Trepanning

Trepanning produces larger diameter, deep drilled holes, which leaves the core intact.

Trepanning is a precision machining method that produces larger diameter, deep drilled holes, and which is more cost effective than typical gundrilling techniques.

Unlike gundrilling, trepanning leaves a core from the center of the drilled barstock instead of reducing it to chips, and can be best described as core drilling.

Since trepanning leaves the center solid core of the tube intact for testing, reclamation or reuse in another project, this process is ideal for very expensive materials and alloys, and in instances where your component requires post-processing testing. The nuclear industry, for example, frequently relies on trepanned core materials because they can easily be tested for critical performance and safety specifications and considerations, and archived for later evaluation.

Trepanning produces larger diameter, deep drilled holes, which leaves the core intact. | Dearborn, Inc.
Trepanning produces larger diameter, deep drilled holes, which leaves the core intact. | Dearborn, Inc.

Our trepanning capabilities allow us to provide the following:

  • A core approximately 1.00” to 1.50” smaller than the bore of the part that is trepanned which can be used to produce additional parts, potentially decreasing your downstream material costs
  • Smallest trepan size available is a 1.375” diameter bore leaving a solid .375” diameter core
  • Largest trepan size available is 6.00” diameter bore leaving a 4.50” diameter solid core
  • Maximum part length able to be trepanned is 32’
  • Trepanning is typically utilized for less precise drilling requirements and when further machining is required
  • Materials that we trepan regularly include Inconel®, titanium, Hastelloy®, heat treated stainless steel, beryllium, aluminum, brass, plastics and composites, copper, etc.