djfkaos123
Petroleum
- Jan 17, 2025
- 4
Dear colleagues,
I would appreciate your insight on the following questions related to allowable nozzle loads on centrifugal pumps, particularly in the context of API 610 and HI 9.6.2 standards:
Any practical experience, clarification, or best practices would be greatly appreciated.
Thank you in advance.
I would appreciate your insight on the following questions related to allowable nozzle loads on centrifugal pumps, particularly in the context of API 610 and HI 9.6.2 standards:
- Why are the allowable nozzle loads specified in API 610 typically lower than those in HI 9.6.2 (especially under similar flange sizes and conditions)?
For example, for a 6" end suction nozzle, the API 610 Table 5 values are significantly more conservative than those shown in HI 9.6.2 Equation Set 1. What is the rationale behind API’s more restrictive approach?
e.g. )
API 610 Table 5 : 6" End nozzle Fx, Fy,Fz = 700, 560, 460 lbf ( x 2 = 1400, 1120, 920)
HI 9.6.2 Set1 table : 6" Suction nozzle Fx, Fy,Fz = 2700, 1350, 1500 lbf - If a pump vendor provides allowable nozzle loads that are even lower than both API and HI standard values, how should this be interpreted? Is it a limitation of the specific pump design, or are vendors applying conservative margins? How should we respond in terms of stress analysis and equipment design review?
- Why do many pump vendors only provide allowable loads based on individual forces/moments (single load conditions), and not for combined load scenarios?
Since HI 9.6.2 provides methods for evaluating combined loads (Equation Sets 2–5), is there a reason vendors avoid referencing these in their drawings or documentation?
Any practical experience, clarification, or best practices would be greatly appreciated.
Thank you in advance.
