Like welded spiral finned tubes, this welded configuration can be used for practically any heat transfer application, and is particularly suited to high temperature, high pressure applications with high fin-side temperatures. The choice of longitudinal finned tubes versus helical finned tubes seems to be governed mainly by geometric considerations. For example, some heater configurations consist of finned tubes inserted inside other tubes — longitudinal finned tubes are the obvious choice for such applications. In other cases, users prefer longitudinal finned tubes for installations where the tube will be oriented in a vertical direction — the fin orientation facilitates fluid drainage on the fin side of the tube. The longitudinal fin configuration is most commonly used in shell and tube type applications such as in double-pipe and multi-pipe heat exchangers where the longitudinal finned tube is telescoped inside the bore of a larger tube shell. Heat is transferred between the fluid passing through the bore of the finned tube and the fluid passing through the bore of the shell. Fluids passing through the bore of the shell are forced between the longitudinal fins. In this case, a helical fin would block the flow of the fluid, rather than allowing the fluid to run between the fins.
Longitudinal Finned Tubes are produced by resistance welding fins in the longitudinal direction along the length of the tube. The fin strip is first formed into a U-shaped channel, such that each leg of the U will form a fin. The channels are cut to the appropriate length and then oriented along the length of the tube and resistance welded in place. The channels are welded in pairs, diametrically opposed — therefore the number of fins specified must always be a multiple of four.
For a given pipe or tube size, the desired heat transfer surface area per unit length of tube can be obtained by specifying the appropriate fin height and number of fins. The maximum number of fins is dependent upon the tube outside diameter — larger OD tube can accommodate a greater number of fins.
Dimension and Material
The following table shows Simcan’s manufacturing capabilities:
12 to 273 (mm)
3/8” to 10”(NPS)
Tube Wall Thk.:
2.11 to 25.4 (mm)
0.08” to 1”
No practical limit
No practical limit
1.0 to 1.5 (mm)
0.04” to 0.06”
5 to 25 (mm)
0.2” to 0.98”
1U to 36U
1U to 36U
* This table is used as a general guide to our capabilities, please call us for any other customized cases.
Codes and Standards
As per drawings and client’s Requirements
Surface Treatment and Protection
Each tube except stainless material will be polished by polishing machine to near white condition before welding.
After welding, the finned tubes will be coated with anti-rust oil for transportation and site storage purpose, normally the coat will provide a period of 3 months prevention, any other coating material for longer prevention is also available as per clients’ requirements.
Each package is designed and made according to seaworthy packing standard and clients’ handling and lifting capability.
Finned tubes will be packed into steel frameworks and wrapped with weather proof PE film and plywood board covering up. In addition, each row of finned tubes will be isolated from adjacent with plywood bar to prevent rigid impact during transportation. For all exporting packages, we only use plywood instead of wood for fumigation free purpose.
As a professional supplier, Simcan does not only manufactures products but also has full capability on preparing and submitting documents as listed below but not limited to:
Design and Fabrication Schedule
Drawings and data
Inspection and Test Plan (ITP)
Daily, weekly or monthly progress report
A complete set of final archive including
Raw Material Mill Certificates
Product Conformity Certificate
Inspection Reports including Material Receipt Inspection Report, Test Report etc.
Test report by world reputable third party such as TÜV, BV, SGS, Lloyd's, ABS, Intertek(Moody), Shanghai Jorson etc. if any
Packing List and Proforma Invoice
Certificate of Origin or any other documentation mandatory for clients’ customs clearance or tax preference