1. DTH hammer relies on high pressure gas reciprocating driving the piston to move down at high speed to impact the drill bit to break the rock. DTH hammer has been widely used in the construction of water drilling rig and has the following advantages:
(1) low operating cost. DTH hammer requires drilling rig with low axial pressure, low rotation speed, low torque, low natural power consumption, relatively small diameter of drill pipe, easy installation and disassembly, and long service life.
(2) high drilling efficiency, long life of drilling tools, DTH hammer drilling rock drilling, the medium is air, no flushing medium recovery and treatment problems, reduce the auxiliary time.
(3) in the seriously lost strata and unstable pore wall strata, DTH hammer and casing tube drilling can be used to completely solve the problem of repeated operation.
(4) DTH hammer drilling water well, with relatively complete hole wall and no pollution of other media, can basically maintain the original formation structure and water permeability, reduce well washing time and save costs.
(5) since the DTH hammer uses air as the power source, it can be used in the cold winter construction, which greatly reduces the workload of cold prevention in the previous winter construction.
2.Indexes for DTH hammer :
Good hammer should have two indexes: long drilling tool life and high rock crushing efficiency.Previous studies have shown that it is not only the impact frequency and energy that affect the performance of the hammer, but also the weight, shape, stroke size and impact speed of the hammer.On the same hammer, the performance parameters are also interrelated and restricted.In determining the parameters of the hammer, they must be connected and matched.However, the impact drilling speed mainly depends on impact frequency, impact energy, impact mode and transmission.
3.The water well drilling rig should give priority to the following aspects in selecting the DTH hammer :
(1) Simple structure
(2) Reliable work and good performance
(3) Good processing and manufacturing process
(4) Easy to assemble and disassemble, easy to repair and replace spare parts
(5) Long service life
Drill bits for pneumatic hammer drilling:
A drill is a direct tool for breaking rock.Therefore, the reasonable design, manufacture and use of the drill bit to ensure the high quality and long life of the drill bit is an important link to improve the drilling technology of DTH.
According to the different physical and mechanical properties of rocks, the reasonable selection of different types of bits is an important technical condition to improve drilling efficiency and increase the service life of bits.
From the perspective of stress, the drill bit bears a large dynamic load and friction, so it is required that the drill bit body has a higher surface hardness, better wear resistance and sufficient impact toughness.According to the present situation, the types of bit used by the impactor include cylindrical tooth bit, blade bit and core bit.
4,Maintenance after use:
Proper and timely maintenance can extend the life of DTH hammer components and greatly reduce the operating cost.Timely cleaning of DTH hammer parts. In many cases, DTH hammer needs to be repaired and examined in more detail due to wear of outer casing or internal parts.If all parts are in good condition, then it is ok to apply lubricating oil and install it correctly according to the assembly diagram.However, in order to ensure the best performance of your DTH hammer, it is necessary to maintain the DTH hammer regularly.
5,Regular maintenance:
All equipment needs regular maintenance. Only when we do each maintenance carefully, can you be handy when you need to use it. DTH hammer is the same .If you have used DTH hammer for a long time then you need to follow the following steps to maintain DTH hammer regularly:
(1) replace all "o" rings, check valve seals and springs inside the DTH hmmer, which can ensure that the DTH hammer reduces gas consumption.
(2) ensure good lubrication of the internal moving parts (pistons) of the DTH hammer, and remove all sharp angles and burrs formed by the piston in the use process (it is suggested to grind off the sharp angles and burrs of the piston with oil stone).
(3) replace the outer casing and cylinder as needed.
(4) ensure that the check valve is free and correct in return.
(5) correct installation according to the installation sequence in the instruction manual or installation schematic diagram.
(6) keep it properly.
