The transition to Tier 4 engine technologies is prompting major changes in engine technologies. But it is also triggering significant modifications in the way Caterpillar designs its engines.
The U.S. EPA regulations that begin to take effect next year significantly reduce emissions levels, forcing engineers to employ a number of new combustion and aftertreatment solutions. For engine suppliers such as Cat’s Industrial Power System Division (IPSD) and many of the equipment makers that use its engines, the regulations mark an unheralded level of change.
“Customers must start [incorporating] engines early. It’s a huge change from Tier 3, probably the biggest change we’ve ever seen,” said Pete Brown, New Product Introduction Manager for Cat IPSD.
Meeting these requirements required a more finely controlled design process. “We’ve revitalized our operations with a very structured approach,” said Brown.
Cat implemented a corporate-wide process that is the same in all its facilities, with identical steps, review cycles, and measurement criterion, he explained. A key aspect of the design is to include more groups in the planning phase and throughout the design cycle.
These team members now represent most of the groups related to the full product life cycle. More groups are involved, and most begin their involvement at an earlier stage in the design cycle.
“Concurrent product process and design used to mean designers and suppliers, now it means everyone,” said Brown. “Product support used to come in late in the cycle. Now we bring them in very early.”
The manufacturing groups also provide input from early on in the cycle. These production teams are no longer limited to Cat’s internal groups. Its OEM customers will often put different engines in various models.
As aftertreatment becomes more critical, this is no longer simple. Engines and aftertreatment equipment are becoming more tightly coupled, so it is mandatory that they be installed as a complete system.
“In final assembly, we have to be sure the engine gets married to the right aftertreatment system, whether it’s done at our factory or in the field,” said Terry Goff, Director of Emission Regulations and Conformance at Cat IPSD.
The design cycles for Tier 4 engines are fairly long. These steps are also more tightly coupled than in the past.
The post-production analysis of the Tier 3 engine marked the kickoff to the Tier 4 efforts. Cat is currently in the concept stage for evaluating Tier 4 Final designs, exploring the pros and cons of different approaches. Tier 4 interim is in the prototype stage, Brown said.
Brown also noted that Tier 4 requirements extend even to fuel providers. Equipment vendors need to understand that new fuel will be needed so they can alert their customers and possibly even enter discussions with diesel fuel providers.
“Many of our customers don’t know the intricacies of Tier 4. We explain aspects like the need for low sulfur fuel,” he said.