Based in the major port city of Dalian, China, Dalian QianLong Marine Engineering Co., Ltd. is a specialized technical service provider focused on underwater engineering and commercial diving operations. Since its establishment in 2008, the company has developed a dedicated operational infrastructure designed to support the maritime, offshore, and port construction sectors. Rather than operating as a general ship chandler or trading house, the firm functions as a hands-on engineering contractor, deploying certified professional divers and advanced submerged equipment to maintain vessel performance and structural integrity.
The company’s core identity revolves around its ability to execute complex subsea tasks without requiring vessels to drydock. This operational capability is supported by an extensive network of service stations located along China’s coastline. Beyond its headquarters in Dalian, the enterprise manages branches in key maritime hubs including Shanghai, Qingdao, Tianjin, Guangzhou, and Shenzhen. This wide geographic footprint allows the company to mobilize diving teams and equipment rapidly to almost any major port in the region, ensuring that international vessels calling at Chinese terminals receive timely maintenance.
In terms of daily operations, Dalian QianLong Marine Engineering concentrates on underwater hull maintenance and inspection services. The firm utilizes hydraulic cleaning systems to remove marine fouling from ship hulls, a critical process for restoring fuel efficiency and reducing drag for ocean-going fleets. Additionally, their teams perform high-precision propeller polishing, underwater cutting, and welding repairs for hull cracks. The company also conducts rigorous in-water surveys (IWS) using underwater CCTV and high-resolution photography, providing essential data for classification societies and shipowners regarding the condition of submerged assets.
The company’s technical standards are validated by approvals from a broad spectrum of members of the International Association of Classification Societies (IACS). The firm holds certifications from major regulatory bodies such as ABS, DNV, Lloyd’s Register, and ClassNK, enabling it to perform certified underwater inspections that meet global maritime safety requirements. While primarily serving the commercial shipping industry—including container lines, bulk carriers, and tankers—the company also extends its engineering expertise to offshore oil platforms, bridges, and hydroelectric projects, handling tasks such as anode replacement and anti-erosion inspections. Through these specialized activities, Dalian QianLong Marine Engineering plays a vital role in the maritime logistics chain, helping operators extend the service life of their vessels and infrastructure.
