English to Russian Tech/Engineering Automotive / Cars & Trucks lift axles

Traditional lift axle systems have been controlled by two pairs of rubber bellows working together to either lower or raise the axle. Of the two bellow pairs, one is pressurised and the other vented depending on whether or not the particular axle to which they are fitted is required to be in use. Typically systems are controlled through a pair of three-way, pilot-operated ***brake relay valves each controlling one of the bellow pairs. Brake relay valves offer high flow and are proven in the demanding commercial vehicle environment. Industrial spool valves have also been used but have suffered from durability and freezing issues.

Речь идет о подъемных мостах, вроде бы никакого отношения к тормозной системе нет, и что здесь означает "break", непонятно.

Спасибо!