7 replies to this topic

[ankur2061]

Dear All,

A frequent problem faced during FED (Front End Design) faced by process engineers is to sum up the requirement and provide line sizing for the cooling water requirements for pumps (API 610).

API 610 describes the following cooling plans for pumps based on its design for overhung pumps (the most ommon configuration):

Plan A: cooling to bearing housing
Plan D: gland quench
Plan K: cooling to bearing housing with parallel flow to seal heat exchanger
Plan M: cooling to seal heat exchanger

My question is are there any guidelines for considering CW flow rate for each of these plans or is it pump /seal manufacturer specific? If it is pump vendor and/or seal manufacurer specific, then is there a published and readily available data base of CW requirement for the various cooling plans provided by different manufacturers such as:

Flowserve (pumps)
Ebara (pumps)
Sulzer (pumps)
John Crane (Seals)
Burgmann (Seals)

The point here is that can I avoid waiting for specific vendor/manufacturer data for cooling water and use some generic data which is a fairly good approximation, for summing up my cooling water requirements and sizing for a plant/unit having say 100 pumps with various cooling plans depending on the pump type as specified in the pump data sheet?

Hope some learned members can shed some light on this.

Regards,
Ankur.

[ankur2061]

Art/Doug/Joe/Zauberberg,

Any thoughts or suggestions?

Regards,
Ankur.

[Qalander (Chem)]

Art/Doug/Joe/Zauberberg,

Any thoughts or suggestions?

Regards,
Ankur.

Sorry Dear ankur, As I could'nt dare suggesting what came in mind to support.

However now I may give my raw&lttle thoughts

1)It should be fairly clear how many pumps of what particular type/cooling plans? involved in the whole project.

2)Grouping similar needs/types e.g Seal oil, Jacket,shaft etc. cooling needs will help

3)generation of overall needs with around 10%~15% accuracy.

This value added with other areas cooling water needs may provide reasonable estimation of what you enquired.

Hope this humble info proves helpful.

Since now I usually abstain and wait for other forum giants to come forward for your help.

[ankur2061]

Dear Qalander,

Thanks for the insight. But I need some kind of numbers for the cooling water flow for each cooling plan. Maybe not exact values but a ±10% estimate would serve me fine.

If somebody has this kind of info or database, would greatly appreciate if he/she could share it.

Regards,
Ankur.

[ARAZA]

Dear Ankur,

I've tried looking up on the Goulds and the FLowserve websites but didn't any such data in which you are interested.

I would just call up the local vendors and give them the basis pump details and I'm sure they will throw more light on this issue.

In my experience, I've seen very often 1/2" and 3/4" once through cooling water line for such applications, these lines sizes would carry 5-8 gpm max. cooling water.

Hope this helps.

ARAZA

Dear Qalander,

Thanks for the insight. But I need some kind of numbers for the cooling water flow for each cooling plan. Maybe not exact values but a ±10% estimate would serve me fine.

If somebody has this kind of info or database, would greatly appreciate if he/she could share it.

Regards,
Ankur.

[riven]

The point here is that can I avoid waiting for specific vendor/manufacturer data for cooling water and use some generic data which is a fairly good approximation, for summing up my cooling water requirements and sizing for a plant/unit having say 100 pumps with various cooling plans depending on the pump type as specified in the pump data sheet?

If cooling water is required for your pumps I would suspect that even in basic data sheets the required information would be present.
http://www.edwardsva...ct_Details.aspx

While the link I indicate is for a vacuum compressor a similar amount of information should be available for pumps. In the technical data you get the cooling water requirements.

Therefore I would suggest that what you are after is manufacturer specific.

However to guesstimate (back of matchbox accuracy) what you could do is to look at the temperature rise across each pump by examing incoming temperatures, efficiency compression ratio etc. You could then work out the required cooling capicity needed (by calculating temperature out with no cooling and cooling needed for acceptable temperature out).

[ankur2061]

If cooling water is required for your pumps I would suspect that even in basic data sheets the required information would be present.

Dear Riven,

None of the preliminary or FED data sheets which I have seen or prepared have this kind of data. The CW requirement data box is always marked with an asterisk or note where the asterisk or note says: 'Vendor to Provide'.

As I understand from what is written in API 610 all the cooling plans are very specific with specific piping routing/layout and have specific CW requirements. Vendors generally provide the data in the filled up data sheet by removing the asterisk marks. The only thing I am trying to do is to circumvent the time period which is required for the vendor/manufacturer to provide this data. Sometimes the vendors take a pretty long time to communicate back to you, and the exigiency of the project demands that you need to have good ballpark numbers with you as a data base for having a CW estimate for the plant/unit. As I mentioned earlier, a ±10% estimate would serve me fine.

So do we have these kind of numbers or shall I say 'I quit' and just wait for the vendor/manufacturer to provide some figures for the specific cooling plan.

Hoping to get some further insight on this. I hope that some 'pump specialist' or 'pump manufacturer' is a regular visitor to the forum or is it wishful thinking on my part?

Regards,
Ankur.

[chemtan]

Dear Ankur,

I also faced this while working on FEED of Utilities section for a client. When consulted, my senior told me use a 10GPM per pump as a "rough" cooling requirement. The vendor came back with his info after 2 weeks and so I was saved from some sleepless nights.

I do not want to "advocate" using this figure, but, it turned out to be a fair estimate as the cooling need for pumps did not exceed this figure in my case.

Just looking at observation from ARAZA that mostly lines are 0.5\0.75 inches, seems like I was not too far away from a good guess.

Again, would say that just sharing my experience, not "advocating" to use this figure.