Accessories - Steam Syphons

Duff-Norton Stationary and Rotating Syphons Features: Minimizes syphon breakage Reduces syphon fatigue problems Reduces expensive downtime Simple to install Needs little maintenance Improves heating efficiency of paper machine dryer cans by reducing syphon clearance Designed for use with Duff-Norton rotating joints Custom-assembled to fit your operation The system consists of a stationary syphon pipe, syphon support tube with steam ports, special coupling with hinged joint and a syphon pipe extension. The syphon pipe is supported at two points — at one end by the joint, and inside the can by a hardened 440 stainless steel journal within a rotating bronze bushing

mounted inside the protective syphon support tube. The bearing requires no periodic maintenance. The rigid, protected mounting arrangement stops syphon pipe flexing and ultimate fracture, common to conventional systems with only single-point mounting. The Syphon Support System pays for itself rapidly by reducing expensive maintenance and unscheduled downtime. The entire System can be installed or removed from outside the can. It is not necessary to remove the manhole cover or enter the can for installation or maintenance inspections. The extended support permits reduced syphon clearance to assure optimum removal of condensate and thus improve heat capacity. Each support system is manufactured and custom-assembled to fit the exact dimensions of the user’s dryer can. Critical dimensions must be supplied when ordering (see drawing on the next page.). Developed primarily for use with Duff-Norton joints, the Duff-Norton Syphon Support System may be adapted to other makes of dual-flow, Type “S” and rotating sealing joints.

Non-Rotating Syphons The system shown on this page is a stationary type using a hinged syphon elbow as shown on the next page. For less severe cases, such as small diameter slow moving short journal cans, only the syphon elbow used as shown on page 86 may be required. For moderately severe service, with longer journals and surface speeds up to approximately 400 rpm the support system becomes desirable, still using the syphon elbow, as shown below. For severe conditions with speeds above 400 rpm a “tri-axially” threaded support system is recommended. This connection is much stronger than the syphon elbow and allows no “jostling” by cascading condensate.

Reduce This Common Cause of Syphon Breakage With the Duff-Norton Syphon Support System Syphon pipe in conventional dual-flow rotating joint system is (1) supported at only one point, and is free to flex inside the dryer can. The long, overhung pipe is (2) impinged by cascading water and (3) buffeted by the water at the pickup tip. This results in a fatigue fracture at the threaded end fastened in the joint.