Tips October - December 1999

Preferred Points of Attachment to Pipe

This tip will give you a guideline for selecting areas that are the preferred attachment points.

  • On a pipe rather than on piping components such as valves, fittings, or expansion joints. Under highly localized loading, flanged or threaded joints may leak and valve bodies may distort with resulting seat leakage or binding. Attachments to heavy components, however, may be acceptable and even desirable where the effect can be properly provided for.
  • On straight runs rather than on sharp radius bends or welding elbows, since these are already subjected to highly localized stresses on which the local effects of the attachment would be superimposed. Furthermore, attachments on curved pipe which extend well along the length or circumference of the bend will seriously alter the flexibility of the component.
  • On pipe runs which do not require frequent removals for cleaning and maintenance work.
  • As close as practical to heavy load concentrations such as vertical runs, branch lines, motor operated or otherwise heavy valves, and minor vessels such as separators, strainers, etc.

Preferred Attachment to "Structure"

This tip will give you a guideline for dealing with structures when connected with piping.

  • Apply loads to columns and beams near main-member intersections to minimize bending effects.
  • Avoid the introduction of unnecessary torsion or lateral bending effects.
  • Avoid the introduction of movements or transverse loading to slender members (such as wind bracing) and particularly to compression members where instability controls the design.
  • Confine connections to an independent structure or a foundation when dealing with piping subject to pulsating flow or transmitted mechanical vibration, unless a careful and comprehensive analysis assures that the structures, buildings, etc., are of adequate strength with nonresonant frequency and sufficient stiffness to control amplitude within the bounds required by general comfort level of personnel.
  • Provide anchors and extremely flexible and nonresonant intervening pipe runs (e.g., expansion joints) to machinery that introduces mechanical vibrations, in order to isolate the effect by reducing transmissibility.

The above tips are excerpted from SST 101: Piping Design and Analysis Seminar Notes.

Printing Rendered Images in CAEPIPE

Update (Feb 1, 2000): As of v5.02E, CAEPIPE has built-in capability to print rendered images on to the printer. After rendering the image in the graphics window, click on the menu File > Print...

Presently, CAEPIPE does not allow any (printing) operation on a rendered image. Sometime in the near future, it is proposed to add the ability to print the rendered image to a printer, and write to a file. Until such time, the following workaround can be satisfactorily used for printing.

Step 1: Adjust the graphics window and the image (including all settings such as node numbers, symbols, etc.) to the size and the settings desired.
(Change to a white background if you want to save the ink in your printer toner).

Step 2: With the image displayed correctly (with focus in this window), press the Alt+Print Screen key on your keyboard. This action will copy the window as a screenshot to the clipboard.

Step 3: Open a paint program (such as MS-Paint, under Start menu>Programs>Accessories>Paint).

Step 4: Press Ctrl V (or select Edit menu>Paste) to paste the just captured image into the paint program.

Step 5: Use the "Select" tool (dotted rectangle) and mark the area around the rendered image using the mouse (exclude borders if not required).
Click on Edit menu>Copy, to copy the marked image onto the clipboard.

Step 6: Open a New document (click on File menu>New...), close the previous "untitled" document that contains the whole screenshot (without saving), when prompted.

Step 7: In the new document, press Ctrl V (or click on Edit menu>Paste) to paste the rendered image.

Step 8: Add your notations, if desired.

The file (image) is ready to print on your (color) printer.