distribution system which controls the reciprocating motion of the piston is
arranged on the cylinder wall, and the valve distribution is automatically
supplied when the piston moves.
(2) According to the rated working pressure of DTH hammer, pneumatic DTH
hammer can be divided into low wind pressure DTH hammer and medium and
high wind pressure DTH hammer. Low wind pressure DTH hammer generally
refers to its rated working pressure ranging from 0.5 to 0.7 MPa, such as CIR
series produced by Yihua Ingersoll-Rand Mine Construction Machinery Co.,
Ltd., WC and DJ series produced by Wuxi Prospecting Machinery Factory.
Medium and high wind pressure DTH hammer refers to DTH hammer with
working pressure above 0.7 MPa, such as DH and DHD high wind pressure
series produced by Yihua Ingersoll-Rand Mine Construction Machinery Co.,
Ltd., CJ2, GQ and CJ series produced by Wuxi Prospecting Machinery Factory,
JW and JG series produced by Jiaxing Metallurgical Machinery Factory. In
general, the DTH hammer with working pressure of 0:7 $ 1:2 MPa is called
medium wind pressure DTH hammer, and the DTH hammer with working
pressure above 1:2 MPa is called high wind pressure DTH hammer.
(3) According to the drilling diameter of DTH hammer, it can be divided into small
diameter DTH hammer and large diameter DTH hammer. The hole diameter
below 200 mm is called small diameter DTH hammer, such as CIR90, CIR110,
CIR150, CIR170, J-80, J-80B, J-100, J-100B, and J150 series. The hole
diameter larger than 200 mm is called large diameter DTH hammers, such as
DH, DHD, CJZ, JW-200, J-200B, J-250, and FGC-15 series.
Fig. 11.3 Structural schematic diagram of valve-type pneumatic DTH hammer (1—Upper
connector, 2—Check valve; 3—Adjusting washer; 4—Valve plate; 5—Valve seat; 6—Piston;
7—Outer cylinder; 8—Inner cylinder; 9—Bushing; 10—Brazing jacket; 11—Round key;
12—Drilling bit)
Fig. 11.4 Structure schematic diagram of valveless pneumatic DTH hammer (1—Joint;
2—Check valve; 3—Valve seat; 4—Inner cylinder; 5—Piston; 6—Outer cylinder; 7—Bushing;
8—Card key; 9—Spline sleeve; 10—Drilling bit)
11.2 Principle and Classification of Pneumatic DTH Hammer
199
arranged on the cylinder wall, and the valve distribution is automatically
supplied when the piston moves.
(2) According to the rated working pressure of DTH hammer, pneumatic DTH
hammer can be divided into low wind pressure DTH hammer and medium and
high wind pressure DTH hammer. Low wind pressure DTH hammer generally
refers to its rated working pressure ranging from 0.5 to 0.7 MPa, such as CIR
series produced by Yihua Ingersoll-Rand Mine Construction Machinery Co.,
Ltd., WC and DJ series produced by Wuxi Prospecting Machinery Factory.
Medium and high wind pressure DTH hammer refers to DTH hammer with
working pressure above 0.7 MPa, such as DH and DHD high wind pressure
series produced by Yihua Ingersoll-Rand Mine Construction Machinery Co.,
Ltd., CJ2, GQ and CJ series produced by Wuxi Prospecting Machinery Factory,
JW and JG series produced by Jiaxing Metallurgical Machinery Factory. In
general, the DTH hammer with working pressure of 0:7 $ 1:2 MPa is called
medium wind pressure DTH hammer, and the DTH hammer with working
pressure above 1:2 MPa is called high wind pressure DTH hammer.
(3) According to the drilling diameter of DTH hammer, it can be divided into small
diameter DTH hammer and large diameter DTH hammer. The hole diameter
below 200 mm is called small diameter DTH hammer, such as CIR90, CIR110,
CIR150, CIR170, J-80, J-80B, J-100, J-100B, and J150 series. The hole
diameter larger than 200 mm is called large diameter DTH hammers, such as
DH, DHD, CJZ, JW-200, J-200B, J-250, and FGC-15 series.
Fig. 11.3 Structural schematic diagram of valve-type pneumatic DTH hammer (1—Upper
connector, 2—Check valve; 3—Adjusting washer; 4—Valve plate; 5—Valve seat; 6—Piston;
7—Outer cylinder; 8—Inner cylinder; 9—Bushing; 10—Brazing jacket; 11—Round key;
12—Drilling bit)
Fig. 11.4 Structure schematic diagram of valveless pneumatic DTH hammer (1—Joint;
2—Check valve; 3—Valve seat; 4—Inner cylinder; 5—Piston; 6—Outer cylinder; 7—Bushing;
8—Card key; 9—Spline sleeve; 10—Drilling bit)
11.2 Principle and Classification of Pneumatic DTH Hammer
199