ANSI vs. API pump O&M

[geauxdeep]

does anyone have any insight into O&M cost differences between ANSI and API pumps and what aspects may play a role into higher costs for one over the other. thanks in advance.

 

[vpl]

take a look at thread407-170147 and see if it answers your questions.

Patricia Lougheed

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[TenPenny]

If you are running a high speed / high temp / high horsepower service, you'll likely find that the API pump is more robust = longer life, = lower maintenace costs.

If you are running at, say, 1800 rpm speeds, less than 300 deg F temps, 200 hp and below, you'll find the ANSI pumps are 'probably' less expensive to maintain.

As a rough (very rough) guide, you could expect that, for example, an impeller for an API pump will be 2-4 times the cost of a similar sized ANSI pump. (this guesstimate may be revised tomorrow when I'll be at work and have something more than my memory to go by).

 

[TenPenny]

To add further, comparing say a 2x3-10 ANSI pump to a 2x4-9 API pump, in basic iron/steel construction, the API impeller is 4-6 times the cost of the ANSI impeller, and the API shaft is 3-4 times.

Referring to the 'Pump User's Handbook' by Bloch and Budris, this question is addressed, with the answer that:

"Unless flammable, toxic, or explosion-prone liquids are involved, many carefully selected, properly installed, operated, and maintained ANSI or ISO pumps may represent an uncompromising and satisfactory choice."

 

[PumpSmart]

geauxdeep,
Key of API pumps is Reliability. It supports more higher
working pressures (has an 300# flanges as standar),
more higher temperatures (due to the construction material
,high grade carbon steel or its centreline design in OH2 type that does not permit that thermal expansion reduces its aligment and life. API pumps could support extreme conditions you need it or not.
API pumps design is compromising to have 3 years of continue interrupted operation and at least 20 years of expected cycle life.

Key of ANSI pumps is Flexibility and standarization.

API Pumps 8th were design for Petroleum Refining Industry.
API Pumps 9th and 10th were design for Gas /Petroleum Refining and General Industry.

If you analize cost-effective API pump use, you may consider if pump has a main process application, if it is consider a critical production equipment.

Some parameters helps to identify why API pumps are more reliable. L10 of bearings, L3/d4 of shaft,maximum working pressure rates, construction material, maximum working temperature, barepump weight, impeller balance tolerances, quality control, rating flanges, maximum overall vibration expected.