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For the older guys...steel quality..???

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  • For the older guys...steel quality..???

    I'm still shaking my head.
    Working with steel from all over the world it seems.
    Latest...the china tubing for gates I've been using. Horrid crap. The galvanized coating is almost like someone slopped it on with a sponge.
    Really thick in spots...almost nothing in others.
    The other day they dropped off a new batch.
    Made in Malaysia. Unbelievable how much better quality. Makes it a whole new game when you have consistant thickness and od size. The coating is near perfect which makes welding it far easier...no suprises!
    That got me wondering...
    Back in the day...I'm betting there where serious issues with North American made steel also.
    That had to improve somewhere along the line.
    But when?
    And was there a time when we had the "Best of the best"?
    Is metallurgy and sizing the best it's ever been as far as US or Canadian made steels?
    Or has cost cutting degraded that also?
    I used to use Canadian made DOM tubing to build race car cages. The stuff was unreal quality. Every stick was identical. Beautiful stuff to work with.
    I'm wondering what is out there now??
    But... Malaysia???? I had no idea...
    Russ
    I have tools I don't even know I own...

  • #2
    I remember in Edmonchuck in the 70s we always got Canadian steel and never had any problems, then we got some offshore 4" plate and it was full of layers and laminations so that when flame cutting the cut would start to go through, hit a lamination and shoot off at any weird angle it pleased. Couldn't use it and sent it back and got some Canuck plate. Peter
    The difficult done right away. the impossible takes a little time.

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    • #3
      I was bandsawing a piece of what was supposed to be 1018 steel(customer supplied) the other day and all of a sudden I hit a hard spot and a bunch of teeth got ripped off the blade I had heard of that happening but that was a first for me.

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      • #4
        I think that steel product quality is a pretty strong function of the age of the equipment that is used to make it. That, combined with how hard you push the capacity limits of the equipment.
        Example: your galvanized tube. In a perfect world, hot galvanized tube will be created by dipping it in a tank of molten zinc, after first being pickled to get it clean. Whether the tubes are sealed for outside coating only is another issue. The coating is rated by grams of zinc per square centimeter or similar, and this is determined by how long the tube is in the tank. That is, if someone doesnt try to increase output by loading too many tubes at a time. This will cool the tank and the zinc layer will will be both thicker and more variable. You end up with more product throughput, but rather poorer quality, and you wasted zinc, (but that is bought by another guy.)
        Consider an electric furnace feeding on scrap plus alloying additives. The general drill is: charge the crucible with a couple of hundred tons of scrap, strike the arcs, and in about twenty minutes a sample to the auto analyser will tell you how long to blow oxygen and how much of whatever to add as alloying agents. You then add the ingredients, blow the mix, and pour into the continuous caster. Maybe you are in a hurry, or "the push is on" and to save a LITTLE time you shorten the blow by a minute. On an average furnace cycle of less than an hour, that will incease plant throughput by twenty to thirty minutes a day, EVERY DAY, and who will notice? BUT there are probably three or four of those furnaces feeding the caster, and you manage to add 200 tons of off-spec steel to the plate line or the wire mill or wherever. That is a lot of 1/4" plate! And a mill like I described is only about nine million tons/year, and I will bet that there are lots of bigger ones than that. I dont think it is a deliberate conspireacy, just the reality of "go, go ,go."
        Duffy, Gatineau, Quebec

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        • #5
          We were building some pressure vessels at work a few weeks back and some of the fittings were made in China. We had a particularily hard time to get one fitting to stop leaking. When the tssa inspector came to check the vessels , he noticed the offshore fittings and told the shop foreman that if those fittings were used again he would not issue a passing grade for the vessels. I think he must have had an unpleasant experience with them before. To make matters more interesting ,the inspector was Chinese.

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          • #6
            The quality of 1018 & 12L14 round bar has been awful for several years.

            Can you guess where it's made?????

            Hint: it's made in a country whose name ends in "A". But, maybe not the one you think.

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            • #7
              Worst quality comes from the USA....... as well as china.

              bean counters here, who knows. there.

              Got some chinese plumbing fittings, elbows joiners, a faucet or two....... They leaked. They leaked no matter what. They leaked at any pressure. They leaked no matter how much dope you used.

              Some USA ones did just the same, in a slightly different way.

              Got some more, came from someplace crazy like Pakistan or Turkey.... worked perfectly.
              1601

              Keep eye on ball.
              Hashim Khan

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              • #8
                Had trouble with new water heater joints leaking, tried everything including about 1/16" teflon tape, which squeezed out after about a week. What finally worked and lasted 5-6 years now was Permatex #2. Had to let it set up for a day though.
                mark costello-Low speed steel

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                • #9
                  I think we Yanks tend to be full of ourselves. In the global economy of today's world we're not special, and if Europe hadn't tried twice in the last century to bomb themselves into the stone age they would have been our fierce competitors for much of that century. That would have taken some of the gilding off our self-absorbtion.

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                  • #10
                    Or if they hadn't, possibly they also would be using 120 year old steel plants (as we did until recently).

                    being bombed does force one to upgrade....... Not an optimal solution, but remarkably effective.
                    1601

                    Keep eye on ball.
                    Hashim Khan

                    Comment


                    • #11
                      Originally posted by J Tiers
                      Or if they hadn't, possibly they also would be using 120 year old steel plants (as we did until recently).

                      being bombed does force one to upgrade.......
                      Often mentioned case studies: Bremen and Hiroshima. Both today are modern cities, unlike Detroit that survived WWII intact.

                      http://en.wikipedia.org/wiki/Bombing...n_World_War_II

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                      • #12
                        I've seen bad steel from nearly every country that makes steel.Some of the worst have been from HERE,Germany,China and India.

                        Chinese galv pipe is the worst,pipe from Thailand and Korea is much better,don't even know if it's made here anymore.

                        All of the US,Canadian and Mexican structural steel and red iron has been consistent and decent quality.

                        One of the biggest improvements has been India.Most of the heavy plate (5/8"+) we get now is Indian made.Used to the composition was all over the place,hard spots,spots with sulpher,lows and highs in dimension etc.But now it's consistent and much better quality.

                        Hands down some of the best pipe I have ever cut and welded was South African,it worked like a dream.Oddly enough I was working that steel when the US still had a trade embargo on them.
                        I just need one more tool,just one!

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                        • #13
                          I have to comment, several have correctly stated that you can and inevitably will make crap steel, it is an unfortunate product of the process, you can however try to minimise the crap bit, galvanising was and in most parts seen as a crap converting process, crap in prime out, it dosent matter what you put in if you pickle correctly you get prime product out [there are limitations with high phos as wetting is a problem.
                          pipe and plate laminiation are a product of the casting process, invariably skin lamination is full of mould powder from the caster, mould conditions are usually at fault, sloppy casting and poor machine allignment result in lamination of thr slab, usually in patches, rolling stretches the patch out to hundreds of meters, slitting then rolling into tube will wrap the lam right round, result split tube or cracks.
                          Clean steel, this is best achived in big ladles, small plants would find it all but impossible to make ultra clean steel like DWI [drawn and wall ironed for cans eg beer, inclusions in the steel cause splitting in the can and the wall thickness of the steel is only as thick as paper so a lump of crap can and does make a hole]
                          anyone can make steel, and hardly anyone can make it consistantly, steel is sold mainly by mechanical properties ie hardness, %elongation, UTS, analysis is not a primary concern, mostly you get a range of chemistry, the more expensive specified grades have a tighter range,
                          if you walk into a stockholder and buy some round bar, you may get the best stuff in the world or a lump of crap, you never know,
                          ive had my ass chewed by a customer for making better steel than they expected to get, punches shears press tools all set up for a tough brittle grade and i made a softer lower phos, they were not pleased.
                          you can deal with crap so long as its consistent crap, quality variation is the problem.
                          excuse me if i went on a bit but 30 years of steelmaking/casting/rolling
                          in a well over 100 year old steelplant gets to you
                          regards
                          mark

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                          • #14
                            Hey Mark,

                            thanks for the info. Metal casting is like a black art. It is nice to hear from someone in the know.

                            Rob

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                            • #15
                              Two experiences:
                              The first was 20-25 years ago when I was building control panels. Got one back plate from a local fab shop rather than from Hoffman, the plate where we mounted motor starters, relays and such had hard spots, dulled a lot of drill bits, broke a lot of taps. Move over a little and drill and tap - no problem. The local shop got a batch of bad steel.

                              Second occasion, mentioned on this bbs before, was some forged and machined parts from China. The part started out as bar stock from the steel mill, chopped to length, forged to rough shape then machined. The bars were supposed to be continuous length, but the steel mill had some short ones so they just butt welded them together. One of the welds made it through the whole forging, machining and plating process and came to us where the weld separated during our final assembly. Better than in the vehicle.

                              In the course of investigating this last one, I "heard" things that would lead me to be wary of some imported trailer hitch balls.
                              Weston Bye - Author, The Mechatronist column, Digital Machinist magazine
                              ~Practitioner of the Electromechanical Arts~

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