Cummins Going Big On Dual Fuel
Cummins Inc. has announced plans to produce dual-fuel engines from 800 hp to 3500 hp (597 to 2610 kW) for high-horsepower markets. The first in the product portfolio, QSK50 Tier 2 for oil and gas well servicing applications, will begin production in midyear 2013, with other QSK Series engines to follow, including engines capable of meeting upcoming EPA Tier 4 Final emissions regulations, the company said.
Cummins high-horsepower dual-fuel engines will operate with common integrated controls which are designed to provide a seamless transition from diesel fuel to dual fuel operation. By default, an engine will run on diesel fuel until the operator selects the option on the control panel to run the engine on a blend of diesel and natural gas fuel. The engine will switch to dual-fuel mode and automatically select the substitution rate for the operator.
In traditional operating conditions, Cummins said a maximum substitution rate of diesel fuel with natural gas of 70% can be expected, with average substitution rates of greater than 50%, depending on application and duty cycle. The Cummins said its dual-fuel technology will be applicable to both new QSK family engines and available as a retrofit on existing QSK family engines in the field. Cummins global distribution network will handle upfit, commissioning and warranty on dual fuel solution engines.
Additional details and product introduction timelines by market will be shared in the coming months, the company said.
Also at the opening day of the Offshore Technology Conference in Houston, Cummins unveiled one of the first production QTR2500 transmissions, revealing a new, compact “V” design that the company said allows the transmission to fit into existing frac applications with minimal engineering change. Since announcing the launch of the QTR Series transmission program in the fourth quarter of 2010, the design has undergone refinement on the QTR2500 and QTR3000, driven by customer requirements. Production for the QTR2500 and QTR3000 will begin in the second half of this year.
With the QTR Series transmissions, Cummins said it is bringing technology commonly found in high-performance automotive transmissions to the pressure pumping market. Shifting is no longer a sequential set of events in time as while power is being transmitted through one layshaft, the next gear is preselected and engaged, waiting for the shift command on the opposite layshaft. Upon receiving the shift command, the transmission simply exchanges the clutch, resulting in a constant torque shift, Cummins said.