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  1. bobjustbob

    Carbon Equivalent of A105N Flange

    A .23% max carbon and 42CE is certainly not impossible. Our standard WCC/WCB and LCC/LCB would meet it. We had a customer that required a plain carbon steel with 85/55ksi tensile and these requirements for light rail. The customer was concerned about weldability. Some of the parts made up the...
  2. bobjustbob

    thread367-313448 hi Guys we

    ASTM A148 does not give a particular chemistry just some max P and S, unless it has changed since I last worked with it. What steel grade are you pouring? C, Mn, Ni, Cr and Mo would be helpful. What size test coupons are you cutting your samples from? I assume you are breaking standard .505...
  3. bobjustbob

    ultrasonic flaw defector for casting

    Due to the shapes involved in our castings and the difficulties using UT on a rough cast surface with irregular thicknesses and shapes we rarely employed it. Most commonly, for surface flaw detection, mag particle inspection either wet or dry for steel parts and dye penetrant for stainless. UT...
  4. bobjustbob

    Ferrous casting with porosity

    It is difficult to diagnose a "porosity" issue without a lot more information. There are many possible causes of the indications. The deox practice, pouring temperature, pouring speed, gating system, sand quality, etc.. Adding some machine stock is not an uncommon fix for some instances...
  5. bobjustbob

    Identifying a material grade based on PMI??

    How was the PMI performed? If it was done using an XRF analyzer then all you know is that it is a steel with about 1.10% Mn. It will not give you carbon, and that is the most important hardening element in any of these steels. There are methods that can give you carbon like using an OES. I...
  6. bobjustbob

    Identifying a material grade based on PMI??

    You cannot determine the grade with just a chemistry check. Depending on the method used for the PMI, you may not even get a full chemistry. What type of material (steel, iron, copper, etc.) is it? Bob
  7. bobjustbob

    ASME A216 WCB Stress Strain Curve

    Do you have one for ASTM A216 WCC? It will be the same. ASTM A27 grades 65/36, 70/36 or 70/40 would all be the same as well. All of those would be made with the same material and heat treated the same way. Bob
  8. bobjustbob

    Max. Limit to Harden a steel

    What do you mean by specified? If you mean per a material specification then sometimes. Some specifications have max hardness values that directly limit hardness. More often the hardness is limited by the ductility requirements of the particular grade. Is there a theoretical maximum hardness...
  9. bobjustbob

    Induction melting of AISI 321 mod

    I have not melted 321, but have made a lot of CFXX grades using stainless plate scrap. I doubt you will have a difficult time with your carbon, assuming you are not using a lot of 321H. I expect that titanium is going to be the tough part to keep in solution, especially when melting the chips...
  10. bobjustbob

    Heat Treating 4130

    As others have said, you will need to decrease your temper temperature. However, I don't know that I would have accepted a specification with those tensile requirements with a max hardness of 237HB. To get that 80ksi minimum yield strength, you are going to be at the top of your hardness...
  11. bobjustbob

    Most efficient and fastest way to melt down metals in medium scale foundry?

    There is no way you are getting to 3000°C. You are not getting to 3000°F in a backyard foundry. Bob
  12. bobjustbob

    MONEL BODY X MONEL DISK X MONEL BODY - DIFFICULT TO GET GOOD WELD PENETRATION DEPTH

    What grade of monel are you talking about. We made quite a bit of M35-1. Each heat required a weldability test per the supplementary requirement S-22 in A-494. Bob
  13. bobjustbob

    Duplex steel production in induction furnaces

    Ed, How do you add the nitrogen bearing Chrome? We would generally add it after the first check of the nitrogen, none typically in the charge. We would get the bath hotter than we would typically for a stainless and add it in. We would get lots of slag but generally good pickup. It worked that...
  14. bobjustbob

    Duplex steel production in induction furnaces

    I don't know what you mean by "clean the furnace with bottom-dipping argon." Before we would melt a CD3MN heat, we would melt a heat of stainless (CF3M or similar) and make sure that the furnace cleans out well. I don't know what you mean by "measure the nitrogen in the mine." You can measure...
  15. bobjustbob

    How to produce Duplex ss by induction furnace and its improvements.

    Your chemistry looks fine. I would reduce the Mn by half for mechanical properties but that should not be causing a gas issue. Your nitrogen is fine, is that checked by combustion analysis (LECO)? Have you produced any heats without the argon purge? For this material you should not need an...
  16. bobjustbob

    How to produce Duplex ss by induction furnace and its improvements.

    Do you add anything into the ladle for deoxidization? I am not talking about degassing with argon. Tell me more about the argon purge in the ladle. It sounds like you have a lance pipe in the ladle as the heat is being tapped out of the furnace. Is this correct? You state that your scrap has...
  17. bobjustbob

    Price difference between Impact tested steel and non tested steel

    Like all the other answers, it depends. To perform the impact testing is not that expensive, for normal temperatures. Testing stainless at -321F is going to me move expensive than a -50F LCC requirement. It has been 10+ years since I sent any to an outside lab but it was about $150 at the time...
  18. bobjustbob

    How to produce Duplex ss by induction furnace and its improvements.

    You should not need to argon purge CD3MN. We poured CD3MN regularly out of a 2000lb and 4000lb induction furnace. What kind of ladle are you using? New or used and how is it treated before tapping? What are you use for ladle additions? I don't remember having any issues with cracking in...
  19. bobjustbob

    IBR Approved Forge or Foundry in Europe

    I worked in a foundry in the US that was a "Well Known Foundry" under IBR. A foundry does not require this status in order to make part for IBR service. We made valve castings for a few years to their requirements before getting the "Well Known" status. I hope it has changed but when I was...
  20. bobjustbob

    Why measure Hardness in addition to Strength?

    I am going to check the hardness on my batch regardless of if it is in the material spec or not. In some cases I check as quenched hardness prior to temper as in in process quality check. I can do that out on the floor as soon as the parts are cool. The tensile bars need to be processed by the...
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