VIEGA Smartpress Wall Plate 16 x 1/2″, Gunmetal, Press x Internal Thread, Art. 729479

A female thread runs round the inside of an opening, while a male thread sits on the outside of a part. This wall-plate elbow has an Rp1/2 female outlet, so it receives a tap, valve or connector with a 1/2" male thread. The 16 mm multilayer pipe is not threaded at all: it is pressed into the other end.

The outlet is an Rp1/2 thread, a parallel female pipe thread meant to take a tapered R male thread, so the joint becomes tight in the thread turns rather than on a flat gasket, as is usual with G threads. For that seal Viega names hemp combined with thread-sealing paste, or a sealing tape certified for drinking water.

Viega specifies Smartpress press jaws for plastic piping systems, model 2799.7 or 2784.7, on a press machine with constant pressing force; for 16–25 mm the hand press tool 2782.5 may be used instead. With Pexfit Fosta pipe, first remove the outer coating and aluminium layer over the press-sleeve length using Viega chamfer 2758.5. Push the 16 mm pipe into the press end until it appears in the inspection window, then press.