Intensive Spray Quench Tank

I did a lot of work while in school for professors and graduate students in the Metallurgical Engineering department in school. I would mostly help in the foundry, heat treatment lab, SEM/optical micrograph work and in the machine shop. I got bounced around between about 3 professors and 4 projects whenever they needed good help that could problem solve better than your average bear. I had recently proved my metallurgical processing mechanical aptitude to professors I worked for by getting a 100kw vacuum induction unit and vacuum arc melter working, they were about to throw both out. I also had just had refurbished the whole vacuum system on their vacuum induction melter system that was handed down from Oak Ridge at some point, that machine was a treat it had Atomic Energy Commission seals on it still and it frightened me a little. I shudder to think there was ever anything "hot" heated in that machine back in the days before saftey.

Here's the two vacuum induction units I worked on. You can see the back end of the Oak Ridge induction melter. I had the rougher pump factory refurbished and the diffusion pump was purchased new.

During my time as an undergraduate researcher there was one project that always seemed to fail to lunch, it made three graduate students quit in less than a year. The project was to design build and fabricate a intensive spray quench tank for the Navy to standardize the Navy C-Ring Test to evaluate suppliers performance. They wanted to see how hard it could be quenched and judge their pool of suppliers based off the work the graduate student would do. The problem was that they couldn't get a graduate student to fabricate/assemble the darn thing. So I was asked to get this working just like the two induction melters and the vacuum arc melter.

I worked with Dr. Mario Buchelli, a brilliant, industrious, Columbian, mechanical/controls PhD engineer with a passion for metals processing and mechanical metallurgy. He insisted you call him Mario, no formalities. He did the design work and I did the assembly and some light fabrication of the tank.

I was given the 20hp high flow, high pressure pump, 500 gallon tank, the header and a dubious poly acrylic lid for the tank. Everything else I had to figure out. I was told to get it working ASAP, I had <4 months before graduating. The goal was to be able to heat then intensively quench parts

Pictured above is the manifold.

This left:

• Hoses/piping for everything

• Flanges

• Saftey check valve

• Header manifolds

• Fixture to hold parts

• Fast acting 3 way pump capable of handling >100 gpm at 300 psi ($$$)

• 2 strainers for scale

• Heat treatment furnace

• Gantry for large parts

Designing and assembling it went really well, the worst part was probably finding a valve suited for our needs and moving positioning the tank and pump, both were heavy and awkward to move.

We also had to recondition the space and move equipment. The space we used previously housed the blacksmithing clubs pneumatic power hammer and tools. We moved those into the next room over but before we did that we had to scrap some really old hot isostatic presses that belonged to the ceramic engineering department, they were also incredibly heavy.

Once the space was prepared everything went smoothly. I assembled the tank and tested it for the first time. About the time it was near completed I heard about the ASM Student Research Competition that was gong to take place at the ASM Heat Treatment conference in Saint Louis in 2021. I talked to my professors about it and entered into the competition.

We needed an expirment though and determined that it would be nice to determine the quench severity of the quench tank. We decided to use 1045 as it had low hardenabilty so the case depth would have a noticeable change on the 2" bar we were spray quenching as compared to immersion quenching. Medium to low carbon steels are prime cannidates for intensive spray quenching too as the intention is to get a deeper case depth from a lower cost alloy.

We austenitized and quenched several bars at varying water temperatures and spray pressures. The bars were cross sectioned to make a one inch thick puck, we then surface ground and hardness tested it to determine the case depth. Here is a short video showing the process.

I finished the project before graduating but did not get a chance to process the data and I needed to make a poster to submit. Over my first summer working at Molycop I made the poster and presented it in Saint Louis at the ASM 2021 Heat Treatment conference. The contest was a two day event where the first day you presented your poster and second day you gave a ~7 minute presentation. I placed third and won a 500 dollar cash prize.