Button bit has the characteristics of free button distribution, fast drilling speed, and a long grinding cycle, and is widely used in mining, railways, hydropower, and geological departments. Therefore, the service life of button bit directly affects the cost and efficiency of rock drilling.
The factors that affect the service life of button bit are not only related to the quality of processing and manufacturing but also closely related to the rock type, rock drilling model, grinding system, and operator proficiency. At the same time, it is possible to improve the service life of button bit by improving the factors affecting its service life.
Since the rock conditions vary greatly, the requirements for the type of rock drill bits are also different. Combining with the specific conditions of the rock, choosing suitable products is an important way to improve the service life of rock drill bits.
Any type of rock drill bit has a certain range of applications. The design of the rock drill bit must consider the rock and the type of rock drill it acts on. Due to the diversity of rocks, models, and their combinations, it is impossible to consider them all during design. However, a broad classification of rock drill bits is achievable, depending on the drillability and abrasiveness of the rock.
The service life of the button bit depends largely on the carbide fixing force. However, regardless of the button-fixing process, it is necessary to ensure that the rock drill bit does not lose its button in use. Therefore, there is a need for continuous research on the tooth fixation process of button bits.
It is mainly related to the application of new technologies by rock drill bit manufacturers, the level of new technology, and the problems existing in quality management.
In the mass production of rock drill bits, steel grades with high fatigue resistance, good rigidity and toughness, impact resistance, wear resistance, and good heat treatment performance are actively used. At the same time, it is necessary to improve the technical performance of button bit, which is necessary to improve the service life of button bit.
Strengthen the quality inspection and control of rock drill bit production
For rock drill bits with good quality and long service life, in addition to material and new technology, the main reason is that each process is done carefully, and the quality inspection and control are strict during processing.
In the “bottom-type induction brazing”, each button hole is measured precisely, buttons and holes are carefully cleaned, brazing is done carefully, and the frequency of induction current, brazing temperature, and heating time is strictly controlled to ensure that a batch of rock drill bits is produced with the same mechanical properties. When the pressure fit is fixed, the button holes require extremely strict accuracy, measured one by one, graded according to the size of the tolerance, and then the alloy teeth are similarly graded according to the need for the interference value, and the teeth and holes are aligned to keep the interference value within the required range, to ensure that no dislodgement occurs in use.
The service life of rock drill bit is determined by two factors: the inherent quality of rock drill bit and the scientific use method. If the quality of the rock drill bit is poor, no matter how carefully it is used, it will not help. Conversely, if a good rock drill bit is not used by scientific methods, it will also be scrapped prematurely.
The following 4 suggestions can be referred to.
① Under specific rock drilling conditions, the variety and specifications of rock drill bit should be selected reasonably through a comprehensive analysis of technology and economic benefits.
② Remove the drill bit correctly. Using the unloader to unload the brazing is beneficial to the improvement of the service life of rock drill bits.
③ Reasonable grinding of rock drill bit.
④ Choose the drill rod reasonably.
