Abstract
We have analyzed the formation of corrosion damages during the standby time of a rock bit in operation and the low crack resistance of high-strength steel under the action of aqueous environment, which lead to the loss of serviceability of the rolling friction pair of the rock bit. We have investigated the relation between the structure of 55SM5FA high-strength steel, used for rollers of the rock-bit bearings, and its short-term crack resistance with regard for the influence of water on it. With decrease in the fracture toughness of steel, the negative influence of environment on its crack growth resistance increases. The optimal structure of steel for rollers is fine-grained martensite with ~ 1% of troostite and hardness HRC 56 to 58. To retard the stress corrosion fracture of rock bits, we recommend conserving them during standby times in the boring process by lubrication not only of the nipple part, but also of the open bearings of bits.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
