Page 6 - Harken

Harken Materials & Properties

Aluminum
6061-T6: an aluminum alloy that has excellent corrosion resistance to air and salt
water. It is an easily welded, tough alloy that responds well to anodizing.
7075-T6: the strongest aluminum alloy with strength comparable to many steels.
Harken uses 7075-T6 in its Grand Prix cylinders which are built to handle extremely
high loads at minimal weight. A vigorous maintenance schedule is required when
using this alloy, because corrosion resistance is lower than 6061-T6. Available in
hardcoat or clear-anodized finishes.
Bearings
Bearing properties are functions of contact area, material type, bearing cages,
and whether the bearing rolls or slides. Caged
rollers
Types Delrin Torlon Stainless
balls
balls
balls
Ball bearings: very low-friction; low/medium-load capacity. Uncaged
rollers
Roller bearings: low-friction; high-load capacity. Bearing effi ciency (low-friction)
Sleeve bearings: medium/high-friction; extremely high-load capacity.
Sleeve
Materials bearing
Stainless steel is stronger than Torlon thermoplastic and Torlon is stronger than
®
Delrin acetal resin. Because stainless is heavier and usually higher maintenance, Bearing load capacity
®
Torlon is used in most high-load applications.
Contact Area
More contact between the bearing and the race increases friction, but also increases
load capacity. Balls are loaded on small points, cylindrical rollers are loaded along their
length, and sleeve bearings are curved around the shaft so a large portion is in contact.
Ball bearing
Unlike balls and cylinders, sleeves are not prone to being flattened by extreme or static Roller bearing contact area
contact area
loads because they already conform to the curvature of the shaft.
Motion (rolling, caged rolling, or sliding)
Sliding bearings (known as sleeve, plain, full-contact, bushing, or journal bearings) are
very high strength, but have nothing to reduce friction between contact areas. At most,
they have a low-friction sleeve between the surfaces. Rollers and balls avoid almost all
of this friction because they do not slide against the race, though they can come in contact
with each other. Caged roller bearings are separated from each other to avoid this.
Caged Bearings
Caged bearings are roller bearings held in a cage that keeps them separated from Caged rollers Uncaged rollers
each other and parallel to reduce friction. Caged bearings are used in winches and
Black Magic blocks.
Captive Bearings
Captive bearings are ball bearings that are contained so they won't spill during
product maintenance. Black Magic blocks have ball bearings held captive by the
lip of the sheave. CB traveler cars feature ball bearings held captive by a wire guide.
Carbo
Carbo Air blocks feature lightweight, fiber-reinforced, nylon-resin sideplates with a
60% higher MWL than stainless-reinforced Classic blocks. Lightweight fiber-reinforced
Carbo-Cams are ideal for racing where weight is critical. The Carbo name comes from CB traveler Black Magic sheave
an additive that gives blocks their color and UV-resistance.
Carbon Black
Carbon black is a color additive used in black Delrin ball bearings, block sheaves,
and sideplates to protect against UV exposure.

Carbo Air block

For complete listing, see www.harken.com/glossary Carbo-Cam cleat

Delrin is a registered trademark of E. I. du Pont de Nemours and Company or its affiliates.
Torlon is a registered trademark of Solvay Advanced Polymers, L.L.C.
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