Distribution headers are where stainless press shows up a lot: hot and cold water headers in plant rooms, compressed air drops, process lines feeding several machines. The Standard Press 316 stainless range gives you two ways to build one: the 5-outlet manifold, or a row of female BSP branch tees joined with short lengths of tube.
What the manifold is
A single 316L body with press sockets on each end of the run and five male BSP outlets. It comes in 28, 35, 42 and 54mm runs, each with 1/2" or 3/4" outlets. The listing describes it for hot and cold water, compressed air and process headers, replacing five separate tees and the joints between them.
The cost comparison
| Run x outlets | Manifold | 5 x female BSP branch tee | Difference |
|---|---|---|---|
| 28mm x 1/2" | $169.47 | 5 x $31.81 = $159.05 | Tees $10.42 cheaper |
| 28mm x 3/4" | $180.27 | 5 x $37.93 = $189.65 | Manifold $9.38 cheaper |
| 35mm x 1/2" | $184.73 | 5 x $39.16 = $195.80 | Manifold $11.07 cheaper |
| 35mm x 3/4" | $186.45 | 5 x $41.75 = $208.75 | Manifold $22.30 cheaper |
| 42mm x 1/2" | $199.25 | 5 x $46.15 = $230.75 | Manifold $31.50 cheaper |
| 42mm x 3/4" | $201.61 | 5 x $47.21 = $236.05 | Manifold $34.44 cheaper |
| 54mm x 1/2" | $223.17 | 5 x $60.28 = $301.40 | Manifold $78.23 cheaper |
| 54mm x 3/4" | $233.88 | 5 x $58.83 = $294.15 | Manifold $60.27 cheaper |
Prices inc GST at time of writing, fittings only. The tee column doesn't include the four tube spacers between tees.
The joint count matters more than the price
A manifold has two press joints: one at each end of the run. Five tees in a row have ten: two on every tee. That's eight extra presses, four tube spacers to cut and deburr, and eight more places for a leak. On a 28mm x 1/2" header where the tees are $10.42 cheaper on parts, the labour for eight extra joints wipes that out.
When tees still make sense
- You need custom spacing. The manifold's outlet spacing is fixed. If the outlets have to land on particular equipment or sit wide enough for valves and handles to clear each other, tees let you set the centres.
- You need female outlets. The manifold's outlets are male BSP. Branch tees give female outlets; male BSP branch tees exist in a narrower size list.
- You need more or fewer than five outlets, or outlets in different sizes.
- Your run is outside 28 to 54mm. Female branch tees run from 15mm up to 108mm runs, with outlets to 2" on the larger sizes.
You can mix the two: a manifold for a block of five, then a tee for a sixth.
Finishing a header
- Isolate each outlet so one branch can be worked on without shutting the header down. A threaded ball valve screws straight onto a male outlet. See press vs threaded ball valves.
- Cap the end with a press end cap if the header may be extended later, or plan the run to finish at a tee for a future branch.
- Support it properly. A header with five valves on it is heavy. See supports for stainless press.
- Air lines: check the seal suits the air quality. Oil-carrying compressed air can attack the standard EPDM seal. See stainless press seals.
Frequently Asked Questions
What sizes does the stainless press manifold come in?
28, 35, 42 and 54mm runs, each with five 1/2" or five 3/4" male BSP outlets.
Is a manifold cheaper than five tees?
At every size except 28mm x 1/2", where five female branch tees are $10.42 cheaper. At 54mm x 1/2" the manifold saves $78.23. It also saves eight press joints in every case.
Are the manifold outlets male or female?
Male BSP. For female outlets, use female BSP branch tees.
Can I use the stainless manifold for compressed air?
The listing names compressed air as a use. Check the seal choice with PSA, because oil-carrying air can attack the standard EPDM seal.