A new chapter titled “Using Kalsi Seals in side port swivels” has been added in the Application Engineering section of our rotary seal handbook. This new, well-illustrated chapter describes the best practices for designing high pressure side port swivels for use with Kalsi-brand rotary shaft seals.
The suggested swivel design incorporates Kalsi Engineering’s patent pending floating backup rings. These rings provide the smallest practicable extrusion gap for the pressure-retaining seals, which enhances pressure capacity and promotes long sealing life. The design is a modular arrangement that utilizes simple stacked housings to locate the seals, backup rings, and bearings. The housings are bolted to a central housing that incorporates the side port. This arrangement is robust, economical to manufacture, and simple to assemble and disassemble. It completely avoids the use of radial O-rings, which are difficult to assemble in large diameters, and can fail in extreme high pressure service. The design minimizes the number of precision machined surfaces, and locates the few that remain in positions that are easily accessible during machining and inspection. It also totally eliminates the use of custom threads.
Although the new chapter focuses on high pressure side port swivels, the basic stacking housing arrangement is also adaptable to other equipment, such as hydraulic swivels, top drive washpipe assemblies, and rotary control devices (RCDs). The chapters that focus on such equipment will be revised to provide detailed design information as time permits.