2026-09-18
By Yuhong Holding Group Co., Ltd (浙江宇鸿伟业特钢有限公司) · Fin Tube & Heat Exchanger Specialists
When an overseas petrochemical refinery needed heat exchange tubing for the radiant section of a fired heater, Yuhong Holding Group Co., Ltd supplied a consignment of ASTM A106 Gr.B carbon steel studded fin tubes. This case walks through the product, the project requirements, the quality checks, and the packing and shipment of the order.
The customer operates a fired heater in which the tube surface is exposed to a high-temperature, corrosive flue gas stream and requires frequent cleaning. Studded fin tubes were selected because the welded studs significantly enlarge the external surface area, improve heat transfer, and stay reliable in dirty, corrosive service — an ideal match for radiant coil and raffinate oil duties in the oil and gas sector.
The consignment was produced to the customer’s approved datasheet, covering two base-tube sizes with a studded carbon steel fin:
| Item | 6″ tube | 4″ tube |
|---|---|---|
| Material | ASTM A106 Gr.B | ASTM A106 Gr.B |
| OD — NPS / mm | 6″ / 168.3 | 4″ / 114.3 |
| Average wall — SCH / mm | SCH 40 / 7.11 | SCH 40 / 6.02 |
| Length — mm/pc | 5228 | 5228 |
| Fin type | Studded (STUDDED), CS | Studded (STUDDED), CS |
| Stud thickness × height | 12.7 × 25.4 mm | 12.7 × 25.4 mm |
| Studs per plane | 18 | 10 |
| Plane spacing | 75 mm × 75 mm | 75 mm × 75 mm |
| Quantity | 44 pcs | 19 pcs |
| Unit weight | 303.00 kg | 170.00 kg |
| Total weight | 13.33 t | 3.23 t |
For both sizes the base tube is ASTM A106 Gr.B carbon steel, and the studded (STUDDED) carbon steel fin measures 12.7 mm in thickness and 25.4 mm in height — arranged 18 studs per plane on the 6″ (168.3 mm) tube and 10 studs per plane on the 4″ (114.3 mm) tube, on a 75 mm × 75 mm plane pattern. The 5228 mm piece length was matched to the customer’s radiant coil layout.
| Item | Specification |
|---|---|
| Application | Radiant coil, fired heaters, raffinate oil, boilers |
| Certification | ABS, BV, DNV, CCS, LR; EN10204 3.1 / 3.2 |
| Packaging | Iron frame case with plastic cap |
Because studded fin tubes are an advantage product for the group, the base tube is manufactured in-house and then processed into fin tube. Base tubes can meet the requirements of EN10204-3.1 and EN10204-3.2 certifications, and they undergo strict inspection before entering the fin processing plant. The fin factory follows disciplined working procedures and supervision systems, backed by an on-site laboratory that carries out routine tests to keep every batch consistent.
Before dispatch, the finished tubes were bundled and packed in strong iron frame cases fitted with plastic caps, protecting the stud tips and machined end faces from impact and moisture during long-distance sea freight. The iron frame construction keeps the long, studded lengths stable in transit, while the caps guard the critical end surfaces against corrosion and mechanical damage — a packing standard that keeps the consignment ready for immediate installation on arrival.
The order was completed and shipped on schedule, meeting the customer’s project timeline for the radiant coil package. Supported by a supply ability of up to 10,000 tons per month and payment terms of TT or LC, the shipment reflected the group’s ability to deliver certified, ready-to-install studded fin tubes to overseas refinery projects.
This case study was prepared by Yuhong Holding Group Co., Ltd (浙江宇鸿伟业特钢有限公司), a manufacturer of boiler tubes, heat exchanger tubes and fin tubes since 1990. The company exports 80–90% of its output to customers worldwide. Learn more at https://www.steelfintube.com.
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