WorldWide Drilling Resource

Hammer Time! Adapted from Information by Drill King International Down-the-hole (DTH) air hammers use air to make the piston strike the bit, producing a very high load during impact. The result is a method which can drill through extremely hard formations. This is a different process from rotary drilling, which uses weight and rotation to penetrate softer formations. Drill King DTH air hammers have a unique airflow design which maximizes performance and provides more power down the hole. The pneumatically operated valveless percussion drills are capable of being mounted on many different types of drilling machines which utilize a top-head or kelly drive mounting con- figuration. The drill rig must be capable of maintaining a sufficient amount of air pressure and volume, lubrication, torque, rotations per minute (rpm), hold-down, and holdback. Exhaust air from the hammer is passed through blowholes in the drill bit to flush clean the drilled hole. Rotation occurs from the drive motor at the top of the drill string; however, this is not to be confused with the rotary drilling method. Feed force is transmitted to the hammer via the hold down unit and weight of the drill pipe. The Drill King Hammer Line is designed to allow the wear sleeve to be manufactured with increased wall thickness, extending the service life. The company’s hammers are used in many different applications, including heavy construction, gas and oil, mining, and water well. The Heavy Duty (HD) hammer is ideal for enhanced wear protection in hard, abrasive formations. For mining customers, this is the preferred hammer. The HD hammer line utilizes the same internal parts as standard hammers, so converting between the two is relatively simple. Drill King offers kits to aid in extending the life of all their hammers, giving customers a maximized return on product investments. Hammer repair kits can help save time and money by supplying the integral internal wear components in one easy-to-install kit. Hammer rebuild kits are available when external parts of the hammer need to be replaced. Hammer seal kits are recommended with every new hammer since seals must be replaced at regular intervals to maintain air pressure and operate the hammer efficiently. 42 NOVEMBER 2018 WorldWide Drilling Resource ® WTR