Early September 2019 Boiler Update

The busy bees at Continental Fabricators have been making excellent progress on C&NW #1385’s new boiler. By late August work on staybolt installation was wrapping up. The next few photos show that work taking place.

The first shot is looking from inside the firebox at the firedoor ring and we can see the finished welding.

In this second picture we’re looking toward the front of the firebox at the crownsheet and rear tubesheet. The small group of staybolts not yet welded in are the flexible stays and the larger holes in the firebox sheets will accept the arch tubes. The arch tubes have a dual purpose in that they will form a structure to hold the arch brick in the firebox. They will also promote much better water circulation around the firebox while the locomotive is in operation.

This third shot shows the outside of the staybolts yet to be finished and with the boiler rotated on its side. We’re looking at the top of the vessel in the center of the picture.

This fourth picture is looking down through the steam dome inside the boiler at the braces welded in place to support the rear tubesheet. Those braces were discussed in an earlier update and this is a look at the finished product.

With the structural welding completed, as people across the nation were getting ready to fire up their grills for Labor Day weekend cookouts, the folks at Continental Fabricators were preparing a roast of their own. C&NW 1385’s boiler was moved inside Continental’s enormous heat treating oven for its Post Weld Heat Treatment (or PWHT). This process helps to relieve stresses built up during the welding process. The following two photos were taken while the boiler was cooling off after completing the heat treatment.

Next up, the boiler will get sandblasted and painted. The interior will receive Apexior paint which will help protect the steel from corrosion as it boils the water for steam.

Late July 2019 Boiler Progress

Welding and patience continues at Continental Fabricating as more stays are completed on the R-1 boiler.  No, the pictures are not upside down, that is merely the positioner at work to allow the greatest productivity and weld quality possible.  The steel forging which makes the base of the steam dome has been tack welded in place and you can see the welder’s feet as he makes the root and fill-in welding passes while he’s standing on the floor.

The other parts of the steam dome are being fitted together and the welding has been partially completed and soon will be done.  For the new boiler we have adopted a more European approach by having a removable steam dome.  This will make maintenance and inspection tasks much easier in the years to come.

Photos are courtesy of Continental Fabricators.

Early July 2019 Boiler Progress

Progress continues with the welding of staybolts at Continental Fabricating. The boiler is now mounted to the positioner and like a huge rotisserie it can be rotated to allow the welders to work from the best possible position and comfortable welders make for better welds.

In these pictures, the boiler’s fireman (left) side is down to allow for work on the top of the wrapper sheet without having to set up scaffolding or work from a ladder. This minimizes or eliminates fall hazards. From the firebox side this will allow work to continue without welding overhead so the workers aren’t standing under a shower of sparks as they weld.

The below photo inside the boiler is a unique perspective that won’t be available much longer. The steam dome has not yet been welded in place so this allowed Continental Fabricator’s Tom G. to position the camera right in the top of the boiler shell where we can see the water side of the crownsheet and the rows of staybolts that tie the crownsheet and wrapper sheet together. We can also see the rows of staybolts yet to come, many of which will be flexible stays.

C&NW #1385 boiler as of July 8, 2019. Photo courtesy Continental Fabricators.

Mid-June 2019 Boiler Progress

Chicago & North Western #1385’s boiler continues to see steady progress. Since the last update, the boiler has been moved across the Continental Fabricators shop floor and is now on the positioner.  With the boiler now on the positioner, it can be rotated to allow workers to put it into the best position for welding and assembly in areas that would otherwise be difficult to access.

C&NW #1385’s boiler on the positioner at Continental Fabricators. The positioner allows the boiler to be rotated. June 11, 2019. Photo courtesy Continental Fabricators.

Installation of the crown stays is also in process. Crown stays are the staybolts that connect the wrapper sheets – which wrap around the firebox – to the crown sheet (i.e. the top of the firebox). The crown sheet is directly above the fire and is the hottest part of the firebox.

crown sheet diagram

The crown stays (shown in green) support the crown sheet at the top of the firebox, preventing it from bowing inward from the immense pressures.

 

Late-May 2019 Boiler Progress

Work on Mid-Continent Railway Museum’s Chicago & North Western #1385 locomotive during the month of May has consisted of stay installation, stay installation, and more stay installation. With over 900 staybolts to be applied, this process represents one of the more time-intensive portions of the new boiler production. Each weld must be made with great care and precision to avoid leaks and ensure proper strength when the boiler is under operating pressure.

Continental Fabricator’s Tom G. peered into the belly of the beast on May 29th to take these photos of stay installation progress on the inside of 1385’s firebox.