Full-hole reverse circulation cluster-type down-the-hole (DTH) hammer with multiple independent hannels

Abstract

A full-hole reverse circulation cluster-type down-the-hole (DTH) hammer with multiple independent channels is provided. The DTH hammer includes a drill rod, a drill rod joint, a drill rod air pipe, a diversion chamber, at least one hammer, and an upper pressure plate, a lower pressure plate, and an upper outer hammer protection pipe for fixing the hammer, where at least one jet air pipe communicated with the diversion chamber and at least one drill cuttings discharge pipe are arranged between the hammers; lower ends of the jet air pipe and the drill cuttings discharge pipe are located close to a hammer drill bit; and the lower end of the jet air pipe is provided with jet holes for producing a negative pressure.

Claims

1. A full-hole reverse circulation cluster-type down-the-hole (DTH) hammer with multiple independent channels, comprising a drill rod, a drill rod joint, a drill rod air pipe, a diversion chamber, at least one hammer, and an upper pressure plate, a lower pressure plate, and an upper outer hammer protection pipe for fixing the hammer, wherein at least one jet air pipe communicated with the diversion chamber and at least one drill cuttings discharge pipe are arranged between the hammers; lower ends of the at least one jet air pipe and the at least one drill cuttings discharge pipe are located adjacent to a hammer drill bit; the lower end of the at least one jet air pipe is provided with jet holes for producing a negative pressure; and an airflow direction of the jet holes is at an inclination angle with axial and radial directions of a drill cuttings discharge hole, wherein after air is jetted out, a swirling negative pressure is formed to suck drill cuttings into the at least one drill cuttings discharge pipe; an inner protection pipe is provided at a periphery of an upper end of the drill rod; the inner protection pipe is nested inside an outer protection pipe; a bearing is provided between the outer protection pipe and the inner protection pipe to make the outer protection pipe and the inner protection pipe mutually rotatable; a circular drill cuttings discharge chamber is formed between the inner protection pipe and the outer protection pipe; a lower end of the drill cuttings discharge chamber is communicated with the at least one drill cuttings discharge pipe; a side of the drill cuttings discharge chamber is connected with a drill cuttings output pipe; the drill cuttings discharge chamber is provided therein with an arc-shaped drill cuttings discharge baffle above the at least one drill cuttings discharge pipe; and the arc-shaped drill cuttings discharge baffle is a detachable structure; the arc-shaped drill cuttings discharge baffle is located at an upper end of the inner protection pipe and takes on an outwardly bent arc; an outer flange is fixed to the drill cuttings discharge hole at a bottom of the at least one drill cuttings discharge pipe; the outer flange is circular and comprises a serrated lower end; a roller shaft is fixed in a diameter direction of the serrated lower end of the outer flange; the roller shaft is provided with a rotatable roller; and the rotatable roller comprises a serrated diametric surface and protrudes slightly from the outer flange; and when the DTH hammer is working, the DTH hammer slowly rotates in a circumferential direction; the serrated rotatable roller provided at the drill cuttings discharge hole contacts a bottom of a borehole and rotates due to a frictional resistance of a rock surface at the bottom of the borehole, the drill cuttings accumulated at the drill cuttings discharge hole move into the at least one drill cuttings discharge pipe; and the drill cuttings are discharged due to the negative pressure.

2. The full-hole reverse circulation cluster-type DTH hammer with multiple independent channels according to claim 1, wherein the at least one jet air pipe and the at least one drill cuttings discharge pipe are in a one-to-one correspondence and evenly distributed between the hammers; and the airflow direction of the jet holes is at a 5-30? inclination angle with the axial and radial directions of the drill cuttings discharge hole.

3. The full-hole reverse circulation cluster-type DTH hammer with multiple independent channels according to claim 1, wherein 2 to 8 jet holes are arranged at a bottom of each jet air pipe.

4. The full-hole reverse circulation cluster-type DTH hammer with multiple independent channels according to claim 1, wherein the rotatable roller is fixed to the roller shaft through a small sleeve; and a baffle is provided between the roller shaft and the outer flange to fix the roller shaft.

5. The full-hole reverse circulation cluster-type DTH hammer with multiple independent channels according to claim 1, wherein the rotatable roller comprises two serrated ends and a central circumferential groove.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] FIG. 1 is a front sectional view of a hammer part according to the present disclosure;

[0025] FIG. 2 is a top sectional view of the hammer part according to the present disclosure;

[0026] FIG. 3 is a front sectional view of a drill cuttings discharge hole part according to the present disclosure;

[0027] FIG. 4 is a bottom sectional view of the drill cuttings discharge hole part according to the present disclosure;

[0028] FIG. 5 is a front sectional view of a main body structure according to the present disclosure;

[0029] FIG. 6 is a structural diagram of a drill cuttings discharge chamber of a drill cuttings discharge mechanism according to the present disclosure;

[0030] FIG. 7 is a structural diagram of a drill cuttings discharge hole of the drill cuttings discharge mechanism according to the present disclosure; and

[0031] FIG. 8 is a structural diagram of an anti-clogging mechanism of the drill cuttings discharge mechanism according to the present disclosure.

[0032] Reference Signs: 1. drill rod joint; 2. upper outer hammer protection pipe; 3. drill rod air pipe; 4. upper pressure plate; 5. diversion chamber; 6. lower outer hammer protection pipe; 7. jet air pipe; 8. hammer; 9. lower pressure plate; 10. hammer drill bit; 11. drill cuttings discharge pipe; 12. jet hole; 13. drill rod; 14. drill cuttings discharge chamber; 15. drill cuttings output pipe; 16. outer protection pipe; 17. bearing; 18. drill cuttings discharge baffle; 19. inner protection pipe; 20. outer flange; 21. roller shaft; 22. roller; 23. small sleeve; 24. baffle; and 25. DTH hammer.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] The present disclosure is described in detail below according to FIGS. 1 to 8.

[0034] As shown in FIGS. 1 to 8, the present disclosure provides a full-hole reverse circulation cluster-type DTH hammer with multiple independent channels. The DTH hammer includes drill rod (13), drill rod joint (1), drill rod air pipe (3), diversion chamber (5), at least one hammer (8), and upper pressure plate (4), lower pressure plate (9), and upper outer hammer protection pipe (6) for fixing the hammer (8). In the present disclosure, there are 9 hammers, including 6 hammers located at a periphery and 3 hammers located in a center. The drill rod air pipe (3) provides power to each hammer through the diversion chamber (5).

[0035] There are three independent drill cuttings discharge systems located between the hammers. Each of the drill cuttings discharge systems includes jet air pipes (7) connected with the diversion chamber (5), drill cuttings discharge pipes (11), and drill cuttings discharge chamber (14) located above the drill cuttings discharge pipes (11).

[0036] A lower structure of the drill cuttings discharge system is shown in FIGS. 3 to 5. Lower ends of the jet air pipes (7) and the drill cuttings discharge pipes (11) are located close to hammer drill bit (10). The lower end of each of the jet air pipes (7) is provided with jet holes (12) for producing a negative pressure. Specifically, a bottom of each of the jet air pipes (7) is provided with 6 jet holes (12). An airflow direction of the jet holes is at a 10? inclination angle with axial and radial directions of a drill cuttings discharge hole. Thus, after the air is jetted out, a swirling vacuum is formed, and the drill cuttings are discharged through the drill cuttings discharge pipe (11).

[0037] An upper structure of the drill cuttings discharge system is shown in FIGS. 5 and 6. Inner protection pipe (19) is provided at a periphery of an upper end of the drill rod (13). The inner protection pipe (19) is nested inside outer protection pipe (16). bearing (17) is provided between the outer protection pipe and the inner protection pipe to make the outer protection pipe and the inner protection pipe mutually rotatable. Circular drill cuttings discharge chamber (14) is formed between the inner protection pipe and the outer protection pipe. A lower end of the drill cuttings discharge chamber (14) is communicated with the drill cuttings discharge pipes (11). A side of the drill cuttings discharge chamber (14) is connected with drill cuttings output pipe (15). The drill cuttings discharge chamber (14) is provided therein with arc-shaped drill cuttings discharge baffle (18) above the drill cuttings discharge pipes (11). The drill cuttings discharge baffle (18) is a detachable structure.

[0038] A bottom structure of the drill cuttings discharge system is shown in FIGS. 7 and 8. Outer flange (20) is fixed to the drill cuttings discharge hole at a bottom of each of the drill cuttings discharge pipes (11). The outer flange is circular and includes a serrated lower end. Roller shaft (21) is fixed in a diameter direction of the lower end of the outer flange. The roller shaft (21) is provided with one rotatable roller (22). The roller protrudes slightly from the outer flange. The roller is fixed to the roller shaft through a small sleeve. A baffle is provided between the roller shaft and the outer flange to fix the roller shaft. The roller includes two serrated ends and a central circumferential groove. This structure can easily drive large drill cuttings, making them enter the drill cuttings discharge pipe smoothly.