boltseals

Bolt seals are tamper-evident security devices used to protect cargo during transport. They are widely employed on intermodal containers, trucks, railcars, and other closed enclosures. A typical bolt seal consists of a rigid steel bolt and a locking head. The bolt passes through the hasps on the container doors, and the locking head engages the bolt and is then secured by a unique serial-numbered locking mechanism. Once closed, the seal cannot be opened without cutting the bolt, providing a visible indication of tampering. The seals are designed for single use and are discarded when the container is opened.

Materials and construction: most bolt seals are made from hardened steel, sometimes stainless or coated to resist corrosion; the locking head may be aluminum or steel. They are designed to meet international standards, commonly ISO 17712, which defines performance criteria and requires unique identification, traceability, and tamper-evident features. Some versions are rated as high-security seals for cross-border shipments.

Usage and management: at origin, the seal number is recorded to match the shipment's documentation; on arrival, inspectors verify that the seal is intact and the number matches. If the seal is broken or mismatched, it indicates possible tampering. Different suppliers provide bolt seals with various lengths to fit different hasp sizes.

In summary, bolt seals provide a cost-effective, tamper-evident method for securing containers and other closed cargo enclosures during transport, with standardization and traceability as key features.