Dear Members, I’m checking suction and discharge nozzles loads in a vertically suspended pump (not vertical IN LINE), I’m using API 610 to evaluated nozzle loads because the manufacturer of the pump didn’t give me the allowable loads.

The center line of my discharge is in “x” axis direction, the shaft (driver) center line is in “y” axis direction and my suction is in “y” axis, like a wet pit, but in our case we have like a caising in concrete where we provide the fluid to the pump’s suctions in the bottom of the pump.

My problem is that I don’t know what “centerline cosines” use in this case because the help that bring the software is just to vertical in line and horizontal pumps.

I really appreciate if somebody could help me.

Regards,

Gustavo Cuervo
Project - Mechanical Engineer
Facilities and Services
Tel - Fax: (57) - (1) - 628-8322

In your case ( I think according to API classification it is VS3) your suction nozzle is not having any piping load as it is not connected to piping.So the only load that you need to take care of is the discharge nozzle load.

API 610 is very explicit about the loadings on vertical in line pumps and horizontal pumps, but the only ref. that we find about allowable loadings on Verically suspended pumps is paragraph 2.4.1.which states " vertically suspended pumps shall be designed for satisfactory performance when subjected to the forces and moments in table 2A ".There is no additional allowance as given in Apendix F for pumps of this category like the way it is recommended for Horizontal and Vertical in line pumps.

I think because of this lack of information ( I will be very happy if somebody can refer any part of API 610 where the allowable loads for verically suspended pumps are otherwise mentioned), Caesar II uses the direction cosine concept only for Horizontal and Vertical in line pumps.

In your case it will be best for you to compute the CAESAR II output load at discharge nozzle and check it against the " side nozzle" allowable as per table 2A against the nozzle size.

Or else you define it as a " vertical in-line pump", give the direction cosine for the discharge nozzle as the "direction cosine " in CAESAR II and check for the results. Needless to say that since the suction is not connected to piping, suction load is zero.

Hope this answers your question.

Anindya Bhattacharya