Welded and Open Profile Design Tips

Steel Profiles Tips and Tricks for Designing

Having our own Engineering department, Tubecon has the ability to guide and assist our customers in the development of their welded steel section or high strength steel open profile.

Tubecon has the ability and experience to form structural and other steel tubes and open profiles from a variety of materials. These include 3CR12 (stainless steel), Domex, Supraform, S355 High tensile steel and many other.

This puts us in a position to assist our customer with their innovative requests. Though it is our policy not to say NO, some aspects are crucial when designing a customized steel section. Customer specific profiles can be divided into two groups:

Closed or Welded Steel Profiles:

These include steel sections such as D-sections, Flat or Elliptical Oval Tubes, Triangle Profiles and Dome Profiles to name some of the more standard steel welded profiles. We are most certainly not limited to only these sections but do have some advice on how to keep your tooling cost (needed to manufacture the steel closed profile) to a minimum. Click the link below to view some tricks regarding this.

Design Tips for Closed or Welded Steel Profiles

Open Profile (Not welded):

These sections include Zed Sections, Steel Top Hats, Sigma Profiles, Omega Sections, U and C-channels and a very wide variety of other cold formable steel profiles.  For the most part one has a bit more freedom in designing steel open profiles then with welded profiles. The main reason for this is that a welded profile is by enlarge limited to its mother tube (see explanation) where non-welded sections are limited by existing tooling, wall thickness and strip width. Click the link below to view some tricks and tips regarding the feasibility of your open profile design.

Design Tips for Open Profile

Closed Or Welded Steel Profile Tips

Closed or Welded Steel Profiles:

Mother Tube: To ensure the least possible tooling for your customized steel welded section it is important to try as far as possible to adhere to the circumference off a fast moving or standard round steel tube.

Tubecon uses the Electric Resistance Welding Process (ERW) which implies that a steel strip is formed incrementally, through a progressive set of rolls, along its longitudinal axis to produce a round hollow section.

The ends of the slit strip is heated with high frequency welding, thereafter being forced together by weld rolls to create a continuous weld over the length of the tube. After the structural hollow section has been welded the seam is cooled before moving through a set of sizing and shaping rolls. The sizing rolls are used to incrementally press the round tube into the desired shape. Most common shapes are rectangular and square steel tubes. The round tube, before going through the sizing rolls, is referred to as the mother tube.

Each cold formed profile steel tube, no matter what the dimensions, has to be formed from a round mother tube. If the mother tube is a standard it would imply that we do have the forming rolls and the tooling cost can be kept down to only the last couple of passes to form your desired structural hollow section.

Radii: As a rule of thumb the radii should not be less than the material thickness that the steel tube has to be rolled from. Though it is not impossible to achieve small radii it will also lead to breakage if pressure is applied to the tube.

Tolerances: Tight tolerances on your customized welded sections may have an increased price. If a customized profile tube is rolled for the first time, tighter tolerances will be difficult to achieve and wider tolerances are therefore preferable.

Open Profile Design Tips

Open Profiles

Radii: Use inside radii that are larger than material thickness. Radii that are too small or smaller than steel thickness will add strain to the gears and rolls. Tubecon's sales staff would be able to advise you on what sized radii should be used for your cold formed steel profile.

Symmetrical: If the profile is symmetrical it is easier to avoid the steel section from twisting. If your profile is a-symmetrical Tubecon would still be able to roll-form to your custom steel requirements.

Hole Punching: The diameter of the hole punched in the cold formed open section should preferably be larger than the thickness of the material used for forming the steel open section. Tubecon is able to punch a variety of holes in your roll formed steel section.

Tolerances: Keep the tolerances realistic. An advantage to custom cold forming is the fact that tight tolerances can be achieved. If, however, these tight tolerances are not needed and asked for it may have a serious cost implication your cold formed section. Tubecon is able to achieve tight tolerances on cold formed steel sections and our sales staff will be able to assist you should you have any enquiries.

Lip and Flange Length: Increasing the length of the lip on open profiles such as Top Hat sections, Zed Profiles and Lip channels ensures that the rolls does not take as much strain during the cold forming process. It is advisable to keep the flanges on U-channels to approximately three times the steel's thickness.

Large Radii: Large sweeping radii on your custom steel profiles are detrimental to tolerance control. Adding sharper bends to the steel section allows for more roll-forming accuracy.