Super Wide™ Kalsi Seals
Why Super Wide Kalsi Seals were developed
Super Wide 739-Series Kalsi Seals were developed for oil-to-mud partitioning (i.e., mud seal) service in drilling fluid swivels and similar equipment that uses lubricant overpressure, where the pressure of the seal lubricant is maintained at a value that is greater than the pressure of the drilling fluid. The dynamic sealing lip is the widest of any rotary seal we offer, providing extra sacrificial material to accommodate axially acting wear mechanisms, such as third-body wear and pressure-related extrusion damage. The narrowest part of the lip is 4.5 times wider than our standard width seals and double the width of our extra wide seals. In addition to providing extra sacrificial material, the additional width also provides significantly more lip strength for resistance to the varying differential pressures and relatively large extrusion gap clearances that are encountered in lubricant overpressure-type partitioning service. The extra lip width of the Super Wide seal is made possible with enhanced lubrication waves, which provide the strong lubricant pumping action that is necessary to lubricate such a wide dynamic sealing interface.
How our laboratory testing was conducted
Our developmental testing was performed with differential pressure as high as 1,500 psi using an ISO 68 viscosity grade lubricant and a radial extrusion gap clearance of 0.020”. Rotary speed ranged from 58 to 144 sfpm, to bracket the operating conditions of oilfield power swivels with 2.75” OD washpipes. The 1,500 psi testing exceeds the typical differential pressure encountered in lubricant overpressure systems by a significant margin.
The lower pressure testing was performed with a test seal that was exposed to a drilling fluid environment. In the 144 sfpm testing, undersleeve coolant circulation was used to limit the bulk lubricant temperature to 162°F. In the 58 sfpm testing, the bulk lubricant temperature averaged 102°F and typically did not exceed 112°F. Seal condition was excellent after hundreds of hours of testing (see images). At 58 sfpm AND 100 psi the hydrodynamic pumping related leakage per wave was 0.25 to 0.30 ml/hr. At 144 sfpm, the leakage per wave was 0.22 ml/hr at 15 psi, 0.45 ml/hr at 62 psi, and 0.67 to 1.08 ml/hr at 200 psi. The number of waves for any seal diameter can be estimated by dividing the seal diameter by 0.3125.
How to purchase Super Wide Kalsi Seals
For a list of the available sizes of our Super Wide rotary seals, see our shaft seal catalog. Additional sizes can be manufactured, if desired. Seal purchase orders and requests for quote should be sent to the attention of Seal Sales via fax at 281-240-0255, or by e-mail. For assistance in implementing Super Wide seals in your equipment, call 281-240-6500 or click here.