Q. How is SMART stainless steel composite tubing made?
A. Mild steel strip of requisite grade is rolled and HF welded into a tube. Then, as the formed tube passes through the second welding heads, a sleeve of stainless steel strip is formed around the mild steel tube and TIG welded. The combination is passed through final rollers to straighten the tubes.
Q. What grade of stainless steel and mild steel does SMART use to manufacture stainless steel composite tubes?
A. The stainless steel outer sleeve is in stainless steel grade 304 with 316 to follow. The mild steel is in grade IS513/S195/S235.
Q. How thick is the stainless steel layer and mild steel layer?
A. Outer stainless steel layer thickness is 0.3mm and balance is mild steel layer of usually 0.9 to 1.2mm. But higher thicknesses of both MS (1 to 2.5mm) and SS (0.3-0.7mm) can be used for large requirements.
Q. Is the bond airtight?
A. This is the heart of the technology. The sophisticated rolling process ensures that the stainless steel outer sleeve is rolled tightly around the mild steel core leaving no air gap.
Q. Can SMART tubes be bent and formed?
A. The material can be manipulated in any way that would normally be used for stainless steel or mild steel. Standard elongation values of both the mild steel IS513 and stainless steel S304 shall be applicable. We recommend using rotary Draw bending with wiper die & flexible mandrel for good quality bending.
Q. Can SMART tubes be cut?
A. Material can be cut using normal saw blades for stainless steel, e.g. 5/8 variable pitch or laser cutting using Oxygen or Nitrogen.
Q. Can SMART tubes welded?
A. The material is welded as normal stainless steel e. g. TIG welding, MIG technique with argon shielding gas. Using SS309 electrode and at low amperage. Detailed welding instruction in different languages and video showing the manual welding are available on our website.
Q. What is the life of stainless steel?
A. The outer layer is made of recognised grades of stainless steel and has the usual inherent properties associated with the grade.
Q. What about internal corrosion of inner layer of mild steel?
A. The ends of the tubes should be capped with stainless steel or joined by full welding to other similar sections, leaving the inner with no exposure to air or moisture to form corrosion. If done properly, there will not be any internal corrosion. Even if some air gap remains at the end, the corrosion rate due to indirect exposure to moist air will be very very slow.
Q. Will contact with Mild Steel induce corrosion in stainless steel?
A. Not at all. On the contrary, MS will act as a sacrificial anode and enhance the corrosion resistance of SS layer.
Q. Is it possible to make specific tube sizes?
A. Any size of tube from 19.05mm up to 63.50mm with various wall thicknesses can be made for regular requirement against order.
Q. What polished finish is available?
A. Standard finish in production is bright polished or Mat finish but we can make the material in any particular polished finish for regular requirement against order.
Q. Can SMART tubes be painted?
A. The material will easily take both wet paint and powder coating finishes provided normal priming and preparation is carried out.
Q. In what lengths is SMART available?
A. The SMART material is manufactured in 6 meter lengths as standard though longer or shorter lengths are available upon request.
Q. Are bends & fittings of composite tubes available in the market?
A. It will be our endeavor to provide bends & fittings made of clad tubes. But in case of nonavailability with your dealer, you can use bends and fittings of equivalent grade of SS tubes