Since the rock drilling process of the drill rod is complex, its force situation is very complicated, the use environment is harsh, and the length of service life is affected by many factors such as the power and air pressure of the rock drill, the cooperation between the drill bit and drill rod, the change of rock hardness, whether the user is a standardized operation and the operation level, so the failure form of drill rod and the parts of failure are various. When abnormalities occur, we can analyze and judge the situation, target processing, and improvement, ensure product quality and standardized operation, and make full use of the drill rod‘s ability.
From the previous article, we have learned that the forms of failure of light shank rods are shank rounding, shank fracture, drill shoulder fracture, rod fracture, thread fracture, early wear of the thread, etc. We also understand the causes of the early failure of light shank rods, so how can we deal with or prevent its early failure?
Early wear and rounding of the edges and corners of the shank
Early wear and rounding of the edges and corners of the shank refer to the abnormal rounding of the shank of the light shank rod in the hexagonal rotating sleeve of the rock drill, resulting in the phenomenon that the drill rod can not rotate in the rock drilling and can not discharge powder drilling.
Measures
1. The drill rod and rock drill rotating brazing sleeve manufacturing and processing enterprises should strengthen the control and testing of the size of the drill rod shank on the side and the size of the hexagonal inside the rotating brazing sleeve according to the standard to ensure that its size meets the standard.
2. Drilling rod manufacturers can lengthen the length of the quenching and tempering of the shank of the drill rod, increase the hardened length of the shank, and improve its wear resistance.
Therefore, in the case of early wear and rounding of the edges and corners of the shank during use, the operator should conduct a preliminary inspection and judgment based on the above situation. If it is the size deviation of the shank of the drill rod, you can notify the manufacturer to deal with it; if it is the wear of the rotating sleeve or the size deviation, it is necessary to replace or select a rotating sleeve with a size that meets the standard in time.
Shank fracture
Shank fracture refers to the phenomenon that the drill rod breaks due to the fracture of the end face of the shank to the back R of the drill shoulder during the use of the rod.
Measures
1. The production of drill rods is strictly controlled according to the standards to ensure that the internal quality and external dimensions of drill rods meet the standard.
2. The operator who uses the drill rod pays attention to the change and grinding of the R size of the drill sleeve of the rock drill and the resharpening to ensure the cooperation between the drill sleeve and the shank of the drill rod. At the same time, pay attention to checking whether the drill supporter of the umbrella drilling rig is in good condition, effectively standardize the use of the drill supporter, and avoid large swings and bending of the drill rod during use.
Shoulder fracture
Shoulder fracture refers to the phenomenon that the drill rod fails due to the fracture of the shoulder part in use.
Measures
Production enterprises should control the quality of hollow steel smelting and rolling, reasonably design the forming die of the drill shoulder, ensure the deformation streamline of the drill shoulder, strictly control the temperature and time of forging and quenching, and tempering of the drill shoulder, and ensure the internal quality of the drill shoulder.
Rod fracture
Rod fracture refers to the breakage of the drill rod in the area between the front R of the drill shoulder and the thread root during use.
Measures
1. The production enterprise strictly implements the process and testing to ensure the internal quality of the drill rod.
2. The user strictly abides by the rock drilling operation procedures, standardizes the use of drill rods, and avoids bending and damage of drill rods.
Thread breakage and early wear
Thread fracture refers to the phenomenon that the drill rod fails due to thread fracture during use.
Early wear of the thread refers to the phenomenon that the drill rod cannot be used because of the abnormal wear and flattening of its threaded teeth in the process of use so that it cannot cooperate with the inner thread of the drill bit to drive the impact and rotation of the drill bit.
Measures
1. Drilling rod enterprises strengthen the execution supervision of the process, improve the thread size accuracy, heat treatment quality, and production according to the standard, and ensure cooperation between the drill rod and the drill bit.
2. Drill bit enterprises strengthen the execution supervision of the process, improve the dimensional accuracy of the drill bit thread and produce according to the standard, and ensure the cooperation between the drill bit and the drill rod.
3. The user should standardize the operation, strengthen the operation inspection, and replace the drill bit in time to minimize long-term empty drilling.
