Design Optimization and Performance Analysis of the Pneumatic DTH Hammer with Self-Propelled Round Bit

<div>Main parts of the pneumatic DTH hammer with the self-propelled round bit: 1, drill bit; 2, driver sub; 3, bit retainer ring; 4, piston; 5, hammer casing; 6, spiral nut; 7, inner cylinder; 8, spiral rod; 9, air distributor; 10, thrust ball bearing; 11, rotary joint; 12, connector; 13, valve; 14, top sub.</div>

Shock and Vibration

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Figure 1

Figure 1: Design Optimization and Performance Analysis of the Pneumatic DTH Hammer with Self-Propelled Round Bit 