Allowable external forces on Wellhead christmas tree equipment.

Hi,
We are working for an onshore oil extraction project, including a number of well head christmas trees and associated piping. The question is as follows:
What are the allowable external forces (due to connected piping) on the flowing wing valve of the well head christmas tree equipment.

We looked in to API 6A, but it clearly states that "The effects of external loads (i.e. bending moments, tensions, etc.) on the assembly of components are not within the scope of this document". API 6AF (Technical report on the capabilities of API flanges under combinations of load) and API 6AF1( Technical report on temperature derating on API flanges under combinations of loading) talk about load capacity of API flanges in relation with the bore pressure. (No mention of external loading.)

Anybody who has faced a similar problem? What values are used for allowable loads? Is there any other standard / code that covers this topic?

Have a nice day.
-Mandar.
This message comes from Mandar's desk. Received on Tue Jul 20 02:55:00 2004