Titanium tubing with enhanced I.D. and O.D. surfaces is also available. Since the modulus of elasticity of titanium is lower than that of some of the copper alloys that it replaces, and, because it is usually used in thinner walls due to its high corrosion resistance, titanium tubed heat exchangers require shorter support plate or baffle spacings. Table 12 shows the approximate span reduction required for existing exchangers designed for other materials and being tubed with titanium. If the existing exchanger using copper alloy tubes of the gage shown operated without vibration damage, then reducing the spacing by the amount shown will give a comparable deflection of the titanium tubes. The chemical process industry uses a great deal of titanium in sheet and plate form in addition to tubes and plate used in heat exchangers.
Construction can be solid titanium, titanium-clad steel or steel vessels with titanium linings.
Lined vessels or equipment can consist of loose or mechanically fastened liners and may not be suitable for rapidly changing or low pressure conditions. Loose linings are generally positioned using gasketed flanges, whereas fastened liners frequently utilize titanium bolts to achieve liner attachments. This technique is often the most cost effective approach for new construction or for the retrofitting of vessels and ducting operating at low to moderate pressures and temperatures. Titanium-clad steel construction is favored at high pressures where very heavy walled vessels are required. Titanium piping is available in seamless or seam-welded forms.