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Published by Sigma Toolings | Precision Engineering Insights
How Sigma Tooled Up A 16 Cylinder Mining Engine Block. Zero Compromises.
A 16 cylinder engine block for the mining industry is not a simple machining project. It is one of the most difficult tooling applications in large component. Multiple operations across nine setups. Close tolerances on every operation. And a cycle time that cannot afford to miss.
When this project came to Sigma, the requirement was clear. To achieve the GD&T and cut time.
Cycle time proven as expected. Here is how it was done.
Why The 16 Cylinder Block Is Different
What made this project particularly complex was that long boring and long drilling had to be solved together. Boring was identified early as the main cycle time bottleneck. And the drilling required a specific three step process to ensure position accuracy through the full depth of each hole.
Both operations had close tolerance for error. A bore out of concentricity cannot be reworked. A hole drilled off position means a scrapped block. Every tool in the setup had to perform correctly on the first trial run.
The Tooling Sigma Engineered
Every tool for this project was specially designed for the specific requirements of this block. Nothing off the shelf. Nothing compromised.
For the boring operations, customised cutting edges were designed to achieve cycle time, concentricity, and surface finish simultaneously. Standard boring tools would have met one or two of these requirements. The customised tool design met all three at the required cycle time.
For the precision drilling, a three step process was designed to ensure accuracy through the full depth of each hole.
First, a spotface/counterbore operation was run before drilling. This creates a flat stable entry surface for the drill. Without it, any drill entering an uneven cast iron surface at the required position will deflect at the point of contact.
Second, a pilot U-drill was used to establish a precise reference hole before the long drill entered the component. The pilot guides the drill and reduces positional drift through the depth of the hole.
Third, an L/D 10 KRUZ drill was used for the blind hole application. This is a purpose built tool for high L/D applications where standard drills would deflect and produce off position holes.
This three step sequence is not a traditional process. It is the only reliable way to hold position accuracy on a deep blind hole in a large cast iron block at production volumes.
What The Result Looked Like
Cycle time was proven as per customer expectation. Concentricity was achieved across all bores. Surface finish met the required specification.
Every tool performed as designed on the first trial run. The customer confirmed the cycle time target was met.
This is what happens when tooling is designed for the specific application rather than adapted from a traditional process.
The Difference Between Buying Tools And Engineering A Solution
Most machining operations source tools from multiple suppliers. One supplier for the drills. Another for the boring bars. Another for the inserts. Each tool is optimised in isolation.
The result is a process where no single supplier takes responsibility for the overall cycle time and prove-out. When something goes wrong, troubleshooting begins. Every supplier points to the other.
When the entire tooling solution is designed as a system by one partner, something different happens. Milling and boring parameters, drilling sequences, and cutting geometries are all optimised together for the same application. The process is designed before the first chip is cut. And the cycle time is proven on the first trial.
That is the difference.
Is Your Project Ready For This Level Of Tooling?
If you are running a complex engine block or heavy component machining operation and struggling with cycle time, bore concentricity, or hole position accuracy, the answer is almost never a single tool change.
It is a complete tooling system designed for your specific application from the ground up.
We have tooled up cylinder blocks, transmission cases, axle housing and many more components. If your machining operation needs a complete tooling solution, not just individual tools, talk to a Sigma engineer.