As a component of mechanical equipment seamless tube is stronger and therefore more resistant to pressure and tension than a tube with a welded seam that’s because seamless tube is made from a solid bar of stainless steel rather than from a strip that’s rolled and welded into a tube seamless stainless steel tube is used when reliability is critical for example in aerospace engines nuclear equipment and medical devices a manufacturer purchases stainless steel tubes in a range of lengths diameters and thicknesses the engineers select the right starting size for the specific tube the customer has ordered each one is checked with a tape measure and then a large micrometer to measure the outside diameter engineer switch to a smaller micrometer to.
Measure the wall thickness there then wait if the raw material meets all the specifications production can begin the team insert one end of each tube into this rotary sweater it shapes the end to a point to enable it to fit through a die with a smaller diameter operatives spread lubricant onto a steel bar insert it into the other end of the tube then insert the pointed end through a draw die this carriage then grabs the protruding point and draws the full length of the tube through the die and over the steel bar the die reduces the tube to a smaller outside diameter while the bar sets the desired inside diameter the tube walls thin out and the tube elongates in the process the next machine’s two rollers apply pressure to the outside of the tube as it passes this expands the tube slightly creating a slight gap between the tube walls and the bar inside this enables the next machine to extract the bar finally the point is cut off the end of the tube the team.
Placed several tubes at the time in a degreasing unit which uses a cleaning solution to remove all traces of lubricant the tubes picked up during the drug process operatives then transfer the tubes to drying tanks positioning them at a slight downward angle as air blows through the tubes for about half an hour all of the cleaning solution either drains or evaporates to further clean the inside of the tubes operatives insert a fat wad into each one then squirt in some cleaning solvent they blast in compressed air to force the wat down the tube as that what travels the length of the tube it wipes the inside wall with the cleaning solvent next operatives strap the tubes to a belt that takes them on a 30-minute trip through a furnace the temperature inside is more than 1,000 degrees.
Celsius this intense heat softens the steel which is hardened as a result of having been pulled through the draw direly er this process is called annealing and it slightly warps the tubes so next they’re passed through a straightening machine then the entire cycle repeats until the tube is reduced to precisely the diameter and wall thickness the customer ordered the finished tube can be up to 40 times longer than its original starting length to ensure the structural integrity of each tube an electrical current is run around the circumference a break in the current indicates a defect which engineers then cut out with a saw before cutting the tube into the lengths the customer order the saw cuts leave burrs or rough edges so the cut ends are inserted into a deburring machine which.
Grinds the edges smooth the last step is to submerge the tubes in an acid solution to remove any iron particles picked up from the processing this prevents the tubes from rusting what they’re left with is a perfectly formed seamless tube ready to withstand the rigorous use that a normal seam tube would never be able to cope with and sadly it would seem it’s the end of the show.