T-Pieces and Y-Pieces
T-pieces and Y-pieces for branching galvanised spiral duct runs. Whenever one duct has to become two — a second extract point, a new machine drop, a supply branch to another room — one of these three fittings does the job, each available in a full run of diameters to match our spiral ducting.
T-piece or Y-piece?
- 90 degree T-pieces (80mm to 630mm) take the branch off at a right angle — compact and simple, the standard choice for general ventilation.
- 45 degree T-pieces (100mm to 355mm) sweep the branch in at 45 degrees, keeping airflow smoother where the branch carries significant volume.
- 45 degree Y-pieces (100mm to 710mm) split the run symmetrically — the low-resistance option favoured in dust and fume extraction, where sharp junctions cost suction and collect material.
Sizing and fitting branch junctions
As a rule: comfort ventilation tolerates 90 degree tees; extraction systems repay the gentler 45 degree entries, which keep transport velocity up and give dust nowhere to settle. All three fittings share the branch diameter with the main run, so where the branch needs to be smaller, pair the fitting with a reducer on the branch leg — the usual arrangement, since branches rarely carry as much air as the main. And if the duct is already installed, you may not need a tee at all: a saddle or shoe cuts a branch into existing duct without breaking the run. Junctions join, screw and seal like every other spiral component. Stocked sizes despatch next day when ordered by 3pm, with free UK mainland delivery on orders over £400 ex VAT.
