According to this news report from CCN Business their might be an issue with some parts on the Boeing 737 Max not being heat treated; 

“Boeing on Sunday said some of its 737 planes, including many 737 Max aircraft, may have faulty parts on their wings. It’s the latest problem Boeing faces as it tries to get its most important and popular airplane, the grounded 737 Max, back in the air. Working with the Federal Aviation Administration, Boeing said it has reached out to airlines that fly 737 planes, advising them to inspect their slat track assemblies on Max and NG aircraft. The 737 NG series includes the 737-600, -700, -800 and -900 planes. Leading edge slats are an aerodynamic control surface that extend from the front of the wing. Some the tracks may not meet manufacturing standards and may need to be replaced, Boeing and the FAA said. They said if the parts are found to be defective, airlines should replace them before returning the planes to service.

The faulty parts could fail prematurely or crack. The FAA said a part failure would not bring down a plane, but it could damage an aircraft while in flight. Boeing has sent out a service bulletin and the FAA will issue an airworthiness directive requiring airlines to inspect and repair its slat track assemblies within 10 days. The company discovered the problem Friday, when Boeing was meeting with the parts supplier. Boeing employees noticed some of the parts were not heat treated, which led them to believe there might be a safety issue. The development comes as Boeing seeks to get the 737 Max back in the air. The plane was grounded worldwide after a fatal crash of an Ethiopian Airlines jet in March, which followed a fatal crash of a Lion Air jet in Indonesia in October.

Crash investigators have focused on an automatic safety feature on the jet as a possible contributor to the crashes. The newly discovered issue affects 148 slat tracks produced by a single supplier, Boeing said. The company said it believes 20 737 Max and 21 737 NG planes may have defective slat tracks. But the FAA advised airlines to check an additional 179 Max planes and 133 NGs to determine if their parts are also faulty. Of the group that needs to be inspected, 33 Max and 32 NG planes are in the United States. The company and the FAA said it has not been notified of any incidents related to the tracks on operating flights, and the fix should take a couple days to complete. “We are committed to supporting our customers in every way possible as they identify and replace these potentially non-conforming tracks,” said Kevin McAllister, CEO of Boeing Commercial Airplanes, in a statement.”

From world famous heat treat consultant David Pye we have this article about distortion in Hole Saws;

We were invited to consult for a manufacturer of hole drill saws to review the current problem of massive distortion and resulting scrap.

The state of production due to distortion of the hole cutter  was  as high as 75% scrap due to massive  distortion results after pressure quenching with nitrogen in a vacuum furnace,

The manufacturer was conducting the procedure in a 5 bar over pressure vacuum furnace

• Material review

The material was supplied in the unusual form of M2 High Speed Steel, friction welded to a low alloy steel for the support body of the completed hole saw. The material was also supplied in the coiled roll. The material test certificate was checked for composition, test (very simply) against the test cert information and found to conform to the test certificate.

• Hole saw manufacturing procedure

The steel roll cutting edge of M2 and Low carbon steel body were de-coiled and cropped to length.  Further the top plate was pressed out of low carbon steel and a hole drilled in the center of the punched plate.

Fig 1 Assembled and completed hole saw (Not representative of the hole saw under discussion in this article).

It was observed that when the coiled material was de-coiled and cropped to length, that the cropped piece always had a variation in the actual physical length of crop always had a variance of correct size and up to 0.125 inches.

This meant that the hole saw drill diameter was never actually constant. It further meant that after fold and seam weld. In addition to this, although the punched plate that is carrying the pilot drill bit was maintain its size, it was causing an undue stress in the assembled drill, prior to heat treatment.

• Current Heat Treatment Practice
• Load basket with approximately 100 assembled hole saws in ‘soldier fashion’.
• Load into vacuum furnace.
• Ramp up to the selected austenitizing temperature of 2250°
• Soak at temperature for 20 minutes.
• High pressure quench at 5 Bar over pressure with nitrogen as the quench medium.
• Air recirculation furnace at 1020°F
• Open furnace and inspect the load for distortion ovality.

Review and comments on the current heat treatment procedure.

It was established that the Isothermal Transformation Diagram for M2 had been considered, it was clear that the interpretation of the diagram was misunderstood.

It was also discovered by the writer that the understanding of the time necessary for transformation to the Ms line transformation was not considered (or recognized).

The next observation was, that the company did not understand the necessity for accurate austenitizing temperature. (Believing that the higher the temperature, the more uniform the metallurgy of the hole saw would be).

The writer conducted a Design Of Experiment to be used to establish to the client that although that the present heat treat procedure was incorrect, the hole saw manufacturing (crop, bending to form the OD, welding methods) were also influencing the distortion to the slight inaccurate differences on the crop to length.

A batch of 100 hole cutting saws were placed in the load basket for vacuum heat treat, after being measured accurately to note the influences of movement after treatment. Shown below is a comparative heat treatment

process program;

0riginal heat treatment                                      Suggested DOE process                                    

Load vacuum furnace                                                      Load vacuum furnace

Preheat by ramp up                                                         Preheat by ramp up

Selected austenitize temperature= 2350°F                1975°F

Soak time at temperature =20 minutes                      5 minutes

Over pressure N₂ gas quench=5bar (73.5psi)           Partial pressure 0.5bar

Remove the load basket from the furnace and check distortion occurrence.

On completion of the measurement comparison, it was seen that the percentage were as follows;

The original heat treatment procedure, from each batch of 100-hole saws an average of 75% scrap was observed in each load.

From the new recipe, the distortion was noted only in approximately 15% as scrap, the corporate management suggested that it was a ‘fluke’.

 

It was then decided to process a second and third batch of 100-hole saws. This was accomplished with almost the same result as the first alternative suggested new program.

 

 The new focus of evaluation was to ensure as near accurate fit up and to focus on the crop to length procedure.

This was accomplished and the newly suggested heat treatment program conducted once again.

 

The distortion factor improved once again and processed using the new heat treat program, which produced a scrap rate of   + – 5%.

Conclusion

The original program of heat treatment austenitizing temperature was too high to achieve the desired results

The second part of the program of pressure quenching was also too high. One has only to consult the TTT curve for M2, and it will be observed that the ‘nose of the cooling curve’ is far to the right of the transformation and time line at approximately 20 minutes to the Ms line.

Then the crop to length and manufacturing method tolerances were tightened up.

The company is now selling their products, better than ever.

Sincerely, David (Pye Metallurgic al International Consulting)

 

Back in February of this year we told you the story of auto parts supplier SISTEMAS AUTOMOTRICES DE Mexico installing a brand new pusher furnace line. Well the story is almost finished as the line is now ready for final acceptance and run off as you can see in the one photo below. To really complete the tale you can see the furnace arriving, being unloaded, installed and now pretty well complete. 

SISTEMAS AUTOMOTRICES DE Mexico Installs Pusher Line ​ While pusher lines are not a popular as they once were they certainly still have their place as we can see here. Transmission components manufacturer SISTEMAS AUTOMOTRICES has just completed the installation of a brand new 3 row pusher at their facility in Northern Mexico. The line was provided by AFC-Holcroft and MATTSA (their licensee in Mexico) in record time which  emphasizes the great partnership of both companies in the furnace business in the USMCA region. The first photo from SISTEMA shows the holding chamber and quench tank arriving, and the other two photos show the furnace being unloaded and subsequently installed.

It is seldom that we run across heat treat news items from Sweden but this makes the second within a week. Since we could only find one “Epiroc”photo to go with this item (showing one of their products) we widened our search to find another photo from the Swedish heat treating industry and seized upon the one below. This was taken 3 years ago at a Bodycote facility in Gothenburg and shows Gord Montgomery on the left, Harald Rothof KGO and two members of the Bodycote team;  “Epiroc has held a groundbreaking ceremony for its new heat treatment plant for rock drills at one of its global manufacturing hubs in Örebro, Sweden. With heat treatment an essential part of rock drill manufacturing, the top-modern plant – to be built through an expansion of the current workshop building – will further boost rock drill quality and performance, according to Epiroc. It will also lower customers’ total cost of ownership and enable higher production volumes, the company added. Helena Hedblom, Epiroc’s Senior Executive Vice President Mining and Infrastructure, said: “The investment is a key step toward ensuring that this first-class manufacturing site remains as productive and competitive as possible for the long term.” Production at the 1,400 m² heat treatment plant will be able to run 24 hours a day thanks to automation. It is expected to be up and running by late-2020. Energy efficiency is a key focus for the design of the plant, with, for example, residual heat recycled internally to heat buildings.”

There is a lot of blah, blah, blah stuff here but to a long story short this brand new facility will have high pressure vacuum furnaces which is what interests us;  “Oerlikon, a global provider of surface solutions, equipment, advanced materials and materials processing, is inaugurating a new $55 million Innovation Hub & Advanced Component Production facility in Huntersville, as part of its ongoing US growth strategy. The facility will serve as a cornerstone of Oerlikon’s additive manufacturing business in the US. The 125,000 square foot facility currently employs about 60 people and is fully functional. The additive manufacturing production facility is Oerlikon’s second location in North Carolina – the other site being a center that provides manmade fibers, in particular, carpet yarn systems. The new facility consists of R&D laboratories, a large-scale 3D printing area, CNC machining and high-pressure heat treatment facilities. The backbone of the plant consists of inert gas systems, chilled water systems, purified compressed air systems, as well as a tightly controlled temperature and humidity HVAC system.”

On June 5, controls company Super Systems Inc. (SSi) will be hosting a one-day training seminar in Mississauga, Ontario which talks about lots of heat treating “stuff” including NADCAP and CQI-9. SSi has been doing these events for years around North America with pretty good success. We will snap a couple of pictures during the event next week.

Kind of in passing last week we learned that gun manufacturer Kimber Manufacturing was closing down most or all of their production in Yonkers, NY and moving to Alabama. This story very much got our attention because it was not that long ago when we mentioned that fellow gun manufacturer Remington in Ilion, NY had also made the decision to move to Alabama. This lead us to do a bit of research and as it turns out these two companies are just the tip of the iceberg and join others such as Beretta and a whole slew of others which have made the decision to move from the Northern US to the Southern US for the reasons mentioned in this really excellent article from Larry Keane, Senior Vice President and General Counsel for the National Shooting Sports Foundation. Why this story is of interest to us is that virtually all of these companies has (had) an in house heat treating department and because this is firearms manufacturing you are looking at high end heat treating including Carburizing and both Gas and Plasma Nitriding. To give you an idea these photos show part of the in house heat treating department of gun manufacturer Glock.

“Georgia’s new Governor, Brian Kemp, may want to send New York Gov. Andrew Cuomo a thank you note and a bushel basket of peaches. That’s because another New York-based, firearms-related business has made the decision to expand its operations not in the Empire State with its highly restrictive gun control laws, but in this case in Georgia with its far friendlier business and political climate. Check-Mate Industries, based in West Babylon, N.Y., makes handgun and rifle magazines, among other firearms-related equipment as well as life-saving devices for the medical industry. The company is an original equipment manufacturer for firearms makers and the U.S. military. The diversified company describes its offerings this way, “Check-Mate Industries’ products are 100 percent designed, developed and manufactured in the United States. Since 1972, the company has operated as a tool & die, stampings and assemblies manufacturer.” Now, much of that production will take place in Thomasville, Georgia.

Remember The SAFE Act; In New York, Cuomo led the effort to outlaw standard-capacity magazines. In hurry-up lawmaking in Albany in early 2013 to pass his so-called SAFE Act, it was mandated that magazines could henceforth hold only seven rounds. Since magazines manufactured in that capacity are rare, to say the least, it was then decided that residents could own magazines capable of holding a maximum of 10 rounds, but they could no longer load them to full capacity. Larger capacity magazines were outlawed. Owning one of those could earn you jail time, although Niagara, Chautauqua and Erie County prosecutors now say they will not enforce that portion of the state statute. The SAFE Act also broadened the state’s definition of “assault rifle,” to include firearms with any “military-style” feature including telescoping stocks and flash suppressors. It also required every single modern sporting rifle to be registered with the state, be sold or moved out of state.

Others Went Before; Check-Mate is not the first New York-based firearms business that chose to expand someplace other than their home state. About a year ago, Yonkers-based Kimber Manufacturing, best known for its 1911-style pistols and classic sporting rifles, announced an expansion in Troy, Alabama, where it doubled production capacity. Remington Arms Company made the decision in 2014 to move production from its historic Ilion, N.Y. facility to a new factory in Huntsville, Ala. A move south is not necessarily the only more gun-friendly direction for a company to travel. Citing SAFE Act passage, Kahr Arms moved its headquarters from New York to Pike County, Penn. and subsequently opened an adjacent factory.

A Tale Of Two Capitals;  The difference in state capitals, government policies and political leadership could not be more striking. Even as Cuomo and his political allies in Albany keep finding new ways to pressure gun manufacturers, he has also vilified the NRA and expanded his assault on the Second Amendment, as Frank Miniter detailed last month. Former Georgia Gov. Nathan Deal, on the other hand, welcomed firearms manufacturers to Atlanta to speak with the state legislature about their concerns. On hand for one session were representatives from Glock, Daniel Defense, Honor Defense and Trulock Chokes, among others. Gov. Deal also announced last year that Taurus USA was breaking ground on a $22.5 million, 200,000 square-foot production facility bringing 300 jobs to the community of Bainbridge. Current Gov. Brian Kemp proudly campaigned and won election to succeed Gov. Deal on his defense of Georgians’ right to keep and bear arms.”