Figure 4  Common 04 Tee Fittings

Tee fittings are a special case where the flow rate through the tee will be different in each branch, therefore two fittings must be used (one on each branch) to model the separate losses in each branch. 


The correct flow rates along each path will be applied to the appropriate 'Through Tee' or 'Branch Tee' fitting coefficients when calculating the fitting pressure losses.


Note: In this example, pipe entrance (from tank) fittings have been purposely omitted for clarity, in order to focus on the tee fittings.


Case A: Diverting Tee (one branch line).

'Through Tee' fitting added to through pipe leaving the tee joint. 

'Branch Tee' fitting added to the branch pipe leaving the tee joint.


Case B: Converging Tee (two branch lines meet)

'Branch Tee' fitting added to both pipes feeding the tee joint.


Case C: Diverting Tee (two branch lines)

'Branch Tee' fitting added to both pipes leaving the tee joint.


Case D: Converging Tee (one branch line entering)

'Through Tee' fitting added to pipe feeding the tee joint.

'Branch Tee' fitting added to branch pipe feeding the tee joint.


UN-EQUAL PIPE SIZES:

Where the pipes sizes that connect to the tee are not equal, the fitting sizes used should match the nominal pipe sizes.