turning chuck / hydraulic / expandable

Coils are loaded on the expanding mandrels to be held firmly in place during the uncoiling and coiling process. Fives offers a wide range of mandrels specially designed for these operations.

"Reverse pyramid" shaft mandrels
Compared to a standard pyramid mandrel (expand when pushed), reverse pyramid mandrels (expand when pulled) offer the following advantages.

Compressive stress is applied on segments instead of tensile stress, so the system significantly reduces the risk of segments breakage and this simplifies the connection between the gearbox and the mandrel.
The pyramid shaft is under tensile force, limiting the risk of bending.
The entire mandrel (shaft and segments) can be dismounted without taking apart the expanding hydraulic cylinder, saving maintenance time.
The entire hydraulic cylinder can be dismantled without dismounting the mandrel or the pyramid shaft.
Pyramids are automatically greased, to reduce mandrel wear and no blockages occur when the mandrel retracts.
The mandrel's diameter is continuously monitored to ensure normal behavior during operation.