A key source of damage to DTH hammers (apart from wear and tear) is insufficient lubrication. DTH hammers function in some of the worst environmental conditions encountering extreme heat, variable PH levels, salinity and a broad range of rock formations containing acidic and basic chemical compositions.
This extreme operating environment can lead to pitting and weakening of the metal components, causing premature failure of the hammer components. Adequate water injection utilizing clean water and correct oil injection rates will help to reduce the abrasive and chemical effects of ground conditions encountered.
The use of line lubricator is of extreme importance for an optimum operating efficiency of a DTH hammer, since it prevents the main causes of deterioration and premature failure of the hammer.
The DS450 Automatic Lubricator (Oiler) has a positive displacement pump that is air powered. The air gets to the pump through a solenoid valve. The solenoid valve gets a signal from an electronic timer that has a variable frequency set by the operator. Each pulse from the timer results in 1⁄2 cubic inch of oil. The pressure ratio between air supplied to the pump and oil coming out of the pump is about 4-1⁄2 to 1. This enables 100 PSI of air to push 450 PSI of oil. When the electronic signal is off, the pump recharges by means of a return spring in the pump. This simple system is durable and dependable.
A diagram on the face of the 7-1⁄2 gallon tank tells the operator the recommended amount of oil to use with the air volume he has available. It then shows where to set the knob for the desired amount of oil.