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Ronstan Ball Bearing Orbit Blocks, Series 55 - Upright Lead

Ronstan

Don't Pay $78.60
Our Price $72.70
(You save $5.90 )
SKU:
RON-RF55171
(No reviews yet) Write a Review

Features:

  • Lightweight
  • Highest working load in its class
  • Secure, versatile attachment
  • Low profile and compact
  • Ultra low profile thru-sheave becket
  • Low friction 2-stage ball bearing system provides consistent performance over the full working load range.
  • SP versions feature a Nylatron® sheave suitable for both rope and wire

Applications:

  • Mainsheet systems on dinghies, sportsboats and small keelboats to 9m (30ft)
  • Halyard, Vang and Backstay application on boats to 8m (26ft)
  • Control line applications on larger yachts

Materials:

  • Ball bearings - High compression strength carbon black Acetal
  • Stage 2 bearing - Carbon fibre reinforced, PTFE impregnated Nylon
  • Frame/Cheeks - Toughened, glass fibre reinforced Nylon
  • Rope Link: UV stabilised, multi-strand impregmented SK75 Dyneema®
  • Sheave: Carbon fibre reinforced, PTFE impregnated Nylon
  • Ball Bearings: High compresssion strength carbon black Acetal
  • Stage 2 Bearing: Carbon fibre reinforced, PTFE impregnated Nylon

Lightweight

Kilogram for kilogram of working load, BB and RT Orbit Blocks™ are the world’s lightest. The unique orbital design allows the bearing to only be in the active areas of the floating sheave. This minimises the mass of the inactive return race and hub.

Weight and bulk are further reduced in the different block configurations. The ball bearing single and becket block has a through-sheave becket arrangement. The result? The lowest weight possible.

Multi-sheave blocks have only single intermediate cheeks and an ultra-light and efficient head arrangement. This gives a 30% weight saving advantage over the nearest competitor. Other brands just link together their single blocks. This results in unnecessary double cheeks between each sheave, held together by a heavy steel channel across the top of the block. 

Highest working load in its class

The orbital ball-bearing arrangement gives the largest possible bearing race diameter. This maximises load performance. The proven Ronstan 2-stage bearing system features high compression grade acetal ball bearings and a secondary full-contact bearing. This gives minimum friction across the full working load range.

The floating sheave and bearing system is supported by a fibre-reinforced load frame. The design was computer modelled to be stress optimised. The Dyneema® Link is produced from FSE Robline SK75 fibre, which is 10 times stronger and lighter than steel, and provides the final connection from the block to the load point

Part Number Sheave Ø Max. Rope Ø Max. Cable Ø Pin Ø M.W.L. B. L. Weight
RON-RF55171 55mm 10mm - - 500kg 1000kg 91g

Ronstan Ball Bearing Orbit Blocks, Series 55 - Upright Lead

Ronstan

Don't Pay $78.60
Our Price $72.70
(You save $5.90 )
SKU:
RON-RF55171
(No reviews yet) Write a Review
UPC:
9316800373499
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