Episode Summary:
The Biden Administration has quietly dropped a key sanction that both Democrats and Republicans have been using to block the completion of the Russia to Germany Nord Stream 2 gas pipeline. While the administration has announced that their opposition to the line continues, it’s scheduled to be completed by mid-summer.
Automotive Tier One major Mahle has developed a new type of electric traction motor for EV use, one that promises low cost, very high efficiency and critically, no expensive permanent magnets. The technology does away with slip rings or brushes using an AC inductive pickup to pass power to rotor mounted electromagnets.
Boeing has demonstrated the superiority of model-based engineering with a lightning fast 30-minute splice between fuselage sections on the new T–7A Red Hawk jet trainer. Dramatic improvements in build quality and assembly time suggest that match drilling and splicing may become as obsolete as dope and fabric.
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Transcript of this week's show:
Segment 1: With the colonial fuel pipeline shut down last week, focus has returned to the energy industry, and the Biden administration has quietly announced a very significant shift in policy: the company that’s building the big Nord Stream 2 project to pipe gas directly from Russia to Germany will no longer be subject to sanctions. The company, Switzerland-based Nord Stream 2 AG, is owned by the Russian energy giant Gasprom. The shift to significant, since it signals a change in the US approach to the gas megaproject, which bypasses the route through contested regions of the Ukraine and cements Russia as Europe’s major natural gas supplier. Under the Trump administration, sanctions against companies involved in the project were intended to stop the pipeline, in favour of US liquefied natural gas transported by ship to European ports. The Nord Stream 2 project is essentially a doubling of the original Nord Stream twin line, which at 760 miles in length is the longest subsea pipeline in the world. The project will double the original system capacity to 110 million m³ per year. Sources familiar with the matter reported by Axios.com state that with the line at 95% complete, the only way to stop the project would be to impose sanctions on the end user of the gas, Germany. The line is expected to be complete by mid-summer. Biden administration sources claim that the overall goal is still to prevent Russian gas shipments to Germany, but with the line complete and a considerable cost advantage compared to sea shipment of liquefied natural gas, it’s unclear what Washington can do to stop it.
Segment 2: The key enabling technologies for electric vehicles are of course, a battery, a motor, and electronics that control them both. Battery technology is generally regarded as the key to rapid adoption of electric vehicles, but motors are developing rapidly too. Auto parts Tier 1 supplier Mahle has developed a new type of electric motor that operates without magnets, a significant advantage given the projected worldwide shortage of the critical rare earths needed to make high-performance magnets. Electromagnets in electric motors is not a new idea, and AC induction motors have been used for over a century, but current EV technology using synchronous motors and permanent magnets are not only expensive, but heavy. The new Mahle development uses an excitation coil built into the rotor, but more significantly, sends the power to the rotating element not through brushes or slip rings, but using an inductive pickup. This contactless system in the new motor should have a service life similar to AC induction motors, with bearing wear being the primary limiting factor. The company claims 96% efficiency in a scalable design that can be applied vehicles from small passenger cars to heavy trucks. Electronics will be different from conventional motor technology, as AC power is needed for the inductive coupling, which must be rectified to DC inside the motor for the electromagnets. It’s unclear from the company where that AC comes from, but it’s certain to involve an inverter, then switch back to DC with a rectifier inside the motor itself. Eliminating brushes means converting the current from DC from the battery to AC for the coupling, then back to DC for the electromagnets. From an EV manufacture perspective, the other alternative for noncontact, no magnet drive motors are AC induction motors anyway, so the inverter assembly may be the better option, compared to expensive rare earth magnets.
Segment 3: Model based engineering is widely regarded as the future of product development from design to production, and Boeing has demonstrated the capability of this doctrine in a tough real-world application. The company has joined the front and rear fuselage sections of a Boeing/Saab T–7A Red Hawk military jet trainer with an alignment so close that the splice took less than 30 minutes. That’s 95% less time than conventional production, and with a higher quality joint. The aft fuselage sections are built by Saab in Linköping, Sweden, and are shipped to St. Louis for assembly to the Boeing built front section. This first airframe will be used as a static test article and will be followed by five engineering test aircraft ahead of the planned 351 aircraft U.S. Air Force order. The company reports a 98% reduction in drilling defects and an overall 50% improvement in production quality. Fuselage joins, or splices as they’re called in the industry are major cost in aircraft production and have become more critical since both Boeing and Airbus have developed heavily outsourced airframe programs with sections manufactured by multiple companies in multiple factories worldwide. The all-digital design of the Red Hawk has resulted in an 80% reduction in assembly hours, and a 50% reduction in software development and verification time. Will this be the end of shimming and match drilling on the line? Perhaps, but there is a hidden benefit to precise, repeatable large assemblies in production: they’re much more easily automated. We’ll be watching for robotic assembly to follow digital design in volume aircraft production.