I. Characteristics and Classification of Aluminum Alloy Vessels

Aluminum alloy has been used in shipbuilding for nearly a century. The emphasis on lightweight vessels in shipbuilding has increased due to aluminum's low density, high strength, rigidity, and corrosion resistance. Ships constructed with aluminum weigh 15-20% less than those made of steel. The material's advantages in toughness, corrosion resistance, and lower processing costs make it favorable for ship construction, enabling higher speeds and longer lifespans. This versatility has rapidly expanded aluminum alloy's usage in shipbuilding, providing a broad market for aluminum materials.

Aluminum alloys used in ships can be divided into deformed aluminum alloys and cast aluminum alloys. In the application of shipbuilding in various countries, from the superstructure of large surface ships, thousands of tons of all-aluminum ocean research ships, ocean merchant ships, and passenger ships, to the construction of hydrofoil boats, hovercraft, passenger ferries, catamaran passenger ships, traffic boats, landing craft and other high-speed passenger ships and military speedboats, a large number of deformed aluminum alloys are used. Cast aluminum alloy is mainly used in pumps, pistons, outfitting storm mine shells, and other parts.

P1 Aluminum Yacht

II. Welding Clients in Aluminum Alloy Vessels

Oulun (Dalian) Chuanye Limited Company, established in 2006, is a Sino-European joint venture specializing in the manufacture of aluminum alloy ships. So far, the company has designed, built, and delivered aluminum alloy boats: port pilot boat series, transportation boat series, high-speed fishing boats and luxury yachts, and other series, the construction of all kinds of boats not only in the major domestic ports and enterprises, institutions a large number of use, and exported to Europe, Africa, the Middle East, Southeast Asia and other countries.

P2 Oulun (Dalian) Chuanye Limited Company

III. Welding Challenges on Aluminum Alloy Vessels

The welding of the yacht hull framework with rib plate welds, mostly butt and fillet joints in the upright position, using vertical up welding with a regular pulse welding machine. The customer has been facing several production challenges:

1）Inadequate concentration of arc energy, leading to slow welding speeds and substantial workpiece deformation, making it difficult to control overall dimensions.

2）Poor weld formation, dark discoloration, the yacht body frame welding, and the rib weld is mostly butt, angle joint, using the normal assembly method, vertical upward welding.

3）Deficiencies in arc start and end points, requiring a lot of time to repair in the later stage and have high cost. Moreover, the depth of penetration is insufficient, and the mechanical properties are seriously decreased, which affects the overall quality and performance of the yacht.

P3 Yacht Hull Framework

IV. Features and Advantages of Dex PM3000S Welding Machine

To address these challenges, the recommendation is the Dex PM3000S welding machine utilizing the pulse aluminum welding process. The Dex PM3000S welder is a fully digital high-frequency intelligent inverter welding machine capable of full-position direct current, and pulse welding of materials such as carbon steel, stainless steel, and aluminum alloys. It provides the following advantages to resolve client issues:

1）Optimized control scheme and reasonable process parameters ensure smooth arc initiation, stable arc termination, and reduce welding deficiencies. Adjustable start and end arc parameters ensure overall weld quality.

2）Enhanced aluminum welding pulse technology makes the arc energy more concentrated, the fusion deeper, the welding speed faster, the heat input lower, the splatter less, ensures consistent shaping, and produces a silver-white color.

3）Multiple stored aluminum welding expert datasets allow for wide applicability and fine-tuning of pulse welding parameters based on on-site conditions to achieve superior welding results.

4）The wire feeder uses high-performance digital motors and a four-wheel drive system to ensure stable wire feeding, ensuring high-quality welding.

V. Welding Effect Comparison on Aluminum Alloy Vessels

By employing the Dex PM3000S welding machine, deficiencies in arc initiation and termination have largely vanished. Achieving a fusion depth of 2mm in fillet welds meets client requirements. Weld seams exhibit aesthetically pleasing scalloped patterns with a silver-white color. Concentrated arc energy, increased welding speed, and reduced heat input significantly minimize workpiece deformation, ensuring compliance with tolerance requirements while maintaining excellent mechanical properties of the weld seams.

P4 Weld Seam

VI. Application of Dex PM3000S Welding Machine

P5 Onsite Application of Dex PM3000S Welding Machine