Lubrication of DTH Drill Bit
Because of the bad working conditions of the DTH Drill Bit, which has both a large dust content and a high humidity, and the reciprocating movement of the piston has a higher frequency and a larger impact velocity, the lubrication of the impacter is very important.
(1) Purpose of air chamber impacter lubrication The purpose of impacter lubrication is roughly three:
1) Reduce the friction loss of moving parts.More serious is due to insufficient lubrication caused by excessive friction, will make the contact surface produce fine summer clothing, such as crack expansion will cause damage to parts.In addition, the surface overheating caused by excessive friction will cause local softening and plastic deformation of the metal, which will eventually lead to the destruction of the cylinder and piston.
2) anti-corrosion effect.The heat shock parts are easily corroded by the chemical substances in pressurized gas and water during drilling, and the corrosion occurs simultaneously with the stress in the parts.Will make the parts of strong crossing serious decline;Corrosion will also make the crack further expand or the corrosion pit rust area directly caused by the damage of parts, so, corrosion prevention is one of the important functions of lubrication;
3) Sealing effect: suitable lubrication can ensure the sealing between the moving parts of the impactor and prevent the efficiency of the impactor from being reduced due to the poor sealing.
(2) the quality of lubricating oil requirements of the United States Gardner ~ Denver Compressed Air Research Institute has put forward eight requirements for the lubrication of the wind engine:
1) Must have high liquid film strength;
2) can not easily erupt or interfere with the movement of the valve disc;
3) there can be no smoke and poison gas discharge;
4) No corrosion under any conditions;
5) can quickly lubricate all parts to be lubricated;
6) Fully lubricated at high ROP, high and low temperatures;
7) No sticky residue is formed in either cold gas or hot gas;
8) It has high oil quality.