From hanging a wall picture to building large scrappers or condominiums, Drilling is an inevitable process in the construction. This is a process of cutting a hole smoothly in shape on concretes, rocks, woods, floors, etc. Drill machines come in several shapes and sizes, from hand-held power machines to floor-mounted machines.
The machines have drill bits, which cuts the surface with a cross-section circular motion, made with hard metal. Drill bits are rotary cutting tool comes in different shapes as per the hole is required.
Mostly drill machines have two types of bits, percussive, which breaks rock or ground by chipping there intermittently, and rotary bits, which are used to cut or grind. Percussive drills work slower than rotary and are used mostly to make shallow holes. Rotary drills can be of pod-type drills and spiral drills. Now, drills bits have three classifications:
- Drag bits that are mostly used to make holes in soft rocks. This kind of bits cut rocks with more than one wings or tipped with tungsten carbide.
- Roller bits that are used for hard rocks. The cutting edge of these bits are teeth shaped.
- Diamonds bits that crush the rocks literally. This diamond bits make a round hole ending up with a cross-section sample of penetrated strata.
Elements of machines
All the Drilling machines have some characteristics in their construction.
- A spindle that holds the cutting bits and rotates it in a fixed proportion. In most of the drill machines, the spindle is joined in a vertical way ad works horizontally.
- A drill sleeve or quill that is a hollow rod surrounds the spindle. It is typically used to lower the drill vibration.
- A column that annular, solid, and rugged. It supports the drill sleeve or quill assembly and head.
- A Head of the drill machines holds the composition of the sleeve, spindle, motor, and feed mechanism. The head is gulped to the column.
- A worktable is supported on a section set to the column. The worktable can be adjusted according to the working height, direction.
- A base, which holds the entire drill machine, is quite similar to the worktable. When the machine is used for large mounting work, and that is quite unmanageable to support for the worktable. (Knowledge Reference – www.drilling-it.com)
Types of machines
- Portable machine: This is the hand-held machine that is movable to any workplaces easily. In automobile manufacturing, this machine is used widely. This machine fits 12mm to 18mm diameter of bits.
- Sensitive machine: This type of machine drills small holes for mainly electric works. The machine fits up to 15.5mm diameter of bits.
- Upright machines: It handles medium-sized works. It accommodates up to 50mm diameter of drills.
- Radial machines: It handles medium to hefty workpieces at a time. It has a heavy column bolted on a large, solid base.
- Gang Drill machine: This type of machine has a large base holding multiple drill machines mounted on different columns.
- Multiple Spindle machine: This kind of machine drills multiple holes at a time.
- Deep mole machine: This machine drills deeper holes than usual.
There are thus several types of Drilling machines structured according to variation of workload. Good knowledge about the variety and usage of the drill machines let a constructor execute work in due time, and intact.