Steel Exposed to High Temperature for Short Term
Steel Exposed to High Temperature for Short Term
(OP)
I am reviewing a 1/2" diameter steel flatbar hook. It is used to drop another material into an oven, and thus is exposed to 1500 degrees fahrenheit for a quick second. My question is if anyone can point me in the direction of some resources which will give me an indication of how this heat exposure will effect the steel over time, what kind of stress the steel will face from this very short exposure, etc..
Thanks
Thanks






RE: Steel Exposed to High Temperature for Short Term
i'd wonder how hot the hook actually gets, exposed for such a short time.
there's data in Mil Hdbk 5 (or MMPDS-01), both available online, but for exposure to 1/2hr.
if anything, i'd suspect that might just be a thermal fatigue thing happening, but i don't think so ...
Quando Omni Flunkus Moritati
RE: Steel Exposed to High Temperature for Short Term
If you want to be safe use the full temperature of 1500 farenheit which would correspond to about 80% reduction in your yield strength.
RE: Steel Exposed to High Temperature for Short Term
What is a “1/2" diameter steel flatbar hook”? And, are you loading a heat treating oven, or some such, where the hook isn’t exposed to the 1500̊F temp. for an extended period of time? What is its temp. after many cycles? You can usually take steel up to 600 - 700̊F without appreciably changing its Fy or Fult.; its modulus of elasticity will be about 90 - 85% at those same temps. As long as you can keep its core temp. in the 600̊ range, or less, you should be o.k. The biggest thing I would expect in working in that hot environment would be accelerated scaling and loss of net section over time. People who work their equipment at these temps. use much higher factors of safety to account for these things, and then inspect it regularly.
RE: Steel Exposed to High Temperature for Short Term
I'm just looking for direction to a resource which can give an indication of the effect (on strength mostly) of very short term exposure to such temperatures, over time (many cycles). The hook is also carrying ~600 lbs (dropping that load into the 1500 degree oven).
For a very short exposure to that heat, an 80% reduction in yield strength seems pretty severe..
Thanks for the responses
RE: Steel Exposed to High Temperature for Short Term
RE: Steel Exposed to High Temperature for Short Term
you can do a bunch of thermodynamic modelling to figure it out, or you can paste a bunch of thermocouples (or heat sensitive paint) on the hook. or maybe there's some sort of viewing aparatus that detects surface temperature ? i'd've thought that the hottest location would be the ingot (?) contact area.
are you trying to figure out if the hook'll break ?
Quando Omni Flunkus Moritati
RE: Steel Exposed to High Temperature for Short Term
Dik
RE: Steel Exposed to High Temperature for Short Term
but i've got to ask "what's the value of the hook ?" it's a simple 1/2" barstock. if there's a question about how much load can it pull, try it out ... you might want to have a larger hook standing by if you have to pull a load from the oven (you wouldn't want to spoil a load 'cause of the hook breaking).
maybe it's a question from OH&S ? so now the value of the work isn't the value of the hook, and you Have to get a number (guessing is not an option !?)
Quando Omni Flunkus Moritati
RE: Steel Exposed to High Temperature for Short Term
BA