Chesterton 51K Mill Rotary Seal

Chesterton 51K Mill Rotary Seals
Split Radial Seals for Bearing and Gearbox Protection


​​​​Availability: North America, Europe, Middle East, Africa

Chesterton 51K seals are high-performance radial seals for heavy duty, dynamic rotary seal applications. These seals provide long-lasting sealing and superior protection against ingress of solid particles, dust and fluids. They protect bearing houses and gearboxes across the heavy indiustries—even in the most hostile working environments.​

High-performance elastomers used in these seals create resistance to compression setting, wear, and aging. A broad range of engineered elastomers allow use in high and low ​temperature conditions and provide excellent fluid compatibility. 

The 51K is manufactured by compression molding technology that provides accurate dimensional, geometrical tolerances and improved fitting. The seal body is equipped with a strong, flexible fabric back for tight fitting within the seal cavity. A helical garter spring maintains the seal lip contact and sealing force on the shaft.

According to industrial standards sizing, the 51K is a direct retrofit, which eliminates the need of equipment modification. The 51K is offered in different designs based on application requirements.

Typical Applications: Gear drives, back-up rolls in hot and cold mills, work rolls in hot and cold mills, pulp and paper industry, pumps, propeller shafts, wind turbine main bearings, rotary applications in cement plants

Long-lasting sealing and superior protection against ingress of foreign materials
High-performance elastomers ensure plant-wide usage and long service life
Unique lip design combined with auto-lubricated elstomer offer low friction
Direct retrofit eliminates equipment modification
Split versions are available for easy assembly​
Elastomers NBR80+PTFE FKM70+PTFE
OD FabricTextile + NBR Textile + FKM
Materials of garter springAISI 302-316 AISI 302-316
Lubricating greases -20°C to 100°C (-4°F to 212°F)
-20°C to 200°C (-4°F to 392°F)
Mineral oils-20°C to 100°C (-4°F to 212°F)
-20°C to 200°C (-4°F to 392°F)
​Water 5°C to 100°C (41°F to 212°F)
5°C to 100°C (41°F to 212°F)
Surface speed m/s (ft/min) 15 (2952 ft/min)
25 (4921 ft/min)
Technical pressure MPa (psi) 51K, 51KW, 51KL Solid0.05 (7.25)0.05 (7.25)
Technical pressure MPa (psi) 51K, 51KW, 51KL SplitNo pressure can be appliedNo pressure can be applied
Technical pressure MPa (psi) 51HP Solid0.4 (58)0.4 (58)
Size Range mm (inch)** Seal OD300 to 1200 (12 to 47)300 to 1200 (12 to 47)



Product Datasheet: 51K (English) Datasheet: 51K (English)pdf



Chesterton Polymer Seals Catalog Polymer Seals Catalogpdf