ABOUT ROTARY BOREWELL DRILLING

If mud cake is not shaped thoroughly → water from mud goes in → water is available in contact with clay/shale → hydration → so measurement improves → but there's no space to support this: excess weight cannot be supported which bulge breaks from within → bit by bit this caving keeps on growing. The cuttings are taken out using a bailer

In DTH drilling, the percussion mechanism – generally known as the hammer – is situated specifically above the drill little bit. The drill pipes transmit the necessary feed power and rotation to your hammer and the little bit, together with the fluid (air, water or drilling mud) utilized to actuate the hammer and flush the cuttings. Geophysica