Sophisticated drill technology

In 1898 Gühring produced the first HSS drills and remains true to its beginnings. Our variety of drilling tools is unparalleled in the market. The product range stretches from micro-precision drills Ø 0.05 mm to special solutions with Ø 180 mm and from HSS drills to solid carbide or PCD.


Innovative design for efficient cooling


A high chrome and nickel content in stainless steels ensures a high corrosion resistance and strength. However, the machinability of the material deteriorates at the same time – Process temperatures rise. The RT 100 Trigon® carbide drill, however, ensures high cutting speeds and feed rates – its innovative coolant duct geometry makes it possible.

Stainless high-grade steel such as V2A is applied for an increasing number of products and components. These steels excel especially thanks to a high content of alloying elements such as chrome and nickel. Examples for the application of V2A components can be found in the energy technology sector (i.e. heat exchanger components), the chemical industry, aircraft construction as well as in mechanical and automotive engineering.

The high content of alloying elements increases the difficulty in the machining of stainless high-grade steels. In addition, high cutting speeds and feed rates are required for economically efficient drilling operations. The result is high process temperatures during the drilling process especially in the high-alloyed steels as described. They put high demands on solid carbide drilling tools and ultimately accelerate tool wear.


RT 100 C – solid carbide drilling tools

CFD-simulation of flow behaviour in comparison:

Conventional coolant duct left and Trigon coolant duct design on the right in metres per second.

RT 100 Typ C – carbide drill

Developed as a special tool option of the RT 100 Trigon carbide series is RT 100 type C specially designed for long-chipping materials. It is available as a special tool ø 3 to 20 mm up to 7xD drilling depth. From ø 6.00 mm type C possesses the new Trigon coolant duct design.


RT 100 Trigon® drilling tools – new coolant duct design

Innovative cross-sectional coolant duct geometries were developed for these carbide drills in order to meet these requirements. The RT 100 Trigon® carbide drill is an innovative spiral-fluted drilling tool for the machining of stainless high-grade steel with patented coolant duct design for maximum performance.

The new coolant duct form, therefore, optimizes coolant volume, flow speed and flow direction and extreme process temperatures are perfectly dissipated. In comparison to conventional round coolant ducts, the cooling medium is specifically guided to the areas of the tool under the heaviest loads, the cutting tip and the cutting edge corners.

Advantages of the Trigon®  carbide drill coolant duct geometry:

  • Enlarging the coolant duct cross-section results in increasing the coolant volume and therefore improving the cooling of the tool.
  • Despite a larger coolant duct cross-section the stability of the tool is not negatively influenced, the drill cross-section available is optimally utilized.
  • Accelerating the flow speed in comparison to conventional, round coolant ducts along the cutting edges improves temperature dissipation.
  • Optimized guidance of the cooling medium to the area of the tool under the heaviest load at the cutting lips of the drill and the cutting edge corner area.

Micro-precision drills

Micro machining is constantly gaining importance in industries from mechanical engineering to electrical engineering. Here the drilling operation is the focal element. The smaller the components become the higher the demand for precision, consistent accuracy, and economic efficiency of the process. Mirco drill bits are the drills that help to perform these actions.


Solid carbide precision micro-precision drills


Gühring’s solid carbide micro-precision drill without coolant ducts cover a diameter range from 0.1 mm to 3.0 mm. Under stable machining conditions and with high-performance machines extremely good cutting parameters and long tool life can be achieved with solid carbide micro-precision drills. Amongst other things the application of ultra-fine carbide with the very high hardness displays an extreme wear resistance, makes the enormous performance capabilities of solid carbide micro-precision drills.

  • for stable machining conditions
  • increased cutting parameters and longer tool life

Application example:

Series production on a rotary transfer machine

Material: Heat-treatable steel 42CrMo4, with external cooling 10% soluble oil,

  • d = 1.2 mm
  • vc = 65 m/min
  • n = 17,242 rev./min
  • fn = 0.06 mm/rev.
  • vf = 1,035 mm/min

Solid carbide precision micro-precision drills


Gühring’s micro-precision drills in powder metallurgical HSS-E steel distinguish themselves by a very high wear resistance and a high toughness and cutting edge stability that is especially important under unstable machining conditions. The powder metallurgical manufactured HSS-E steel has a very homogeneous structure that has a positive effect on the consistently high-performance capabilities of micro-precision drills.

  • cutting process reliable under unstable machining conditions
  • wear resistant HSS-E-PM and high edge stability

Application example:

Series production on multi-spindle machines

Material for micro-precision drills: Stainless Steel 1.4301,

with external cooling, 10% soluble oil,

  • d = 2.0 mm
  • vc = 15 m/min
  • n = 2,387 rev./min
  • fn = 0.03 mm/rev.
  • vf = 71.61 mm/min

Solid carbide Exclusive Line micro-precision drills

also with internal cooling

Solid carbide ExlclusiveLine micro-precision drills, with or without IC, make the high-performance machining of most materials possible. With stable machine conditions and high machine performance, they can display their full performance capability. The 2-facet point grind per cutting edge with ground cutting edge honing permits high cutting values and an optimal chip break.

  • with stable machine conditions and high machine performance, i.e. in large batch series production
  • High-performance machining, especially in stainless steels and special alloys

Application example 1:

Series production

Material: Alloyed case hardened steel 16MnCr5, Internal cooling with 8% soluble oil,

  • d = 2.5 mm
  • vc = 120 m/min
  • n = 15,279 rev./min
  • fn = 0,.14 mm/rev.
  • vf = 2,139.06 mm/min

Application example 2:

Series production

Material: Stainless steel X6CrNiTi18 10, Internal cooling with 12% soluble oil:

  • d = 2.1 mm
  • vc = 60 m/min
  • n = 9,095 rev./min
  • fn = 0.03 mm/rev.
  • vf = 273 mm/min

Micro-precision drill types

Advantages and fields of application

Gühring provides the optimal solution for large batch series production with machine conditions with maximum performance and internal cooling as well as also for machining tasks with smaller batch sizes or with limited machine performance and difficult machining conditions.


Scope of programmer

Gühring’s comprehensive micro-precision drill programme of solid carbide and HSS-E-PM micro-precision drills covers the entire diameter range from 0.05 mm to 3.0 mm:


Gühring’s HSS/HSCO drills

Conventional, but absolutely essential. The HSS drills.

Carbide or HSS? The competences of tool materials are clearly defined – and carbide as the tool material for drilling tools has nowhere near been able to establish itself in all fields of application. Particularly with small and medium series production, with unstable machining conditions and always when toughness is required, users continue to rely on drilling tools in high-speed steel (HSS/HSCO). With an enormous product range and an extraordinary high manufacturing depth Gühring’s HSS/HSCO drills product range is unequaled worldwide.

  • Morse taper shank drills up to Ø 98.42 mm are also part of Gühring’s standard product range and are absolutely essential for large engine production, particularly in shipbuilding.
  • Standard extra length HSS drills with a flute length of 850 mm and a total length of 1000 mm with a diameter of 10 mm are for example applied in the mould, die and tool making industry.
  • HSS drills with internal cooling and with straight shank or with Morse taper shank for the machining of steel beams for example.
  • Furthermore, the standard HSS/HSCO drills range also includes twist drills to all current standards, centre drills, NC spotting drills, subland drills, and core drills.
  • Besides the standard range this product diversity especially also applies to the special tool sector. Here, Guhring can manufacture HSS/HSCO drilling tools with a diameter up to 105 mm for example. The various designs of HSS/HSCO drills are virtually unlimited.

Precision with solid drill geometry

New interchangeable inserts for the machining of steel beams and carbon steel

HT 800 drilling tool is suitable for the machining of steel, stainless steel, cast iron and aluminium. With various geometries and coatings the inserts are always perfectly adapted to the respective field of application.

Thus HT 800 drilling tools with optimised flute geometry achieves holes of the same quality as of a solid carbide drill. In combination with internal cooling the open flute ensures an optimal chip evacuation, especially out of deeper holes. As a programme extension Gühring now also provides interchangeable inserts for the machining of steel beams and carbon steel.

Steel beams for the most varying metal constructions are generally manufactured on special drill / saw machines. The clamping facilities on these machines are often unstable. That places particularly high demands on the drilling tools. The tool geometry must be designed to compensate for the unstable conditions and ensure a smooth drilling performance.

With a new carbide special drilling tool based on the modular tooling system HT 800 drilling tool WP Gühring provides an optimal tool for the machining of steel beams, it scores points with good centering characteristics and a smooth drilling performance.


The point geometry of the new interchangeable inserts for twist drills ensures optimal centering characteristics and therefore compensates for unstable machining conditions during the manufacture of steel beams. The large point angle in the outer area of the insert guarantees minimised burr development.

The interchangeable inserts for the machining of steel beams can be applied using all HT 800 twist drill standard holders 1xD, 1.5xD, 3xD, 5xD, 7xD and 10xD. The modular system enables a simple insert change directly on the machine.

HT 800 WP twist drill for the machining of carbon steel

Gühring has also extended its HT 800 twist drill program for the machining of carbon steels. The robustly shaped cutting a wedge of the special interchangeable inserts ensures high wear resistance without increasing the process forces. The concave-shaped cutting edge ensures an optimal chip break in long-chipping steels.

The interchangeable inserts for the twist drill have already been able to deliver remarkable results:

  • Market segment: Automotive
  • Component: Bush
  • Drilling depth: 24mm, through hole
  • Diameter: 19.5
  • Material: C40
  • Tool life quantity: 6000 holes
  • Tool life: 144 m
  • Cutting speed vc: 120 m/min
  • Feed rate per revolution f: 0.35 mm/rev.

HT 800 consists of a wear-resistant steel holder, an interchangeable cutting insert and a locking screw to provide the clamping requirement. Thanks to close-fitting tolerances of the insert pin and locating hole the insert has little play and is firmly positioned in the holder. The innovative clamping principle achieves maximum process reliability for holes up to 10 x D. The clamping screws with screw locking improve the grip even with operations subject to heavy vibrations.

Economically efficient and accurate up to diameter Ø 40 mm

With HT 800 Gühring has brought interchangeable insert technology to the market not only making highly accurate large diameter holes possible but also providing cost advantages. Advantages compared to conventional solid carbide drilling tools lie in the enormous machining flexibility thanks to the problem-free replacement of the different inserts depending on the machining of the material.

It stays clamped: Simple exchange on the machine

The HT 800 interchangeable inserts can be exchanged on the machine. The holder remains clamped. A tool change and the associated re-setting is not necessary. The result is an increase in process reliability and shorter set-up times. Machine downtime is drastically reduced.