PVC Pipe and Fittings Library

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Revision as of 17:33, 25 March 2018 by Ruslan (talk | contribs) (→‎Corners)
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Basics

This is a library of all the current PVC Pipe and Fittings that have been made in freecad for OSE. Many fittings can be created using #OSE Piping Workbench.

Pipes

The dimensions of the PVC pipes can be found here PVC_Pipe. Wikipedia on Nominal Pipe Size (NPS) [6],

A pipe is described by its outer diameter OD, its wall thickness Thk and its height[1] H.

Pipe-dimensions.png

Workbench

To create a pipe, click CreatePipe.svg in OSE piping workbench. Adjust CSV pipe.csv in tables directory within workbench directory to add new pipe dimensions to the list.

Create-pipe-screenshot.png
Create-pipe-cad-screenshot.png

Notations used by others

  • O.D. - outer diameter.
  • Average I.D. - average inner diameter (why average?). This dimension determines the size of the pipe.
  • Min. Wall - thickness of the pipe wall.
  • Schedule - determines (indirectly) the thickness of the wall.

Elbows

Useful links: [7]

Elbows

An elbow is described by an angle alpha, outer pipe diameter POD, inner pipe diameter PID, H, J, M.

Elbow-dimensions.png

Workbench

To create an elbow, click CreateElbow.svg in OSE piping workbench. To add new elbows, adjust elbow.csv in tables directory within workbench directory.

Create-elbow-screenshot.png
Create-elbow-cad-screenshot.png

Couplings

A (general) coupling is described by dimensions: POD, POD1, PID, PID1, L, M, M1, N. The dimensions POD1 and PID1 are not from a official specifications. They are derived from pipe size and schedule. In a reducer coupling, the pipe dimensions on one side POD and PID differ from on the other side POD1 and PID1.

Coupling-dimensions.png

Workbench

To create a coupling, click CreateCoupling.svg in OSE piping workbench. To add a new coupling to the part list, adjust coupling.csv in tables directory within workbench directory.

Create-coupling-screenshot.png
Create-coupling-cad-screenshot.png

Bushings

Important: There was a bug in workbench with version until 03. March 2018, where PID was used instead of POD.

A bushing is described by dimensions N, L and pipe dimensions. As pipe dimensions we use POD, PID1, and POD1.

Bushing-dimensions.png

Workbench

Important: There was a bug in workbench with version until 03. March 2018, where PID was used instead of POD.

To create a bushing, click CreateBushing.svg in OSE piping workbench. To add a new coupling to the part list, adjust bushing.csv in tables directory within workbench directory.

Create-bushing-screenshot.png
Create-bushing-cad-screenshot.png

Tees

Almost General Tees

A tee is described by parameters G, G1, G2, H, H1, H2, M, M1, and pipe dimensions. As pipe dimensions we use POD, POD1, PID, and PID1.

Tee-dimensions.png


Workbench

To create a tee click CreateTee.svg in OSE piping workbench. To add a new tee to the part list, adjust tee.csv in tables directory within workbench directory.

Create-tee-screenshot.png
Create-tee-cad-screenshot.png

Cross

Almost General Cross

A cross is described by dimensions G, G1, G2, G3, H, H1, H2, H3, M, M1, and pipe dimensions. As pipe dimensions we use POD, POD1, PID, and PID1.

Cross-dimensions.png

Workbench

To create a tee click CreateCross.svg in OSE piping workbench. To add a new cross to the part list, adjust cross.csv in tables directory within workbench directory.

Create-cross-screenshot.png
Create-cross-cad-screenshot.png

Corners

An corner is described by dimensions G, H, M and pipe dimensions. As pipe dimensions we use POD and PID. Outer-corner-dimensions.png

Workbench

To create a corner, click CreateCorner.svg in OSE piping workbench. To add a new corner to the part list, adjust corner.csv in tables directory within workbench directory.

Create-corner-screenshot.png
Create-corner-cad-screenshot.png

Genaerated Library Parts

Library of STEP Downloads from McMaster Carr

Comparable in size to generated parts - except for some parts which are way too heavy.


OSE Piping Workbench

OsePipingWorkbenchIcon.svg


Implemented are:

  • pipe
  • coupling
  • bushing
  • elbow
  • tee
  • cross
  • outer corner

OsePiningWorkbenchScreenshot.png

Installation

In a Linux system

$ mkdir ~/.FreeCAD/Mod
$ cd ~/.FreeCAD/Mod
$ git clone https://github.com/rkrenzler/ose-piping-workbench.git

Check.png Command line instructions work on Ubuntu 16.04

Hint:For those new to Linux, always remember Linux is case sensitive. mkdir ~/.FreeCAD/Mod creates the mod directory inside of FreeCAD. this might already exist, and that is fine.

Remarks about the coupling code

To create a simple coupling or a reduced we internally use a more general coupling. This general coupling is described by 9 dimensions: POD, PID, POD1, PID1, X1, X2, N, M, M1. The dimensions POD, PID, POD1, and PID1 are derived from the pipe sizes. The are abbreviations of Pipe Outer Diameter and Pipe Inner Diameter. The dimensions X1 and X2 are not official dimension names.


Coupling-calculations.png

The offset a1 is calculated in such a way, that the thinest part of the middle section is not thinner than the walls on of the both sockets. Lengths a2, a3, a4 and angle b1 are derived from the dimensions and are only used to calculate a1.



FAQ

  • Do we really want to 3D-print pipe fittings? Somehow I have doubt about mechanical properties of the 3D-printed products.
    Yes. For high pressure applications - 300 PSI - we would have to be very careful. For low pressure, such as 5 PSI, it's not a problem. Eventually, we want to refine printing techniques where our fittings can do what standard schedule 80 ABS fittings can do.
    • Also with things such as part baking/anealing, composite filaments, and SLA or SLS Printers, very durable parts can be made



See Also



Useful Links

  1. We use height instead of length in order to make a pipe similar to a FreeCAD cylinder. These particular choice of pipe dimensions make it more compatible with pipes from flamingo workbench.