Gains In Gundrilling


Gundrilling is a type of deep hole drilling that uses drills which allow a cutting fluid through to provide lubrication and remove chips as it’s working. Accuracy of the drill is only one advantage provided by this method. Because of the guide pads that are used, secondary finishing is often unnecessary. Gundrilling is also the best method for use of harder metals.
Gundrilling is used across many markets. For heat exchangers, boilers hydraulics, landing gear components, long drill tubes and other parts for downhole applications. It’s also used to drill out large propeller shafts to save weight.


7 Advantages of Choosing Gundrilling

1. Cuts a deep accurate hole in a single pass
2. Guide pads often cancel the need for finishing operations.
3. After initial machining, work hardening deforms either the piece or the
tool on each following pass. Therefore, age-hardened alloys must be machined
using a slower cut  with a hard tool so it’s done with the fewest number of passes.
4. Up to 6x faster than traditional drilling
5. High magnitude residual stresses can be measured with incremental DHD ¹
6. Highly efficient with low rate of error
7. Gun drilling machines allowing operators to closely monitor the drilling process.


At Double Eagle Alloys…

We specialize in gundrilling nickel alloys. Alloy 718 is a precipitation-hardening nickel-chromium alloy containing significant amounts of iron, columbium, and molybdenum, along with lesser amounts of aluminum and titanium. Alloy 718 maintains high strength and good ductility up to 1300°F (704°C). This alloy has relatively good weldability, formability, and excellent cryogenic properties compared to other precipitation hardening nickel alloys. The sluggish precipitation hardening response of this alloy allows it to be readily welded without hardening or cracking. Alloy K500 is a precipitation hardenable, nickel-copper-aluminum alloy that combines the excellent corrosion resistance of Alloy 400 with the added advantages of greater strength and hardness. The increased properties are obtained by adding aluminum and titanium to the nickel-copper base, and by heating under controlled conditions so that submicroscopic particles of Ni3 (Ti, Al) are precipitated throughout the matrix. The thermal processing used to affect precipitation is commonly called age hardening or aging.


Our internal gundrilling capabilities

Our in house Eldorado Model M75-30 Single T Base provides:
• Slide Stroke: 30” (762mm) nominal (26.5” actual without whip guides)
• Drill Capacity: 0.055”-0.750” (1.4-19.05mm) Dia. Hole

Whether you have a large custom order or individual pieces, let us help you get exactly what you need. We work with clients in industries around the world to fill their orders with the high standards they’ve come to expect from Double Eagle Alloys.



References: VEQTER Ltd – Deep Hole Drilling