Seamless tubing: AP, BA and EP finishes
Define the surface finish as part of the tube specification. Fluidline can discuss annealed and pickled, bright annealed and electropolished tubing requirements for your project.

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Discuss dimensions, material documentation and service conditions with our team.
Request this product ↗Compare the finish designations
| Finish | Meaning | Include in the enquiry |
|---|---|---|
| AP | Annealed and pickled | Required surface condition, cleanliness and applicable standard |
| BA | Bright annealed | Required internal and external finish and delivery condition |
| EP | Electropolished | Required surface roughness, measurement basis, cleaning and packaging |
These terms describe finish requirements; they do not replace the material grade, manufacturing method or pressure specification. Specify seamless construction explicitly.
Match the finish to the requirement
For a process, analyser or high-purity line, state the required internal finish and cleaning specification rather than relying on a polished appearance. Where roughness is specified, include the parameter, limit and measurement method. Ra and Ry values are different measures and should not be substituted.
Confirm availability, tube size, wall thickness, finish and documentation for the exact line item. Cleaning, end protection and packaging should be included in the quotation where required.
Surface-finish and ordering reference
Download Seamless tubing: AP, BA and EP finishes PDFThe Uni-Lok reference includes both seamless and welded tubing. Use only the details that apply to the construction and product quoted by Fluidline.
Enquire about this product
Prepare a Seamless tubes: AP / BA / EP enquiry ↗Frequently asked questions
Does an EP finish set the pressure rating?
No. Pressure capability must be checked for the tube material, dimensions, temperature and connection system. EP describes a surface-finishing requirement.
