, cabling, wiring etc. shall be identical in layout, construction and accessibility.
5.6 Auxiliary lube oil systems for pumps and spare pumps shall be designed with the
same layout and with identical equipment.
5.7 The Vendor’s General Arrangement (G.A.) or outline drawings shall include all data
required to install the pump on its foundation. In addition to nozzles, shaft centerline
and baseplate foundation bolt coordinates, it shall contain coordinates of all
connections to be hooked up at site such as auxiliary piping connections, main and
auxiliary power terminal boxes etc. G.A. drawings shall also show Buyer’s references
and the main rating data of equipment components.
6. Testing and Inspection
Test Requirements For Centrifugal Pumps (1)
Notes:
1. These test requirements apply only to pumps supplied by Vendors known to
the Buyer. Pumps ordered from new sources shall be fully witness tested and
inspected except for pumps listed in Column 1, Manufacturers Standard.
2. If specified on the data sheet the hydrotest will be witnessed.
3. If specified on the data sheet the performance test will be witnessed.
4. All NPSH tests will be witnessed along with the corresponding performance
test.
5. An NPSH test is required if the NPSH margin is less than 0.9 meters (3 ft.).
6. If more than one pump on the same Purchase Order of identical type, design
and design conditions are presented for inspection as a lot, the test
requirements shall be as follows:
(i) For low energy pumps, one pump, selected at random
shall be fully witness tested. The remaining pumps
shall be fully shop tested and test certificates shall be
provided;
(ii) For high energy pumps, as defined by API 610 10th
Edition, paragraph 5.1.18, all pumps shall be fully
witness tested.
7. Open pit sump pumps require a minimum submergence test in lieu of an
NPSH test.
7. Mechanical Seal Selection Guide
Non-Flashing Hydrocarbon Service
Hazardous Hydrocarbon Service- Xylene, toluene, acetone, benzene, furfural, MEK, cumene
Sulfuric Acid Concentrated
Hydrofluoric Acid
Slurries
Seal Selection Guide Notes:
Note 1: Type A seals represent the minimum acceptable seal for these services. A bellows
seal is an acceptable alternative to the standard Type A seal in applications where
the maximum seal chamber pressure does not exceed 1830 kPa(a) (265 psia).
Justification for the selection of a bellows seal instead of a pusher seal for low
temperature services may include standardization with existing seal installations,
good operating experience with similar seals, elimination of the dynamic “O”ring
secondary seal, eliminating the stepped shaft sleeve, eliminating the requirement for
an overlaid shaft sleeve under the dynamic “O”ring, Vendor technical support, and
price.
Note 2: If a Plan 32 fluid is not available, then Plan 31 is required provided that the pump
differential pressure exceeds 175 kPa (25 psi). If Plan 32 is not available and the
pump differential pressure is less than 175 kPa (25 psi), seal flush plan 11 shall be
used.
Note 3: Plan 23 or 32 shall be used if the fluid may flash.
Note 4: Open-lineshaft vertical suspended pumps shall be provided with a seal flush Plan 13
or 32.
Note 5: If a compatible external source flush fluid (Plan 32) is not available, Plan 21 is
required if no suspended solids are present and Plan 41 is required if suspended
solids are present.
Note 6: For services which require dual seals, the primary seal will be either a Dry Running
Seal (DRS) as the back up seal or a full size primary and secondary seal such as AAP
design.
Note 7: Raw water quench is not intended to be continuous. Piping to be installed as a
branch off the seal flush line with a dead-man valve downstream of the tee to the
quench connection.
Note 8: Seal leakage from plan 52 shall be piped to the flare header. The seal leakage
detection pressure switch, orifice, and check valve shall be installed in the piping to
the flare. The check valve shall be installed downstream of the orifice and pressure
switch to prevent flow from the flare header into the seal chamber.
Note 9: Exchanger should be designed to maintain the flush fluid at or below 60 °C.
Note10: A methanol drip feed piping system, Plan 51, is only required on services when the
normal operating temperature of the pumped liquid is 0 °C and lower. The methanol
feed system is not intended to provide a continuous flow of methanol. It is used
immediately prior to start-up to prevent or eliminate icing on the atmospheric side of
the primary seal.
Note11: Open lineshaft design, vertical suspended pumps in raw water or seawater lift service
shall be provided with a bleed type discharge head bushing and a labyrinth seal
instead of a mechanical seal. If a labyrinth seal is not available, then grease
lubricated packing may be used.
Note12: The fourth letter (Z) in the API 610 seal code for Type C seals, BSTZN designates a
spiral wound gasket for the stationary seal ring gasket and graphite foil for the seal
ring-to-sleeve gasket. Substituting graphite foil for the stationary seal ring gasket is
acceptable.
General Mechanical Seal Notes:
1. The API-682 designation is the seal type as defined in API-682, with
subsequent letters that call out special features.
2. Rotating faces for low temperature service shall be of homogeneous
construction. (No weld overlays).
3. Cyclone separators shall not be used with a pressure differential less than
175 kPa (25 psi).
4. External flush fluids shall be considered when the liquid pumped has
suspended solids that will shorten seal life or when the pumped fluid tends to
crystallize at atmospheric conditions.
5.
a. Seal leakage detection is required for any of the following:
(i) Single seal with auxiliary dry running backup seal;
(ii) Dual seals.
b. A pressure switch shall be used for leakage detection of single seals
with auxiliary dry running backup seals. For dual seal applications,
either a pressure or a level switch may be used.
c. Pressure switches and level switches shall be designed to actuate
alarm and/or shutdown. The proof-rating of the pressure or level
switch must be 1.5 times the maximum seal chamber pressure.
d. The setting of the pressure switch shall be 35 kPa(g) (5 psig), unless
otherwise specified by the manufacturer.
e. In case of excessive leakage or failure of the mechanical seal, alarm
and/or shutdown actuation for the different type of seals shall be as
follows:
f. A 30 second time delay to actuate a shutdown will be applied. The
time delay relay is not included in the pump Vendor’s scope of
supply.
6. The use of Arrangement 2, dual seals, should be considered when:
a. Liquid pumped tends to crystallize or form carbon build up at
atmospheric conditions and no suitable quench is available;
b. The seal chamber pressure is exceeds 5170 kPa(g) (750 psig).
7. The use of Arrangement 3, dual seals, is required in services that are toxic
and should be considered when the liquid pumped is heavily contaminated
and no clean external flush is available.
8. On pump services supplied with a Plan 53 barrier fluid system, the minimum
pressure rating of the pressurized, barrier fluid system including the liquid
reservoir shall be at least 50 psi above the maximum seal chamber pressure.
Barrier fluid systems shall comply with the requirements of API 610, unless
other wise specified.
Non-pressurized, buffer fluid systems (Plan 52) shall have the vent connection
at the top of the reservoir connected to flare header. Buffer fluid systems shall
comply with API-610 unless otherwise specified.
9. With the exception of seal springs, all process wetted metal components of
seals shall be 316 L SS.
a. Metal parts not in contact with the medium pumped shall be
316 SS.
b. If bellows seals are provided, the bellows material shall be
Inconel 625 or 718.
c. Seal springs shall be of Hastelloy C-276.
10. Water shall not be used in seal chamber cooling jackets but may be used for
mechanical seal quench in non-hydrocarbon service.
11. Water or air cooled seal flush plans shall not be used if the viscosity of the
pumped fluid at ambient temperature exceeds 500 SSU (110 cSt). Instead,
steam shall be used in the seal chamber jacket and, if required, to maintain a
low viscosity seal flush fluid. A needle valve shall be provided in the steam
piping upstream of the pump seal chamber jacket or exchanger connections to
ensure superheated steam and minimize steam usage. An example of a
service that would use steam in the jacket would be asphalt.