ISO 34-2 is an ISO test method used to determine the tear strength of vulcanized or thermoplastic rubber using small “Delft” test pieces. It is commonly selected when only a limited amount of material is available, or when evaluating small finished rubber products where standard-sized specimens are difficult to obtain.
If you need help confirming whether ISO 34-2 is the right tear method for your sample size, thickness range, or product geometry, talk with our team about your application.
ISO 34-2:2022 — Rubber, vulcanized or thermoplastic — Determination of tear strength — Part 2: Small (Delft) test pieces
ISO 34-2 is part of the ISO 34 series for tear strength testing of rubber. Part 2 focuses specifically on small Delft specimens, which can be advantageous for limited material availability and for certain finished-part evaluations.
Document type: Test method (International Standard).
Quick Definition
ISO 34-2 describes a laboratory method for measuring the tear strength of vulcanized or thermoplastic rubber using small Delft test pieces pulled in tension until tearing occurs.
Typical output: Tear strength value derived from the measured force at tear and the relevant specimen dimensions (as defined in the cited edition).
What This Standard Covers
This standard covers tear strength testing of small (Delft) rubber test pieces, including the general approach to preparing the specimen shape, applying a controlled tensile load, and reporting tear strength results.
Material scope: Vulcanized rubber and thermoplastic rubber.
Specimen scope: Small Delft test pieces (used when standard tear specimens may be impractical due to limited material or small product size).
Why This Standard Matters in Testing
Tear resistance is often used as a comparative durability indicator for rubber compounds and products that may experience cut growth, nick propagation, or edge tearing in service. ISO 34-2 is especially useful when sample size constraints make larger tear specimens difficult to produce.
Practical caution: Results from Delft test pieces are not necessarily interchangeable with tear results from other ISO 34 specimen types, so purchasing and QA decisions should be tied to the specific part of ISO 34 cited in customer or internal requirements.
Common Materials, Product Types, or Applications Covered
ISO 34-2 is commonly applied to rubber materials and small rubber components where tear performance is a relevant risk or acceptance criterion.
- Elastomer compound screening and formulation comparisons
- Small molded rubber parts and seals where specimen extraction is limited
- Thin sections or small cut samples taken from finished goods for investigative testing
Common Test or Verification Workflow
ISO 34-2 is typically used as part of a lab workflow to compare materials, qualify compound changes, or document tear performance for supplier/customer requirements.
Common workflows: Incoming material checks, compound change validation, process troubleshooting, product performance benchmarking, customer specification reporting.
What to align before testing: The exact cited edition, specimen preparation approach (including how Delft specimens are produced), conditioning requirements, and reporting rules required by the program or customer.
Equipment Commonly Used for This Standard
ISO 34-2 tear testing is typically performed on a tensile/universal testing system configured for elastomers, with tooling that supports consistent gripping and repeatable specimen preparation.
Common equipment: Universal testing machine (UTM) or tensile tester; appropriate load cell capacity for elastomers; grips suitable for small rubber specimens; specimen cutting die(s) for Delft test pieces; thickness measurement tools for specimen dimension inputs; basic lab conditioning capability when required by the test program.
If you are selecting a tensile frame capacity, grip style, or specimen preparation tooling for ISO 34-2 work, you can request a detailed quote for a configuration matched to your sample size and expected tear force range.
How to Read This Designation or Revision
The designation “ISO 34-2” identifies Part 2 of the ISO 34 tear strength series (the part that uses small Delft test pieces). When a year is included (for example, “ISO 34-2:2022”), it indicates the published edition being referenced.
Revision sensitivity: Test setup and reporting details can vary by edition. For purchasing fixtures or writing procedures, always match the equipment setup to the exact edition cited in your customer or internal requirement.
Related Standards, Methods, or Frameworks
ISO 34-2 is part of the ISO 34 family. Other parts may be referenced when different specimen shapes are required, or when historical data was generated under a different ISO 34 method.
Related in the ISO 34 series: ISO 34-1 (tear strength using trouser, angle, and crescent test pieces).
Get help configuring ISO 34-2 tear testing
For help choosing a tensile tester, grips, and Delft specimen tooling that fit your rubber type and force range, ask for a quote and include the edition you are working to (for example, ISO 34-2:2022) along with specimen thickness and expected tear strength levels.