Ronstan, Series 55 Orbit Block™, Fiddle with Becket and Link Head, RF55511

Kuvaus

The Ronstan Series 55 Orbit Block™ is renowned for its lightweight design, offering the lightest blocks in its class for the working load. The unique orbital design ensures that the bearing is only present in active areas of the floating sheave, minimizing the mass of inactive components. This block features a through-sheave becket arrangement, resulting in the lowest possible weight. Multi-sheave blocks incorporate single intermediate cheeks and an ultra-light head arrangement, providing a 30% weight saving over competitors.

The block offers the highest working load in its class, thanks to the orbital ball-bearing system that maximizes load performance. The Ronstan 2-stage bearing system includes high compression grade acetal ball bearings and a secondary full-contact bearing, ensuring minimal friction across the working load range. The floating sheave and bearing system are supported by a fiber-reinforced load frame, stress-optimized through computer modeling. The Dyneema® Link, made from FSE Robline SK75 fiber, is 10 times stronger and lighter than steel, providing a secure connection from the block.

Applications include mainsheet systems on dinghies, sportsboats, and small keelboats up to 9m, as well as halyard, vang, and backstay applications on boats up to 8m. It is also suitable for control line applications on larger yachts.

Specifications

• B.L. (kg): 1000
• M.W.L. (kg): 500
• Max. Rope diameter (mm): 10
• Sheave diameter (mm): 55
• Type of Block: Fiddle
• Weight (g): 97

Notes: Small fiddle block sheave has a high load full contact bearing (i.e. not ball bearing). Main sheave has 2-stage, ball bearing. Replacement Link: RF9004-08. Replacement Retainer Clip: RF5001