Nozzles & Equipment
Siamese
A siamese is an appliance that combines two or more incoming lines into a single outgoing line — the mirror image of a wye. It is used to feed one demanding line or system from multiple supply hoses.
Where a wye divides, a siamese merges. Combining two supply lines into one reduces the friction loss the supply sees, which is useful when a single large line cannot deliver the needed flow over distance.
A fire department connection on a standpipe or sprinkler system is essentially a siamese inlet, letting the engine pump into the building through more than one hose at once.