4″ CBN/ST UNION Left
Type S.T. – Double Flow (Stationary Center Tube)
Fitted with an adapter suitable for double flow with a stationary center tube. This gives flow areas through the center tube and annulus. The center tube – provided only if ordered – is fixed to the union end by means of a screw thread (dimension “O”). Flow can pass in through the center tube and return through the annulus or be reversed. For steam applications, the center tube is curved to reach the condensate in the bottom of the cylinder. If the roll neck diameter to length ratio prevents the use of a curved tube, a syphon elbow can be specified instead. See the Accessory Section or contact us for more information about the options available.
The rotary C.B.N. union is a self-contained, self-supporting rotary seal for the leak-proof transfer of fluids such as steam, water, air and oil to and from rotating machine shafts. The type of rotary seal fitted to this model is a Filton® Bellows Seal containing a flexible stainless steel bellows which is self-adjusting, eliminating the maintenance common with conventional packed glands. Rotary sealing is created by relative rotation between extremely flat sealing faces held in contact by the spring characteristics of the bellows combined with an additional sealing force created by the pressure of the fluid passing through the rotary union. The bearings fitted to the union are separate carbon thrust and journal bearings in which a hard chromed and ground spindle rotates.