Caterpillar marine engines Tier III, a consolidated reality, which now concerns Caterpillar’s full line for commercial applications and yachts (Baglietto Shipyards, for instance) as well.
Caterpillar marine engines Tier III. Listening the words of Ryan Darnell
For instance, both 3516E and C32 Diesel engines use SCR to get the emissions rules compliance. Ryan Darnell, Marine Product Value engineer within Caterpillar’s Large Power Systems Division says: «What’s not so widely acknowledged is that SCR delivers the lowest total cost of ownership in the marine sector. One of the main reasons why is because the relationship between engine-out NOx and fuel consumption is inversely proportional; this means SCR maximizes engine efficiency. The amount of diesel fuel required to run a Tier 4 Final engine from Caterpillar with an SCR can be up to 9% lower than that required for a Tier 2 or Tier 3».
SCR compared to EGR
Comparing SCR with EGR, Darnell said: «while the approach may promise compliance, it depends on complex interactions of mechanical, electrical, and fluid processes working together in perfect unison» and that «The SCR option is not about redesigning the engine. Meeting Tier 4 Final using solely EGR has implications for engine efficiency and durability. Dramatic technological countermeasures can soften the impacts, but not eliminate them. The EGR option cannot claim validation in the harsh environments that engines face in marine applications. We’re very comfortable that we have not developed our Tier 4 Final marine solution around a technology that’s untried in its market which could compromise customer uptime».
The naval architects’ feedback
«The feedback we got from naval architects on this one was ‘make it as flexible to install as possible’, and that has been our guiding principle. The Caterpillar marine solution is also the most efficient SCR system on the market due to achieved lower overall fluid and fuel consumption for improved TCO, minimal new engine content for greater reliability and establishment of common designs and processes across the platform which reduces variability».
C32, 3500E, C280
The final statements of Ryan Darnell concern «EPA Tier 4 Final-compliant C32, 3500E, and C280 series marine engines are being offered with SCR because this technology offers not only compliance, but ease of installation, increased performance, and the lowest TCO. As a company, Caterpillar has advanced competencies in both SCR and EGR technologies; our position is based on selecting the right technology for the applications.»