Jacketing

Jacketing is the process of applying an outer protective layer, or jacket, to a component, equipment, or system. The jacket serves as environmental and mechanical protection, moisture control, and, in many cases, thermal or chemical containment. Jackets are designed to suit operating conditions and may be integral to the component or removable for maintenance.

In electrical engineering, jacketed cables and wires feature an outer jacket that shields insulated conductors from moisture, abrasion, chemicals, and sunlight, while meeting fire and flame ratings. Materials commonly used include PVC, polyethylene, and various elastomers; jackets may be UV-stable or halogen-free to meet specific safety requirements.

In piping, vessels, and process equipment, jackets provide thermal insulation, corrosion protection, and leak containment. Some designs use a single jacket with minimal insulation, while double jackets create an interstitial space for insulation material to be installed between the inner wall and outer jacket. For cryogenic or high-temperature services, jackets help maintain process temperatures and reduce heat gain or loss.

Manufacturing and design considerations include selecting jacket material compatible with the process fluid, temperature, and pressure; ensuring proper sealing at joints and ends to prevent moisture ingress; choosing fixed, removable, or adjustable configurations; and selecting appropriate installation methods such as cladding, overmolding, or mechanical attachment. Quality assurance typically involves leak testing and visual inspections.

Advantages of jacketing include extended service life, improved safety, and reduced heat loss, though it can add weight and cost, and improper sealing can create moisture traps between the jacket and insulation. See also jacket, insulation, and cladding.