CR Seals

What Are CR Seals?

A CR Seal is a ring-shaped part fitted around a rotating shaft, at the point where the shaft enters a bearing housing, gearbox, or pump. Its job is simple but important: keep the lubricating oil or grease inside the machine, and keep dirt, dust, and water from getting in from outside.

The name comes from Chicago Rawhide, the company that first made these seals over a century ago. The brand is now part of SKF, and CR Seals today cover a wide range of designs, lip materials, and sizes, built to suit shafts running at different speeds, pressures, and temperatures. A rubber or PTFE lip inside the seal presses lightly against the shaft, forming the barrier that does this protective job.

CR Seals vs a Basic Rubber Seal: What Is the Difference?

A basic rubber seal from a general hardware supplier may hold back a small amount of oil for light, short-term use, but it is not engineered for continuous rotation, heat build-up, or pressure. CR Seals are designed and tested specifically for rotating shafts, with lip shapes such as the SKF Wave design that reduce friction and heat even during long, non-stop running.

For everyday, low-demand fittings, a standard seal might get by. But for shafts that run for years under load, speed, or harsh conditions, a purpose-built CR Seal keeps oil in and contamination out far more reliably, which means fewer bearing failures down the line.

Types of CR Seals

• Wave-Lip Seals (CRW / CRWH / CRWA Series): Feature a wavy sealing lip that spreads contact pressure evenly around the shaft, cutting friction and heat. A common first choice for motors, pumps, and general gearboxes.
• Heavy-Duty Wave-Lip Seals (HDW Series): Built with a reinforced case and lip for tougher jobs, such as construction, agricultural, and off-highway axles that see shocks and rough conditions.
• Metal Case, Spring-Loaded Seals (CRS Series): A traditional design where a coil spring keeps steady pressure on the sealing lip. Reliable for general industrial shafts running at moderate speed.
• PTFE Lip Seals: Use a PTFE lip - a tough, low-friction, heat-resistant material - for shafts running dry, very fast, very hot, or in contact with mild chemicals.
• SKF Speedi-Sleeve: Not a seal itself, but a thin wear sleeve fitted over a shaft that has worn a groove where the old seal used to run. It gives the new seal a smooth surface to seal against, instead of replacing the whole shaft.

CR Seal Series, Shaft Range & Applications

The table below is a general guide to common CR Seal series, the shaft sizes they typically cover, and where each is used. Share your exact shaft diameter, housing bore, and running condition with our team for a precise match.

Benefits of Using the Right CR Seal

• Keeps Lubricant Where It Belongs: Stops oil or grease from leaking out and running low unnoticed.
• Blocks Dirt and Moisture: Protects bearings and gears from contamination that causes early wear.
• Runs Cooler: Low-friction lip designs, such as the wave lip, cut down heat build-up on the shaft.
• Fits a Wide Range of Shafts: Multiple series and sizes mean most rotating equipment has a matching seal.
• Reduces Downtime: A good seal delays the chain reaction of leak, contamination, and bearing failure.

Where Our Export Customers Use CR Seals

The exact seal design that suits a shaft depends heavily on local machinery, dust levels, and running heat. Here is how demand looks across the countries we export to:

How to Choose the Right CR Seal

• Measure the Shaft and Housing Bore: The seal's inner and outer diameter must match the shaft and housing exactly.
• Check Running Speed and Heat: Fast or hot shafts usually need a low-friction wave-lip or PTFE-lip design.
• Check for Pressure or Contamination: Pressurised housings or dusty sites may need an auxiliary dust lip or a pressure-rated series.
• Inspect the Shaft Surface: A worn or grooved shaft may need a Speedi-Sleeve before the new seal is fitted.

Common Mistakes to Avoid

• Fitting a Seal on a Damaged Shaft Surface: A scored or worn shaft will wear out even a new seal quickly.
• Wrong Lip Material for the Job: A standard rubber lip will not last long in high heat or chemical exposure.
• Forcing the Seal In at an Angle: This can fold or cut the lip before the machine even starts running.
• Skipping Lubrication on the Lip Before Fitting: A dry lip can be damaged the moment the shaft starts turning.

Simple Maintenance Tips for Longer Seal Life

Check regularly for oil stains or drips near the shaft, since this is usually the first visible sign a seal is wearing out. Keep the shaft area clean and free of built-up dirt, as trapped grit can wear down the sealing lip faster than normal running. Replace a seal whenever a shaft or bearing is opened up for service, rather than reusing an old seal that has already been compressed and worn by the shaft.

Need reliable CR Seals for your rotating equipment? Get a fast export quote from Shree Balaji Export - trusted delivery to Sri Lanka, South Africa, UAE, Nigeria, Egypt, Indonesia, Thailand, Kuwait, and worldwide.