Parameters
Type Pump and
Specification
ANSI
API
ANSI B73. 1 for horizontal end suction top
API 610 for horizontal single and multlstage
discharge pump.
pumps. vertical in-line, vcrtical single, and
ANSI 873.2 for vertical In-line pumps.
multistage centrifugal pumps.
All are single stage.
Maximum
Allowable Working 275 PSIG
Pressure (MAWP)
Minimum 700 PSlG
Some API pumps are designed for pressure
above 500 PSIG.
Hydrostatic Test
Pressure
415 PSIG
Minimum 1050 PSIG
API pump hydrostatic test pressure will be 1.5
times the MAWP.
Flange Rating
150# flat faced is standard. 150# raised
face is available.
300# raised face is standard.
600, 900, 1500 and higher ratings are
available if required by the service.
Maximum
Temperature
2SO°F
800°F
Pump casing is foot mounted which limits Pump casing is centerline mounted. No casing
allowable thermal growth
thermal growth limitations.
Materials of
Constructions
(Casing and
Impeller)
Ductile Iron
316SS
Alloy 20
A carbon steel casing or impeller is not
commonly available
Carbon steel casing is standard.
Stainless steel is also available.
Impelller materials are cast iron, carbon steel,
and stainless steel.
Maximum Head
Differential
550 to 600 feet
ANSI pumps are only single stage.
Maximum impeller diameter is about 13
inches.
Practical limit is 10000 feet.
Horizontal API pumps can have as many as 14
stages.
Impeller Design
and Attachment
All are enclosed design. Some open designs
Open impellers are common. Some
are available for special coke crushing
enclosed impellers are available.
services.
No standard for attachment to the shaft.
Impellers must be key driven with a lock nut
Most are threaded on the end of the shaft.
attachment.
Standard
Dimensions
ANSI pumps are built for
interchangeability between
manufacturers.
Shaft Sleves
Not required but are available. Fit to the Are required to prevent shaft damage in the
shaft and extension past the gland are not scal or packing area.
ANSI specification requirements.
Sleeve and stuffing box design is part of the
No standard dimensions apply.
API 610 specification.
Lubrication
Can be grease or oil lubricated.
Oil lubrication is required. Usually ring oil
system is provided.
Antifriction ball bearings must be duplex,
single row, 40-degree angular-contact type,
Antifriction bearings only.
Thrust bearing and
installed back to back.
B-10 bearing life of 17500 hours at design
Life
L-10 bearing life must exceed 25,000 hours at
load is required.
rated condition, or 16,000 hours at maximum
axial and radial loads at rated speed.
Wear Rings
Not required and not available in most
designs due to the use of open impellers.
Case and impeller, front and back wear rings
are required. Wear ring clearences,
attachment and hardness differential are
specified.
Conclusion : API-compliant pumps are always a better choice than ANSI or ISO pumps
0
