Difference Between ANSI & API Pumps

Parameters

 ANSI  ANSI B73. 1 for horizontal end suction suction top

Type Pump and

discharge pump.

Specification

 ANSI 73.! for "ertical In#line pumps. pumps.  All are single stage.

 API  API $1% for horizontal single single and multlstage pumps. "ertical in#line& "crtical single& and multistage centrifugal pumps.

'a(imum

'inimum 7%% PSl0

 Allo)a*le +or,ing !7/ PSI0

Some API pumps are designed for pressure

Pressure -'A+P

a*o"e /%% PSI0.

ydrostatic Test Pressure

lange 4ating

'a(imum Temperature 'aterials of :onstructions -:asing and Impeller

'inimum 1%/% PSI0 21/ PSI0

 API pump hydrostatic test pressure pressure )ill *e 1./ times the 'A+P.

1/%5 flat faced is standard. 1/%5 raised face is a"aila*le. !S89

3%%5 raised face is standard. $%%& 6%%& 1/%% and higher ratings are a"aila*le if reuired *y the ser"ice. %%9

Pump casing is foot mounted )hich limits Pump casing is centerline mounted. No casing allo)a*le thermal gro)th ;uctile Iron 31$SS  Alloy !%  A car*on steel casing or impeller impeller is not commonly a"aila*le //% to $%% feet

'a(imum ead

 ANSI pumps are only single single stage.

;ifferential

'a(imum impeller diameter is a*out 13 inches. 8pen impellers are common. Some

thermal gro)th limitations. :ar*on steel casing is standard. Stainless steel is also a"aila*le. Impelller materials are cast iron& car*on steel& and stainless steel. Practical limit is 1%%%% feet. orizontal API pumps can ha"e as many as 12 stages.  All are enclosed design. Some open designs designs are

Impeller ;esign and enclosed impellers are a"aila*le.

a"aila*le for special co,e crushing ser"ices.

 Attachment

Impellers must *e ,ey dri"en )ith a loc, nut

No standard for attachment to the shaft.

'ost are threaded on the end of the shaft. attachment. Standard

 ANSI pumps are *uilt for

;imensions

interchangea*ility *et)een manufacturers. Not reuired *ut are a"aila*le. it to the

Shaft Sle"es

shaft and e(tension past the gland are not  ANSI specification reuirements. reuirements.


:an *e grease or oil lu*ricated.

No standard dimensions apply.  Are reuired to pre"ent shaft damage in the the scal or pac,ing area. Slee"e and stuffing *o( design is part of the  API $1% specification. 8il lu*rication is reuired. =sually ring oil system is pro"ided.

 Antifriction *all *earings must *e duple(& Thrust *earing and
 Antifriction *earings only. B#1% *earing life of 17/%% hours at design load is reuired.

single ro)& 2%#degree angular#contact type& installed *ac, to *ac,. <#1% *earing life must e(ceed !/&%%% hours at rated condition& or 1$&%%% hours at ma(imum a(ial and radial loads at rated speed.

 +ear 4ings

Not reuired and not a"aila*le in most designs due to the use of open impellers.

:ase and impeller& front and *ac, )ear rings are reuired. +ear ring clearences& attachment and hardness differential are specified.

Concl usi on:API compl i antpumpsar eal waysabet t erchoi cet hanANSIorI SO pumps