the drilling efficiency of large diameter pneumatic DTH hammer is one of the
key problems.
(2) Air compressors are not easy to match. Because of the large borehole diameter
and the large amount of air needed for slag discharge, the need for both large air
volume and high air pressure will increase the investment of air compressor
equipment and the energy consumption of air compressor. Conventional
medium and low air pressure air compressors will not be able to be used
together, which directly affects the popularization and application of this
technology.
(3) It is difficult to manufacture and assemble. Large diameter drilling requires
large-size DTH hammer impactor. Large-size equipment is difficult to manufacture and assemble.
(4) The mechanism and process of pneumatic DTH hammer impactor are complex.
At present, there are few studies on the pneumatic mechanism of impactor at
home and abroad. The pneumatic principle, thermodynamic mechanism, critical
sonic flow process and aerodynamic matching parameter relationship involved
in the impact process need to be studied in depth, and the design method of the
impactor system is urgently needed.
11.3 Principle and Parameter Design of Large Diameter
Pneumatic DTH Hammer Impactor
Referring to the design methods and ideas of foreign products, the principle and
design method of large diameter pneumatic DTH hammer impactor are introduced,
including selecting the structure type of DTH hammer, putting forward the
appropriate calculation method of performance parameters, designing the parameters of key parts, and drawing parts and overall assembly drawings.
11.3.1 Design Requirements
Referring to the large diameter pneumatic DTH hammer of Korea Dongyu
Machinery Co., Ltd., the design method of 600 mm large diameter pneumatic DTH
hammer impactor is analyzed. The impactor is the power tool to produce impact
power and frequency, and is the most important component of DTH hammer. The
quality of impactor directly affects the efficiency, quality, cost, and safety of drilling. In order to obtain a reasonable and advanced design scheme, it is necessary to
conduct a comprehensive and in-depth analysis of various requirements. According
to the design objectives of DTH hammer impactor, the primary and secondary
requirements should be distinguished and coordinated, so as to centralize and unify
the requirements of all aspects as far as possible.
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11 Pneumatic Down-the-Hole Hammer
key problems.
(2) Air compressors are not easy to match. Because of the large borehole diameter
and the large amount of air needed for slag discharge, the need for both large air
volume and high air pressure will increase the investment of air compressor
equipment and the energy consumption of air compressor. Conventional
medium and low air pressure air compressors will not be able to be used
together, which directly affects the popularization and application of this
technology.
(3) It is difficult to manufacture and assemble. Large diameter drilling requires
large-size DTH hammer impactor. Large-size equipment is difficult to manufacture and assemble.
(4) The mechanism and process of pneumatic DTH hammer impactor are complex.
At present, there are few studies on the pneumatic mechanism of impactor at
home and abroad. The pneumatic principle, thermodynamic mechanism, critical
sonic flow process and aerodynamic matching parameter relationship involved
in the impact process need to be studied in depth, and the design method of the
impactor system is urgently needed.
11.3 Principle and Parameter Design of Large Diameter
Pneumatic DTH Hammer Impactor
Referring to the design methods and ideas of foreign products, the principle and
design method of large diameter pneumatic DTH hammer impactor are introduced,
including selecting the structure type of DTH hammer, putting forward the
appropriate calculation method of performance parameters, designing the parameters of key parts, and drawing parts and overall assembly drawings.
11.3.1 Design Requirements
Referring to the large diameter pneumatic DTH hammer of Korea Dongyu
Machinery Co., Ltd., the design method of 600 mm large diameter pneumatic DTH
hammer impactor is analyzed. The impactor is the power tool to produce impact
power and frequency, and is the most important component of DTH hammer. The
quality of impactor directly affects the efficiency, quality, cost, and safety of drilling. In order to obtain a reasonable and advanced design scheme, it is necessary to
conduct a comprehensive and in-depth analysis of various requirements. According
to the design objectives of DTH hammer impactor, the primary and secondary
requirements should be distinguished and coordinated, so as to centralize and unify
the requirements of all aspects as far as possible.
206
11 Pneumatic Down-the-Hole Hammer