Wrc 107 Nozzle Loads???

[stanier]

Can someone please explain the relevance of this document to nozzle loading?

 

[prex]

The object of the document are nozzle loadings on vessels and pipes. A companion of WRC107 is WRC297: look in the site below, under vessels -> WRC297, to see a calculation sheet. prex
motori@xcalcsREMOVE.com

http://www.xcalcs.com

Online tools for structural design

 

[arto]

If you want a quickie way to calculate Nozzle Loads on shells, try Bednar's or Stikvoort's methods.

[H.H. Bednar, "Pressure Vessel Design Handbook," 2nd ed.(New York: Van Nostrand Reinhold),1986. {after Roark, this is the best book ever written }

[W.J.Stikvoort, "Pressure-Vessel Design, Nozzle Piping Reactions," in "Encyclodedia of Chemical Processing & Design" vol. 42 pp237-44 (New York: Marcel Dekker) 1993.
also articles in Chemical Engrg. mag 7/7/86 & June 94 ]

 

[v2jay]

WRC-107 calculates stresses on the nozzles with the imposed load from the piping connected to the nozzles. WRC-107 compares stresses with the allowable stresses as per ASME Section VIII Div - I. The imposed loading from piping on the nozzle element is used to calculate the amount of stresses applied on the welding joint between pipe and vessel. Nozzle failure can be determined through WRC-107 procedures.

 

[hafiz]

Does the allowable loads calculated as per the WRC 107 and 297 take into consideration any reinforcement load requirement, such as for reinforcement pad around the nozzle?

 

[prex]

No, hafiz: you need first to check opening reinforcement to pressure per code rules, and only after that you can check the nozzle against external loads. In the latter calculation, if there is a repad, you can take the total wall+repad thickness as the wall thickness, but you need to add a check at repad outside diameter. prex
motori@xcalcsREMOVE.com

http://www.xcalcs.com

Online tools for structural design

 

[hockchong]

Hi Prex,
Currently I am using Finglow for my vessel calculation. I have a project in hand where the OD of the vessel is 30" and have a 24" nozzle. Both are using 6.35mm plate (Super duplex). When I perform WRC107 on the nozzle, the stress fail on the nozzle itself (and not the shell). If I am not mistaken, other software like PVElite didn't check on the nozzle neck stress. Can I ignore the stress check on the nozzle neck?

Thanks.

 

[LSThill]

Hi hockchong (Mechanical)

WRC-107 Engineering Tool's for Piping and Pressure Vessel Analysis:

CODEWARE COMPRESS software: FE-NOZZLE DOSE check on the nozzle neck stress.

Paulin Research Group software: FE/Pipe, the industry's leader for piping and vessel FEA stress analysis and design, NozzlePRO for nozzle and structural supports DOSE check on the nozzle neck stress.


Leonard@thill.biz

http://www.thill.biz

 

[aybee]

WRC 107 as written originally was for attachments to spherical shells with no opening . It also does not address internal pressure only external loading so it needs to be approached with caution I believe Codecalc incorporates the other stresses due to pressure with the WRC 107 stresses

 

[hockchong]

Thanks guys. BTW, according ASME Div. 2, membrane + Bending stress of the nozzle shall considered as primary load (that's mean the allowable stress is 1.5Sa). Is there any situation it can be considered as secondary load, so that I can use 3Sa as allowable load?

 

[prex]

hockchong,
what you state holds with the bending stress in the nozzle calculated over the full circular section, just as in a pipe. Local bending of the nozzle wall seen as a shell is secondary.

prex

http://www.xcalcs.com

Online tools for structural design