Heavy Industry: Critical Design Variation

Heavy industry leaders rely on Sigmetrix’ tolerance analysis and GD&T software solutions to work on complex surfaces to obtain unique critical design information not otherwise available. Whether it’s the intricacies of a truck engine, the assembly of a tractor cab, or the fit and finish of an instrument panel, engineers and designers depend on our technology to add robustness to their designs and improve product performance while increasing revenues and decreasing costs.



APPLICATION -Heavy Industries Truck Engine, Design Variations Solution

Objective: CETOL 6σ used to solve analyze a complex problem in the engine’s design – to determine the sensitivity of a variety of dimensions, including valve train analysis, head assembly and piston assembly.

Results: Analysis determined valve clearance design variation on the engine. Half of the dimensions on the top 30 were more sensitive than previously thought. Based on the study, the customer increased the engine’s efficiency and boosted performance.

APPLICATION – Welded Assemblies, Fit & Alignment Variation Solutions

Objective: To gather sensitivity and contribution information necessary to focus on critical features for engineering analysis.

Results: CETOL 6σ used to understand fit and alignment. Determined welding fixture error. Improvement in assembly and manufacturing process resulted; reduced assembly time and warranty costs.


Objective: Cab door works similar to a car door, with a latch on the door that locks onto a pin attached to the cab frame. Misalignment of the pin and latch causes the latch to malfunction causing the door to not stay closed. Multiple components require many engineering hours to evaluate.


Results: Sigmetrix’ solutions determined issue and solved problem in matter of weeks; reduced engineering assessment time by three months and saved the customer over half a million dollars.

APPLICATION – Roller Bearings, Tolerance Analysis Solutions

Objective: Large bearing was stacked in set of five; used to control variation of oil drill shafts. Contact area was not being controlled properly and there was too much load on a single bearing set. A small  design variation resulted in inconsistent loads, causing drill failure.

Results: CETOL 6σ was used to perform an analysis that showed the sensitivity of a certain bearing needed adjustment – resulting in a design change.