FLAT JACKS
Low height steel capsule jacks
The Structural Engineer's Solution for Temporary & Permanent Load Transfer

General Description

Flat Jacks consist of a mild steel capsule, circular in plan, with a cross section that is initally dumb-bell shaped. The dished portions are fitted with ground steel thrust plates before the jack is placed between the surfaces to be jacked apart. When the jack is inflated with a liquid the hydrostatic pressure is transmitted by the flat portions of the capsule through the thrust plates, while the toroidal rim of the jack deforms to allow the flat faces to move apart.

The maximum operating pressure is only 150 bar (2,200psi). Flat Jacks thereby exert low bearing pressures on the jacked faces.

The maximum recommended opening stoke of a flat jack is equal to the depth of the toroidal rim - about 25mm (1in).

Two pipe connections are welded into the jack rim usually at 90º to one another. One provides the inlet for inflation and the other serves as a vent during filling and is subsequently capped off.