what is the surface roughness of Forged steel??? and how pipes are forged???
480781
forged steel can be polished to a mirror finish.  The forging process requires heat and pressure (usually impact pressure) which helps align the crystals in the steel for a stronger product.  the following is speculation: a pipe made of forge steel is likely heated to a medium red/orange colour and extruded like pasta. tho i suppose it could also be cold rolled (just like it sounds) and perhaps welded also.  any imperfections can be ground off and polished.
117218
steel, pump, vanes......
403489
Go to azom.com they have info on both 304, 316 and many other metals.\n\nIn a nut shell, 316 stainless steels are more corrosion resistant than 304 stainless steels
143139
Carbon Steel is probably your best bet, thats traditional.\n\nSome sword makers today use swedish powdered steel but I hear its really pricey but I like carbon steel better.\n\nI suggest you get some books on the forgeing of Katana, they are expensive books too.\n\nGood Luck, You'll probably need it, it takes alot of practice and experiance to make a good Katana!
21884
http://www.uyseg.org/industryanimated/teachers%20notes/extrusion_moulding.pdf\nThis file is good\n\nhttp://www.atplas.com/poly/ateva/moulding.htm\n\nExtrusion Moulding is a manufacturing process used to make pipes, hoses, drinking straws, curtain tracks, rods, and fibres\nhttp://en.wikipedia.org/wiki/Extrusion_Moulding
42980
it's called cathodic protection. the magnesium is sacrificed so the iron or steel pipe will last longer.
283977
Density(g/cm3) Steel Grade \n7.93 201,202,301,302,304,304L,305,321 \n\n7.98 309S,310S,316,316L,347 \n\n7.75 405,410,420 \n\n7.70 409,430,434 \n\nThere are some familiar Density of stainless steel above. Wish it be helpful.
731199
The first three answers are correct, but confusing. Let me see if I can't simplify this for you. \n\nThe pipe expands in all directions. Assume that the pipe is made of a uniform material, like copper, so we can say that it expands uniformly in all directions.\n\nYou must understand that the metal expands uniformly per unit of measurement. Think of a strip of metal, first. (our piece of tubing cut down the side and unrolled flat.) This means not only that the length, width and thickness expand-- it also means that it will expand so much PER UNIT.\n\nSuppose the copper will expand 1 mm per cm. (We'll use metric, just to keep it simple, because everything will be in tens.) \n\nIf the thickness of the copper strip is 1 cm, \nit will expand to 1.1 cm, or 1 cm plus (1 x 1mm.)\n\nIf the width of the strip is 20 cm, \nit will expand to 22 cm, or 20 cm plus (20 x 1 mm.)\n\nIf the length of the strip is 200 cm, \nit will expand to 220 cm, or 200 cm plus (200 x 1 mm.)\n\nNow, suppose we roll the strip back into a tube again. \n\nThe inner circumference of the tube started out as 20 cm, and the diameter was 20/ pi (which is something less than six cm.)\n\nThe new inner circumference is 22 cm, and the new diameter is 22/pi, which is greater than seven cm. \n\nSo, the metal expands proportionately in all dimensions, and the with of the strip (the circumference of the tube, and thus the diameter) expands MUCH MORE than the thickness of the strip, (which is the same as the tube wall). \n\nIs physics cool, or what?\n\n10 NOV 06, 0419 hrs, GMT.
377534
errr, grind metals to a fine powder and mix them together and press them and you can get alloys physically impossible to make by forging.\n\numm, grind metal very fine so the oxidise and use them to make metal fires, such as "thermalite" for welding traintracks.
168038
You would have to look into the properties for AMS, ASTM, AISI, ASME, Federal, Mil and SAE steels. It all depends on what type of steel you are using. Stainless, mild and what type of hardness (1/2 or 1/4 for stainless) that you need and what the purpose of the part is going to be used for
123326
Most corrosion is on the outside so it really doesn't make a difference, hot or cold. What determines corrosion is the \nenvironment outside of the pipe.
553406
Many types of chrome polish on the market....\n\nI've used shaving cream and done well with it on exhaust pipes... but Chrome Polish is your best bet
799770
Sounds like a heat transfer question.  If so it depends on how the tube is being used.  \n\nFor a single pipe exposed to heat transfer to air, the outer diameter is used to determine the surface area.  For shell and tube exchangers they have charts for making the determination based on the tube configuration and baffling.
959728
Hi. As with most things it depends on the cost of manufacture. : http://www.steelonthenet.com/commodity_prices.html
438539
You should find that under the ASTM Manual for steel. Your engineering department should have a copy, otherwise try finding it on line.
323359
Ingot Casting : Process Description\n\n After it is refined, the molten steel is tapped into refractory lined ladles. The steel is then teemed (poured) into a series of ingot molds. After the ingots solidify, the ingot molds are stripped and the ingots are placed in soaking pits for heating and to equalize the internal and external temperature. Following the soak, the ingots are hot rolled in large primary rolling mills to produce slabs, blooms, or billets depending on the final products desired.\n\nMore info in link below:
227707
yeah, if I could scratch it with a steel knife.  Pyrite would be flaky and would feel like glass almost. Gold would be soft and I could sink a knife into it a bit.  I don't know what silver feels like but I could tell it after I found the first two.