Hydraulic support jack

φ63, φ80, φ100, φ110, φ125, φ140, φ160, φ180, φ200, φ210, φ220, φ230, φ250, φ280, φ300

The bottom lifting jack is an auxiliary support component in the hydraulic support (coal mine fully mechanized mining equipment). It is mainly used to solve the problem of "gnawing the bottom" or "crushing" caused by the support base sinking into the bottom plate (especially soft bottom coal or the bottom plate softened by water). By lifting the front or rear end of the base upward, the resistance of the moving frame is reduced and the smooth forward movement of the support is ensured.

Working principle

Bottom lifting action:

The hydraulic system supplies fluid to the jack piston rod chamber (lower chamber). The high-pressure oil pushes the piston rod downward. After the end pad is pressed against the bottom plate, the reaction force of the piston rod is transmitted to the base through the cylinder, lifting the base (similar to the "lever fulcrum" principle).

Reset action:

Spring return: Some models are equipped with a return spring in the cylinder. After the hydraulic pressure is removed, the spring pushes the piston rod to retract and the base falls back.

Hydraulic pressure reset: The spring-less structure requires fluid to be supplied to the upper chamber of the cylinder to force the piston rod to retract (suitable for large load scenarios).

Linkage control:

Usually used in conjunction with a push jack, the process is: 1. Lift the base with the bottom jack → 2. Move the pull frame of the push jack forward → 3. Reset the bottom jack → 4. Re-tighten the top plate with the bracket.