Gun drilling process is used to produce deep and straight holes. This process is very specialised as compared to the conventional twist drilling process. The standard gun drill tool geometry has a single effective cutting edge. Unlike the twist drill the gun drill cuts through the metal eccentrically and once inside the component the tool self-pilots itself. The hole is further burnished due to the guide pads which finally results in a precise round hole with maintained straightness. The Coolant enters the tool through the coolant through hole and the chips are gushed out through the V shaped profile on the gun drill. Gun Drilling is effective from ф1 to ф30, but if you wish to go higher, BTA drilling becomes more effective than gun drilling.

Gundrilling, one of the basic and frequently performed material removal processes in the automotive, die and mold, and turbine industries, is becoming increasingly more complex, demanding, and experiences an unprecedented growth. Inspite of significant increase in the demand for economically producing holes and forprocess reliability, gundrilling and gundrill manufacture are still considered an esotericart, and there still exists a lackof knowledge on the exact relationships between the point geometry, the grinding process parameters, and the process mechanics, resulting inmany methods for drill production and, consequently, in wide variations in process performance.

Go to our Gun Drill Machines

Trepanning is a special operation mainly used on when conventional machines are tooled up to do deep hole drilling. Usually in such cases the machine power is less and hence Solid BTA drilling is not possible.  Trepanning is also used when a solid core is required. The trepanning operation is performed on a blank workpiece without any holes. The Tool geometry allows cutting only on the circular section whereas a solid core is left in the middle. This core can later be extracted for use. Typically only through hole applications are advisable with Trepanning since the core extraction can become troublesome in case of a blind hole. The tool covers a large range of diameters upto 500mm. There are limitations to the lower level of diameter that can be achieved with this process due to the geometry of the tool.

Go to our Trepanning and Boring/Drilling Machines

Skiving is a hole finishing process used when very tight dimensional and geometrical tolerances are required. It is the fastest method to achieve surface finish having very fine peaks and valleys ideal for roller burnishing process. The Skiving Tool is basically a twin/multiple edge floating reamer which follows the existing bore. The Roller burnishing tool coldworks the surface by merging peaks & valleys thereby producing very high surface finish and also a hardened surface. Both Skiving and Roller burnishing processes can be done simultaneously by using combined Skiving cum Roller Burnishing Tool. This process is 8 – 10 times faster than honing operation. The Skiving blades and burnishing rollers are expanded hydraulically while rotating and feeding though the bore. At the end of the operation these are retracted and the tool is withdrawn. High pressure coolant is supplied to the tool through the annular area between the bore and the tube outer diameter. The coolant along with the chips is evacuated from the other side.
Profimach offers dedicated Skiving & Burnishing machines for high production scenarios. This setup can be accommodated in a BTA drilling machine.

Goto our SRB - Skiving Roller Burnishing Machines

Counter Boring operation basically enlarges a pre-drilled bore. Usually counter boring is used when machine power does not allow solid drilling of that size.It covers a large range of diameters up to 500mm. The number of cutting edges on the tool can vary depending upon the amount of stock removal. As the counter bore tool enters the component, the pads are supported by the finished bore diameter. The Coolant and chips flow is similar to BTA drilling operation or chip forward.

Goto our BTA Drilling Boring Machines for Counterboring

Pull boring is being used mainly to have very straight and accurate long holes. The oil is fed similar to BTA drilling or counter boring i.e. through the pressure head. This has guide pads which are supported in the pre-bore, thus producing the enlarged bore on the original axis.

Got to our BTA boring-Drilling Machines for Pull Boring

Pull reaming is used to improve straightness and accuracy of long holes. The reaming tool is rotated and pulled through the drilled hole. The surface finish as well as size of drilled hole is improved using this process.  Profimach provides reliable, well designed machines for this process that are guaranteed to perform.

Goto our BTA machines for Pull Reaming