Bad solder joints cause of Russian Proton engine defects
The problem that has forced the Russians to recall all Proton second and third stage engines has been identified as the use of the wrong materials in solder joints.
According to specifications, the structural walls and the nozzle chamber of the gas generator had to be fused together with the help of the solder designated G70NKh, which employs nickel, chromium and manganese alloy (Ni-Cr-Mn). However the investigation revealed that due to mismanagement of the raw material usage at the Voronezh Mechanical Plant, the required alloy had been replaced with the PZhK-1000 solder comprised of palladium, nickel, chromium and silicon (Pd-Ni-Cr-Si). Because the replaced solder did not meet specifications, it could lead to structural disintegration of the nozzle head during the firing of the gas generator.
The discovery of the problem with the solder triggered inspection of other engines and revealed that all RD-0210 and RD-0212 engines from the second and third stages that had been manufactured during 2015 and 2016 had been equipped with defective gas generators. In order to re-certify these engines for flight, each of them would have to be disassembled, the gas generator would have to be removed and replaced, followed by the re-assembly and re-testing of each engine!
The article also notes that the next Angara rocket is also “unfit for flight” due to unspecified defects. It also notes widespread corruption and mismanagement throughout the Russian aerospace industry.
Sadly, the decision by the Putin administration to consolidate their industry into one huge corporation run by the government, and thus eliminate any competition, is only going to make solving this problem more difficult. What Russia needs is competition, with many different companies free to challenge each other for business. It also needs to allow companies to fail and go out of business.
Instead, everything is controlled from above, and thus no competition can happen. Rather than finding a new company to build these engines, the government is going to provide the company “economic aid” in order to modernize it. This is like putting a band-aid on a broken bone.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
The problem that has forced the Russians to recall all Proton second and third stage engines has been identified as the use of the wrong materials in solder joints.
According to specifications, the structural walls and the nozzle chamber of the gas generator had to be fused together with the help of the solder designated G70NKh, which employs nickel, chromium and manganese alloy (Ni-Cr-Mn). However the investigation revealed that due to mismanagement of the raw material usage at the Voronezh Mechanical Plant, the required alloy had been replaced with the PZhK-1000 solder comprised of palladium, nickel, chromium and silicon (Pd-Ni-Cr-Si). Because the replaced solder did not meet specifications, it could lead to structural disintegration of the nozzle head during the firing of the gas generator.
The discovery of the problem with the solder triggered inspection of other engines and revealed that all RD-0210 and RD-0212 engines from the second and third stages that had been manufactured during 2015 and 2016 had been equipped with defective gas generators. In order to re-certify these engines for flight, each of them would have to be disassembled, the gas generator would have to be removed and replaced, followed by the re-assembly and re-testing of each engine!
The article also notes that the next Angara rocket is also “unfit for flight” due to unspecified defects. It also notes widespread corruption and mismanagement throughout the Russian aerospace industry.
Sadly, the decision by the Putin administration to consolidate their industry into one huge corporation run by the government, and thus eliminate any competition, is only going to make solving this problem more difficult. What Russia needs is competition, with many different companies free to challenge each other for business. It also needs to allow companies to fail and go out of business.
Instead, everything is controlled from above, and thus no competition can happen. Rather than finding a new company to build these engines, the government is going to provide the company “economic aid” in order to modernize it. This is like putting a band-aid on a broken bone.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
Maybe you should send Mr Putin a copy of your paper.
The notion of soldering high temperature/pressure metal joints is a new on on this electrical engineer. A google search on G70NKh refers to the joining process as brazing and shows it is indeed used in this application.
Brazing is soldering. Neither process involves melting of the metal parts being joined – the defining characteristic of welding. Brazing typically involves higher temperatures and higher-melting point materials than soldering, but both involve using wicking forces to pull a molten joiner metal into the microscopic interstices between two unmelted metal components that each have higher melting points than the braze metal in use.
Mike Rowe Visits The Welding School, Jacksonville, FL.
https://youtu.be/dQ-LbUYZkcg
(10:23)
–oldest welding school in the US