BC Hydro Hollow Jack

Janox designed and manufactured the world’s largest hollow jack, for a seismic upgrade project at BC Hydro’s Seven Mile Dam near Trail, BC.

At full working pressure, the proprietary piston design maintains a constant extrusion gap, despite barrel deflection of 1/16″ on diameter. At 10,000PSI, the extension force is 4.4 million lbs, enough to lift a stack of 1,000 Ford F-150 pickup trucks!