Digging Deeper - August 2022 - Akkerman

Digging Deeper – August 2022

Akkerman Inc.

Digging Deeper – August 2022

Tunnel Boring Machine Cutter Head Selection – A Manufacturer’s Perspective

A tunneling project consists of numerous intertwined puzzle pieces. Often, the cutter head on the tunnel boring machine is the most critical. It is the front line to progress. Without a properly designed cutter head, production can be slow or nonexistent.

The cutter head design and its tooling are dictated by the anticipated ground conditions on the project. The best results come from a cutter head design that is specific to the project’s ground conditions.

Deciding where the cutter head tooling should fall on that spectrum requires some considerations:

  • How long is the drive?
  • How hard is the ground?
  • Is the ground abrasive?
  • Will you be able to dig up the machine if you encounter an obstruction or need to replace tooling?
  • What will it take to replace tooling underground?
  • Is it possible to replace the tooling underground?

A good geotechnical report can answer many of these questions.

Tunneling Ground Conditions

Ground conditions can vary significantly from one project to the next and even every few feet along the same alignment. For now, let’s focus on some of the most common ground types experienced when tunneling – sand and gravels, clay, mixed ground and rock.

Each ground condition requires different cutter head tooling to be successful, and when appropriately selected, can significantly mitigate risk. Soft ground cutter head tooling typically includes cutter teeth, cutter bits, and scrapers. When hard ground or rock is expected, cutter discs are used. Mixed ground cutter heads blend the soft ground and hard ground tooling and are required when softer materials surround cobble or boulders.

The most reliable tooling usually costs the most, but there is peace of mind knowing that the cutter head will handle it if something unexpected is encountered while mining.


Filming Onsite

This rowdy gang torched up several tons of scrap steel in the outside lot to remain quiet while the film crew was onsite. In Jared’s words, “You wouldn’t want to run into this bunch on the streets!” Absent from the gang photo is Josh Therring, who was on vacation.


15th Akkiversary

Nathan Lindeman

Nathan Lindeman began at Akkerman on August 1, 2007, as Design Engineer and is currently a Senior Project Engineer.

Nathan has made significant contributions to all of Akkerman’s product lines, though he often takes the lead on GBM design work and hydraulic system design. Lately, Nathan has been focusing on engineering GBM sales order items, an EX50 redesign, and TBM/5200 hydraulic updates. Most recently, Nathan has taken over Engineering design activities related to the Sliplining product line.

Nathan earned his B.S. in Automotive Engineering Technology from Minnesota State University, Mankato, in 2001.

He was first employed by Arctic Cat of Thief River Falls, WI for five years as calibration engineer, conducting fuel injection, engine performance, and system engine package development for snowmobiles. He also spent one year employed by S&S Cycle, which specializes in performance engines and accessories for American motorcycles in Viola, WI doing similar work.

At home, Nathan likes to work on and ride motorcycles. He’s also restoring a 1990 Jeep Wrangler with his son.

When reflecting on what he enjoys most in his position, he states, “I enjoy the challenges that come with each new design. Our machines are really impressive! The people here are great to work with.”

Brad comments, “Nathan is one of Akkerman’s most innovative, creative, and resourceful engineers, and I am grateful to have him on our team. Nathan is also persevering – if something doesn’t work out, he goes right back to the drawing board to find another solution.”

When you see Nathan, congratulate him on joining the ranks of the 15-year club and share a favorite memory with


Staff Highlight

Lamont Andrews

Lamont began employment on 9/22/97 and will join his colleagues in the 25-year club next month! Lamont spends much of his time on the road, tackling one customer project after another. Lamont’s dedication and willingness to help our customers become successful make him very deserving of this honor.

Nominated Because:

“I nominate Lamont Andrews for his continued dedication to our customers. Lamont is dependable, knowledgeable and a true road warrior of Akkerman.”

“Lamont is an essential component of technical support services at Akkerman.”

“I appreciate Lamont’s willingness to help educate our customers through YouTube videos.”

Admirable Qualities:

  • Dependable
  • Knowedgeable
  • Hard-Working
  • Road Warrior