The different characteristics of the shield caving power support with a special canopy and two-legged caving power support have been studied.

Mainly introduces one kind system design method of the support and shield type hydraulic pressure support for the coal bed of thickness 3.

One kind system design method of the support and shield type laying down top coal hydraulic pressure support was introduced,including the design procedures of the choice of hydraulic pressure support types,the basic parameter determination,the design of four link motion gear,the overall stress analysis of hydraulic pressure support and the column parameter determination and so on.

By calculating the load-carrying ability,the angle between the canopy and the shield,and the stroke of the stubilising ram,the peper makes a detailed study of influences of the connection position dimensions on performances of two-leg shield supports using computer simulation analysis, and lays the theoretical foundation for designing the rational connection position dimensions.

Balance ram is a key component of a two-leg shield support.

Taking a two-leg shield support as an example,this paper presents the theory of the shield supporting ability areas.

The article elaborate on a strong point of ZY6000-25/45 hydraulic shield support,which is increasing useful time of upright post,meet the needs of traffic condition and geological condition,proving two plan of technical reform of ZY6000-25/45 hydraulic shield support.

In order to solve the problem of support-strata worsening induced by improper supporting in top-coal caving working face,the role of equilibrium jack in adaptability of 2-leg shield support is studied.