We frequently field questions regarding the distinctions between Drawn Over Mandrel (DOM) Tubing and Cold Drawn Seamless (CDS) Tubing. Both types are renowned for their precision tolerances that enhance size accuracy. A key distinction lies in the fact that DOM is a welded tube, whereas CDS is manufactured without seams. Let’s explore these tubing types more closely.
Drawn Over Mandrel Tubing (DOM)
DOM is a cold drawn tube made from 1020/1026 steel that undergoes electric resistance welding with all surface impurities removed before the cold drawing process. This method results in notably tight tolerances for both the outer and inner diameters and offers the strongest possible weld strength. DOM tubes are available in sizes ranging from 0.188” in outer diameter to 12.000” with wall thicknesses spanning 0.028” to 0.625”.
DOM Tubing Manufacturing Process
The production of DOM begins with a large steel coil that is slit into strips tailored to the tube dimensions required. These strips are cold-formed and welded along their edges through electric resistance welding, forming a tubular shape. The tube is subsequently cleaned, annealed, and then drawn through dies over a mandrel, which eliminates any internal weld seam and ensures a smooth internal finish.
Advantages of DOM Tubing
DOM is highly cost-effective due to its tight tolerances, concentricity, and superior surface finish on the outer and inner diameters, allowing the tubing to be utilized with minimal processing post-manufacture. To discover specific applications of DOM tubing.
Cold Drawn Seamless Tubing (CDS)
CDS tubing is crafted from 1018/1026 steel, initially starting as hot-rolled material. The cold drawing of this steel not only refines its physical properties but also enhances its dimensional tolerances beyond what hot rolling can achieve.
CDS Manufacturing Process
The process begins with solid round steel billets that are pierced to form a hollow center. These tubes are then rolled to reduce their diameter and elongate. After cooling, the tubes undergo further processing through a die and over a mandrel plug to ensure precise dimensions.
Benefits of CDS Tubing
While CDS tubing may not have as tight tolerances as DOM, it can be produced with considerably thicker walls, lending it superior strength and hardness. This makes it ideal for components requiring extensive machining, resulting in a better appearance after such modifications. CDS is popular across various industries due to these attributes; to see how it is applied.
For further details on the chemical composition, tolerances, and grades of these materials, click the product name below.
