Auto Parts Industry

What is DOM Tubing? Drawn Over Mandrel (DOM) Round Mechanical Tubing is a cold drawn 1020/1026 electric resistance welded tube with all the flash removed prior to cold drawing. In comparison to other tubing, DOM round steel tubing is produced to more exact OD and ID tolerances, and has the highest weld strength possible. DOM STEEL TUBING MANUFACTURING PROCESSThe manufacturing process for DOM round steel tubing begins with coils of steel, which are slit to the proper width for the desired tube size. The strip is cold formed and passed through an electric resistance welder which joins the edges together, under pressure, to complete the tubular shape. After testing the weld’s integrity, the tubing is cut to length for further processing. The cold-drawing process creates a uniform, precision product with substantially improved tolerances, surface finish and tensile strength, increased hardness and good machinability. In this process, the tube is cleaned and annealed, and one end of each length is squeezed to a point so it can be gripped by the drawing mechanism. The tube is then drawn through one or more dies and over mandrels. This reduces the diameter of the tube and thins its walls to the required dimensions in a controlled fashion to provide the qualities desired in the finished product. Metallurgically, drawing improves the tube’s concentricity, tensile strength, hardness and machinability. Close dimensional accuracy is achieved through tight control of both outside and inside diameters. The Many Purposes of DOM TubingDrawn Over Mandrel tubing is used for a variety of applications and industries. The tubing is used for machinery, hydraulics, motorcycle frames, and bearings. Of course, these are just a few examples of what it is used for.  This type of tubing creates a seamless connection, unlike a welded tube. Because of this, DOM is usually chosen over welded tube where high pressure or large workloads are needed. Being sturdy and reliable, this tubing is often used in automotive parts, race car frames, motorcycle frames, and farming equipment. Drawn Over Mandrel tubing is available in many different sizes and specifications. The industrial tubing is used for a wide range of bushing and structural applications. When it comes down to a DOM tubing supplier, your number one choice is Detroit Nipple Works. Also, we meet all requirements of the tubing such as ASTM Specification A513 with a high degree of wall uniformity. In addition, we have a large selection of sizes to choose from.  BENEFITS OF DRAWN OVER MANDREL TUBINGCOST-EFFECTIVENESSClose tolerances allow DOM to be used for mechanical parts with minimal or no downstream processing.STRENGTHCold-drawing gives DOM high yield and tensile strength.UNIFORMITYDOM has uniform wall thickness and concentricity, as well as uniform mechanical properties. DOM tubing also has close OD and ID tolerances. Uniform grain structure and controlled hardness.APPEARANCESmooth and Clean OD and ID surfaces.CLOSE TOLERANCESDOM offers exceptionally close tolerances for OD, ID and wall thickness dimensions.SURFACE QUALITYOD and ID surfaces of DOM are free of oxide and scale and have a smooth, dense finish with no trace of the weld.MACHINABILITYDOM is easily machined, with only a nominal stock allowance for clean-up. It has excellent machining characteristics.WIDE RANGE OF SIZESDOM can be manufactured to an almost infinite range of OD and wall thickness dimensions by varying the size of the dies and mandrels used.

This kind of tubes is made by good quality seamless steel tube and formed by cold drawn process. This lemon steel tube is for the transmission shaft of the corn harvester, the transmission shaft of the agricultural machine, the drive shaft of the drive shaft of the agricultural machine.

Upset ForgingUpset forging increases the diameter of the workpiece by compressing its length. Based on number of pieces produced, this is the most widely used forging process. A few examples of common parts produced using the upset forging process are engine valves, couplings, bolts, screws, and other fasteners.Upset forging is usually done in special high speed machines called crank presses, but upsetting can also be done in a vertical crank press or a hydraulic press. The machines are usually set up to work in the horizontal plane, to facilitate the quick exchange of workpieces from one station to the next. The initial workpiece is usually wire or rod, but some machines can accept bars up to 25 cm (9.8 in) in diameter and a capacity of over 1000 tons. The standard upsetting machine employs split dies that contain multiple cavities. The dies open enough to allow the workpiece to move from one cavity to the next; the dies then close and the heading tool, or ram, then moves longitudinally against the bar, upsetting it into the cavity. If all of the cavities are utilized on every cycle, then a finished part will be produced with every cycle, which makes this process advantageous for mass production.These rules must be followed when designing parts to be upset forged:The length of unsupported metal that can be upset in one blow without injurious buckling should be limited to three times the diameter of the bar.Lengths of stock greater than three times the diameter may be upset successfully, provided that the diameter of the upset is not more than 1.5 times the diameter of the stock.In an upset requiring stock length greater than three times the diameter of the stock, and where the diameter of the cavity is not more than 1.5 times the diameter of the stock, the length of unsupported metal beyond the face of the die must not exceed the diameter of the bar.