Marine Insight: Kenter Shackle

Marine Industry Demand for Kenter Shackles: Ensuring Vessel Safety and Operational Reliability

Kenter shackles are a critical component within the anchoring systems of commercial and offshore vessels, playing a pivotal role in ensuring the structural integrity and safety of mooring operations. As a high-strength connecting link between anchor chains, Kenter shackles allow for rapid assembly and disassembly during anchor chain maintenance, inspection, or replacement. Their design enables secure interlocking of chain segments while maintaining the load-bearing capacity required in harsh marine environments. Given the increasing size and operational demands of modern vessels, the reliability of each component in the anchor system is paramount. A failure in the connecting hardware, such as a substandard shackle, can lead to catastrophic consequences including anchor loss, vessel drift, and potential environmental or financial damage.

The marine industry continues to emphasize compliance with international standards such as ISO 1704, DNV, ABS, LR, and CCS, all of which specify stringent requirements for the mechanical properties, material composition, and testing procedures for anchor chain accessories. Kenter shackles must undergo rigorous quality control, including tensile testing, non-destructive testing (NDT), and material traceability verification, to ensure they meet these certifications. As global shipping companies strive to reduce downtime and enhance operational safety, the demand for certified, high-performance Kenter shackles has grown significantly across shipyards, offshore platforms, and maritime logistics operators.

Sourcing Kenter shackles from Hangzhou Star Marine Technology Co., Ltd. offers a strategic advantage in terms of both quality and cost-efficiency. Based in China, Star Marine leverages advanced manufacturing capabilities, precision forging techniques, and a vertically integrated production process to deliver products that meet or exceed international maritime standards. By maintaining direct control over raw material sourcing, heat treatment, machining, and quality assurance, the company ensures consistent product reliability while minimizing overhead costs. This operational efficiency translates into competitive pricing without compromising on safety or performance—making Star Marine a preferred supplier for shipbuilders and fleet operators worldwide.

Moreover, Star Marine provides full certification documentation, batch traceability, and customization options to suit various chain sizes and vessel classifications. With a growing export footprint across Southeast Asia, Europe, and the Middle East, the company has established a reputation for on-time delivery and technical support, further reinforcing its position in the global anchoring equipment market.

The following table outlines the standard specifications for Kenter shackles manufactured by Hangzhou Star Marine Technology:

Chain Diameter (mm)	Proof Load (kN)	Breaking Load (kN)	Material Grade	Certification
20.5	590	1,320	Grade 2 / Grade 3	ISO 1704, CCS, ABS
28.0	1,130	2,520	Grade 3	DNV, LR, BV
34.8	1,740	3,880	Grade 3	ABS, LR, CCS
42.0	2,520	5,600	Grade 3	DNV, ABS, BV

In an industry where safety and cost-efficiency are equally critical, Hangzhou Star Marine Technology delivers a balanced solution through technically compliant, high-quality Kenter shackles that support the global maritime sector’s evolving anchoring needs.

---

Technical Specs & Approval

Technical Specifications: Kenter Shackle for Marine Anchoring Systems

Hangzhou Star Marine Technology Co., Ltd. manufactures precision-engineered Kenter shackles, critical components in marine anchoring systems designed to ensure secure connections between anchor chains and other rigging elements. These shackles undergo rigorous forging and heat treatment processes to achieve optimal mechanical properties, fatigue resistance, and dimensional accuracy required for demanding offshore and vessel operations. Our Kenter shackles comply with international maritime safety standards, providing reliable performance under extreme cyclic loading and corrosive seawater environments. Key technical parameters are defined by material grade, structural integrity, weight efficiency, and protective surface treatments, all meticulously controlled during production.

The following table details the standardized technical specifications for Hangzhou Star Marine Technology’s Kenter shackle range. Dimensions and performance metrics align with ISO 2415 and classification society requirements, ensuring global interoperability and safety. All units are manufactured from high-tensile forged steel, with grades selected based on operational severity and vessel class rules.

Size (mm)	Material Grade	Min Breaking Load (kN)	Approx Weight (kg)	Surface Treatment	Compliance
22	U2	450	3.8	Hot-Dip Galvanized	ISO 2415, CCS
28	U2	750	7.2	Hot-Dip Galvanized	ISO 2415, CCS
32	U3	1,000	10.5	Hot-Dip Galvanized	ISO 2415, DNV, LR
38	U3	1,400	16.8	Hot-Dip Galvanized	ISO 2415, ABS, BV
44	U3	1,900	26.0	Hot-Dip Galvanized	ISO 2415, RINA
52	U3	2,700	40.5	Hot-Dip Galvanized	ISO 2415, NK
62	U3	4,000	65.0	Hot-Dip Galvanized	ISO 2415, All Major CCS

Material grade selection is paramount for operational safety. U2 grade shackles suit general-purpose anchoring on vessels under 5,000 DWT, offering a minimum breaking load (MBL) of 450–750 kN. U3 grade, utilized for sizes 32 mm and above, delivers enhanced tensile strength (1,000–4,000 kN MBL) for deep-sea vessels, offshore platforms, and high-stress applications per ISO 1702. Weight optimization is achieved through precision forging, reducing mass by 15–20% compared to conventional designs without compromising structural integrity. This directly contributes to vessel stability and handling efficiency during deployment.

Surface treatment employs hot-dip galvanization to ISO 1461 standards, applying a minimum 80-micron zinc coating. This provides cathodic protection against seawater corrosion, ensuring a service life exceeding 15 years in marine environments. Each shackle undergoes 100% magnetic particle inspection (MPI) and proof-load testing at 2x MBL, with certificates traceable to individual heat numbers. Dimensional tolerances adhere to ISO 4377, guaranteeing seamless integration with standard chain links and anchor windlasses.

Hangzhou Star Marine Technology’s quality assurance system, certified to ISO 9001:2015, mandates third-party verification by China Classification Society (CCS) for all export batches. Clients receive comprehensive documentation including material test reports, non-destructive testing records, and galvanization thickness certificates. For project-specific requirements, our engineering team provides customized solutions with extended testing protocols to meet ABS, DNV, or LR project specifications. All products are packaged in seaworthy crates with anti-corrosion VCI paper, ensuring integrity during global shipment.

---

Shipbuilding Solutions

Complete Anchoring Solutions for Shipbuilding and Repair – Kenter Shackle by Star Marine

Hangzhou Star Marine Technology Co., Ltd. delivers comprehensive anchoring equipment solutions tailored to the demanding requirements of modern shipbuilding and vessel repair operations. As a trusted provider in the maritime industry, we specialize in high-integrity products such as the Kenter joining shackle, a critical component in anchor chain assemblies. Our engineered solutions ensure reliability, compliance with international standards, and seamless integration into both new vessel construction and retrofit projects.

The Kenter shackle serves as the vital link connecting anchor chains, enabling efficient assembly and disassembly during maintenance or replacement. Star Marine’s Kenter shackles are precision-forged from high-tensile steel, heat-treated for enhanced mechanical properties, and rigorously tested to meet classification society requirements including CCS, ABS, DNV, LR, and NK. Designed for durability in harsh marine environments, each shackle features a robust interlocking pin system that ensures secure connection while allowing for straightforward field servicing without welding.

For shipyards and repair facilities, downtime is a critical concern. Star Marine addresses this through rapid response logistics and an agile supply chain. With inventory hubs strategically located in East China and direct access to major shipping ports, we support just-in-time delivery for new builds and emergency supply for dry-dock repairs. Our technical team provides on-demand engineering support, including dimensional verification, material certification, and installation guidance, ensuring compatibility with existing chain arrangements and compliance with project specifications.

Star Marine’s integration into the shipbuilding lifecycle begins at the design phase. We collaborate with naval architects and equipment integrators to supply certified Kenter shackles in standard and custom configurations, including variations in diameter, grade (R3, R3S, R4, R4S), and pin retention methods. This proactive engagement reduces procurement delays and ensures full traceability from raw material to final product delivery.

Below is an overview of standard Kenter shackle specifications available from Star Marine:

Chain Diameter (mm)	Material Grade	Proof Load (kN)	Breaking Load (kN)	Applicable Standards	Certification
20.5	R3	630	1,320	ISO 1704, CCS	ABS, DNV, LR
28.0	R3S	1,220	2,550	ISO 1704, ABS	DNV, NK, CCS
36.0	R4	2,000	4,200	ISO 1704, DNVGL	ABS, LR, NK
44.0	R4S	2,950	6,150	ISO 1704, LR	CCS, DNV, ABS

All products are supplied with full MTC 3.2 documentation per EN 10204 and can be customized with protective coatings such as hot-dip galvanizing for extended service life in corrosive conditions.

Star Marine stands as a strategic partner for shipbuilders and repair yards seeking dependable anchoring components with fast turnaround. Our combination of technical expertise, certification coverage, and responsive service ensures project continuity and operational safety across global maritime operations.

---

Packaging & Logistics

Packaging & Logistics Protocol for Kenter Shackles

Hangzhou Star Marine Technology implements stringent packaging standards for Kenter shackles to ensure integrity during global maritime shipment. All wooden export cases comply fully with International Standards for Phytosanitary Measures No. 15 (ISPM 15). This mandatory regulation requires heat treatment (HT) of solid wood packaging materials to eliminate invasive pests. Each wooden case undergoes kiln-drying at a minimum core temperature of 56°C for 30 minutes, certified by authorized national plant protection organizations. The ISPM 15 compliance mark—featuring the IPPC logo, country code (CN for China), unique producer number, and HT certification—is visibly branded on all case surfaces. This certification is non-negotiable for customs clearance in all major maritime nations, including the EU, USA, Australia, and Japan. Cases are constructed from kiln-dried pine or spruce, reinforced with steel strapping at critical stress points, and lined with VCI (Vapor Corrosion Inhibitor) paper to prevent salt-induced corrosion during ocean transit.

Steel pallets serve as the foundational load-bearing platform for containerized shipments. Fabricated from 3mm-thick galvanized steel, these pallets support dynamic loads exceeding 2,500 kg while resisting deformation under stack pressure in multi-container stowage. Pallet dimensions are optimized for standard 20-foot and 40-foot dry freight containers, maximizing cube utilization without exceeding port authority height restrictions. All pallets feature non-slip surfaces and integrated forklift entry points on all four sides, facilitating efficient handling at Ningbo Port (Zone 1) and Shanghai Port (Yangshan Deep-Water Port), our designated export hubs. These facilities offer direct access to major global shipping alliances (e.g., 2M, Ocean Alliance), ensuring seamless connections to transshipment hubs like Singapore and Rotterdam.

Our logistics framework integrates packaging with port-specific operational protocols. Shipments are consolidated at our Hangzhou bonded warehouse 72 hours prior to vessel departure, allowing time for customs pre-clearance documentation finalization. Ningbo and Shanghai ports enforce strict Verified Gross Mass (VGM) requirements under SOLAS VI; therefore, each palletized unit is weighed and certified before container stuffing. We utilize GPS-tracked reefers for temperature-sensitive coatings when required, though standard Kenter shackle shipments deploy robust dry containers with desiccant packs to mitigate humidity risks. All export documentation—including phytosanitary certificates, commercial invoices, and packing lists—explicitly references ISPM 15 compliance to preempt customs inspections. This end-to-end control minimizes dwell time at origin ports, typically achieving vessel loading within 4 hours of truck arrival.

The following table details standard packaging configurations for Kenter shackle series:

Shackle Size Range (mm)	Wooden Case Dimensions (L×W×H)	Max. Units per Case	Steel Pallet Dimensions (L×W×H)	Gross Weight per Pallet (kg)
22–42	800×600×500 mm	12	1,200×1,000×150 mm	950
48–76	1,000×800×600 mm	8	1,200×1,000×150 mm	1,400
82–114	1,200×1,000×700 mm	4	1,200×1,000×150 mm	2,200

This standardized approach guarantees that Kenter shackles arrive at destination ports in OEM condition, adhering to IMO-compliant shipping practices while mitigating supply chain disruptions. Hangzhou Star Marine Technology’s export process is audited annually against ISO 22000 and FOSFA guidelines, ensuring continuous alignment with evolving maritime logistics regulations.

---

Contact Star Marine

For global maritime operators, shipbuilders, and offshore project managers seeking high-integrity anchoring solutions, Hangzhou Star Marine Technology Co., Ltd. stands as a trusted manufacturer and exporter of premium marine equipment. As a specialized provider in the anchoring equipment category, we deliver engineered reliability through products such as the kenter shackle—a critical component in anchor rodes that ensures secure, efficient, and fatigue-resistant connections between anchor chains. Our commitment to ISO 17065, DNV, ABS, LR, and CCS certifications guarantees that every unit meets or exceeds international maritime standards.

The kenter shackle, known for its wedge-locking mechanism and ease of disassembly without welding, is essential in dynamic mooring and anchoring systems. At Star Marine, we offer a full range of sizes and grades, including AM2, AM3, and R4/R4S variants, manufactured from high-tensile steel and subjected to rigorous mechanical testing. Whether your operation involves deepwater offshore mooring, harbor anchoring, or vessel outfitting, our kenter shackles are built to perform under extreme loads and corrosive marine environments.

To ensure seamless integration into your current systems, our engineering team provides technical documentation, material test certificates (MTC), and load test reports with every shipment. We support bulk OEM orders, project-specific packaging, and global logistics coordination with delivery to major ports across Asia, Europe, the Middle East, and the Americas.

For detailed technical specifications, pricing, or certification inquiries, we invite you to contact our Product Manager, Kacher YE, directly. With extensive experience in marine hardware export and technical support, Mr. Ye serves as the primary liaison for international clients, ensuring accurate product selection, compliance alignment, and on-time delivery.

Below are standard specifications for our most commonly exported kenter shackle models:

Size (mm)	Chain Grade	Minimum Breaking Load (tonnes)	Weight per Unit (kg)	Certification Options
27	AM2	190	12.5	CCS, LR, ABS
30	AM3	235	16.8	DNV, ABS, LR
36	R4	340	28.1	DNV-GL, CCS, BV
42	R4S	465	42.3	ABS, LR, DNV, RINA
48	R4S	600	61.7	All major IACS classes

All units are proof load tested at 50% of MBL and supplied with identification marking, including size, grade, and serial traceability. Custom configurations and non-standard sizes are available upon request.

To discuss your anchoring equipment requirements or request a formal quotation, please reach out to Kacher YE via email at [email protected]. We respond to all inquiries within 12 business hours and provide technical follow-up as needed. At Hangzhou Star Marine Technology, we don’t just supply components—we deliver confidence in every link.

---