DIN 50135 — Drift Expanding Test for Metallic Tubes

DIN 50135:1965-08 — Prüfung metallischer Werkstoffe; Aufweitversuch an Rohren

DIN 50135 (edition 1965-08) describes a mechanical test in which a tube specimen is expanded by driving an expanding tool (drift/mandrel) into the tube end. The result is used to assess whether the tube can withstand a specified amount of expansion without cracking or other unacceptable damage.

DIN lists this document as withdrawn and indicates successor standards for current use. In practice, buyers will often still see “DIN 50135” referenced on legacy tube products, in internal work instructions, or in long-lived industry specifications.

Quick definition

What it is: A drift expanding test method for metallic tubes (a controlled expansion/compression-style mechanical test).

What it evaluates: Tube ductility and resistance to cracking during plastic expansion at the tube end.

Common output: Pass/fail against an agreed expansion requirement and a post-test visual assessment for cracking (often focused on the tube body and, when applicable, the weld area).

What This Standard Covers

DIN 50135 covers the drift expanding (Aufweitversuch) procedure for tubes made from metallic materials. The standard is used when a tube’s ability to plastically expand is a relevant quality attribute for manufacturing, assembly, or service conditions.

Because the standard is withdrawn, the exact acceptance criteria and required amount of expansion are typically defined by the governing product specification, purchase order, or delivery conditions rather than being “one-size-fits-all.”

Why This Standard Matters in Testing

Tubes are frequently expanded during fabrication and joining operations (for example, when forming, fitting, or mechanically expanding an end). The drift expanding test provides a structured way to screen for insufficient ductility, processing issues, or weld/heat-affected-zone sensitivity that can show up as cracking during expansion.

For QA/QC teams, the method is often used as a lot acceptance or process-control check that complements tensile testing and other tube technological tests.

Common Materials, Product Types, or Applications Covered

DIN 50135 is most commonly associated with metallic tube and pipe products where end expansion is relevant to fitness-for-use or manufacturing robustness.

Common product forms: Welded or seamless tubes, tube sections cut for technological testing, production samples taken from finished tube.

Common use contexts: Incoming inspection, mill test programs, qualification of tube supply, and verification programs referenced by customer or industry delivery conditions.

Common Test or Verification Workflow

In a typical drift expanding test workflow, a tube specimen is prepared to the required length and the tube end is expanded by forcing an expanding tool into the tube. The expansion continues until the specified requirement is reached or until a discontinuity (such as cracking) is observed.

Common workflow steps: Define the required expansion criterion from the governing product specification; select an appropriate drift/mandrel and support tooling for the tube size; perform the expansion on a controlled test machine; inspect the specimen after expansion; document the result and any observed cracking or other reportable conditions.

Revision sensitivity: Setup details and reporting expectations can vary depending on whether the requirement is truly DIN 50135 (legacy) or a successor document referenced by current supply specifications.

Equipment Commonly Used for This Standard

DIN 50135 typically points to a mechanical test setup capable of applying a controlled compressive force while guiding an expanding tool into the tube end.

Common equipment: A universal testing machine or compression-capable materials test frame; drift/mandrel tooling sized to the tube’s internal diameter range; tube supports/anvils or positioning fixtures to maintain alignment; basic dimensional measurement tools; guarding or shielding appropriate to the lab’s safety assessment.

Practical quoting caution: The tube size range (ID/OD, wall thickness), the required expansion criterion from the governing product standard, and any special handling for welded tubes will drive mandrel selection, fixture design, and the force capacity you actually need. If you are selecting a machine and tooling package, you can request a detailed quote based on your tube dimensions and the exact standard callout in your purchase specification.

How to Read This Designation or Revision

DIN 50135:1965-08 identifies the DIN standard number and the edition date (August 1965). DIN Media lists this document as withdrawn.

Replacement / successor documents: DIN Media indicates that DIN 50135 was replaced by DIN EN 10234:1994-01 and DIN EN ISO 8493:2004-10. When a contract, drawing, or product standard still cites DIN 50135, it is good practice to clarify whether the cited legacy designation is mandatory as-written or whether the current successor document is acceptable for compliance.

Related Standards, Methods, or Frameworks

DIN 50135 is closely associated with later European and international drift expanding test standards used in modern tube supply specifications. When testing is performed for current production, the governing product standard will typically point to the appropriate EN/ISO document rather than the withdrawn DIN designation.

If you are unsure which test document your customer or auditor expects for a particular tube product, clarifying the cited requirement early helps avoid mismatched tooling, insufficient force capacity, or nonconforming reporting.

Need help matching DIN 50135 to the right test setup?

If a legacy drawing or purchase order still calls out DIN 50135, we can help you translate that requirement into an equipment configuration (frame capacity, alignment/fixturing approach, and drift/mandrel sizing) that fits your tube dimensions and acceptance criteria—just contact our team with the tube size range and the exact wording from the specification.