Things That Cannot Go Wrong!

PVE-6322, Last Updated: July 29 2013 By: Laurence Brundrett

Solid Model Sketch of Flanged and Dished Vessel Head

A Flanged and Dished Head

The sketch that creates this flanged and dished pressure vessel head has 6 dimensions that need to be updated before it can be used:

  • OD – outside diameter (85.750″)
  • tNom – Nominal Thickness(0.750″)
  • tMin – Minimum thickness after forming (0.625″)
  • SF – Straight Flange(2.000″)
  • ICR – Inside Crown Radius(85.750″)
  • IKR – Inside Knuckle Radius(8.000″)

These dimensions are taken from the calculation set which is run first. Normally, the user has to set these dimensions three times: first in the calculation set; second in the parts sketch and: third for the part description that shows up in the Bill of Material. These three sets of dimensions must be kept in sync no matter how many times the design is revised!

Solid Model Sketch with Dimensions

The required dimensions to create a Flanged and Dished Head

This part from our library builds it’s own description. The custom properties for the part has an entry for “Description” that contains a long formula:

Head, F&D – “OD@Sk1@F&D Head.SLDPRT” OD, “tNom@sk1@F&D Head.SLDPRT” Nom., “tMAF@Sk1@F&D Head.SLDPRT” MAF, “SF@Sk1@F&D Head.SLDPRT” SF, “ICR@Sk1@F&D Head.SLDPRT” ICR, “IKR@Sk1@F&D Head.SLDPRT” IKR

F&D Head.SLDPRT is the files name. SolidWorks reads the dimensions from the model and populates the description:

Head, F&D – 85.75 OD, .750 Nom., .625 MAF, 2.000 SF, 85.750 ICR, 8,000 IKR

This complete purchasing description always matches the dimensions in the model no matter how many times it is updated! A source of errors has been eliminated and the amount of work reduced. If only there was some way of automatically linking the model dimensions to the calculation set…