Constant-resistance contractible flexible support device and roof cutting gob-side entry retaining blocking gangue support system

Abstract

The invention relates to the technical field of coal mining, in particular to a constant-resistance contractible flexible support device and a roof cutting gob-side entry retaining blocking gangue support system. The constant-resistance contractible flexible support device comprises a cylinder body, a rod body and a supporting part; the cylinder body comprises a tray, a straight cylinder part anda conical cylinder which are sequentially connected; a guiding rod is formed in the straight cylinder part, one end of the guiding rod is fixed to the tray, and the other end of the guiding rod extends into the conical cylinder; the inner diameter and the outer diameter of the conical cylinder are gradually increased from the end connected with the straight cylinder part to the other end; the rodbody comprises a cone head and a straight rod, and a guiding hole is formed in the rod body; and the cone head is connected into the conical cylinder in matched and sleeved modes, and the guiding rodis inserted into the guiding hole in a matched mode. The device has certain receding characteristics in the vertical direction, vertical pressing, bending and damage are avoided, the large working resistance can be maintained to support a top plate, and the flexible support device and the roof cutting gob-side entry retaining blocking gangue support system are especially suitable for a roof cutting gob-side entry retaining project prone to generating surrounding rock large deformation, and can lay the foundation for successful implementation of roof cutting gob-side entry retaining of deep orthick coal seams.

Description

technical field [0001] The application relates to the technical field of coal mining, in particular, to a constant-resistance shrinkable flexible support device and a roof-cutting gob-side roadway retaining gangue-retaining support system. Background technique [0002] Roof cutting and goaf retaining is a new type of coal pillar-free mining technology, which cuts off the mechanical relationship between the roof of the goaf and the roof of the roadway within a certain height, and makes full use of the mine pressure and the characteristics of the crushing and expansion of the goaf to automatically form roads and optimize The roof structure is improved, the surrounding rock stress is improved, and roadside filling is canceled, the cost of roadway retention is reduced, and the normal mining of the working face is not affected, which is more suitable for modern high-intensity mining requirements. [0003] After the top-cut gob-side entry is stabilized, the pressure of the overlyi...

AI Technical Summary

Problems solved by technology

Gangue roadsides are mainly maintained and controlled by roadside gangue retaining and supporting devices. Under normal geological conditions, rigid support is often used for roadside gangue retaining and better results can be obtained, while deep roof cut roadways have a significant impact on dynamic pressure. The thick coal seam working face has a large mining space and severe mine pressure. At this time, the roof and floor move closer, and the stop bar structure is arranged on the side of the kerf. The roof sinking of the kerf side is more obvious than that of the solid coal side. Rigid support The device often bends and breaks due to vertical compression due to the inability to coordinate deformation with the top and bottom plates, thus losing the ability to block and support the gangue, resulting in serious deformation of the gangue gang, and even failure to retain the roadway

[0004] In the existing technology, rigid I-steel or shrinkable U-steel is often used for roadway retaining along the gob-side roadway. Rigid I-steel is generally only suitable for shallow and thin coal seams, because shallow thin coal seams retain The approach of the roof and floor of the roadway is small, and the use of rigid I-beams can achieve better results; deep and thick coal seams cut the roof and retain roadways along the gob because of the large amount of roof and floor movement, and the rigid support is often damaged by compression and bending, so it is often Shrinkable U-shaped steel is used for gangue support. During operation, the two sections of U-shaped steel slide relative to each other to achieve the effect of retractable displacement. However, this device has a disadvantage that the relative sliding force of the two sections of U-shaped steel is determined by the degree of tightness of the cable. Yes, when the sliding force of the device is set too large, the U-shaped steel will be bent and deformed by the pressure of the roof, thus losing the effect of blocking gangue. Therefore, the setting value of the sliding force of the shrinkable U-shaped steel is generally small, and basically has no effect on the roof. The support function only plays the role of laterally resisting the gangue in the goaf, and the degree of tightness of the cable cannot be directly quantified as the vertical sliding value of the device. The setting of the sliding force can only be obtained through repeated field tests.

Images