Non-Rotor Rubber Vulcanizer: Specifications & Testing Principles

Applicable Standards:

• ASTM D5289: Standard Test Method for Rubber Property—Vulcanization Using Rotorless Cure Meters.
• ISO 6502: Rubber—Measurement of Vulcanization Characteristics with Rotorless Curemeters.
• GB/T 16584: Chinese National Standard equivalent to ISO 6502.

Main Parameters (Table 1):

Working Principle:
The tester operates by sealing a rubber specimen in a two-part mold cavity. One section oscillates with a small-amplitude motion (angular or linear), inducing shear strain, while the other remains stationary. A transducer measures the torque response, which correlates with the material’s viscoelastic changes during curing. Key metrics derived include:

• ML (Minimum Torque): Indicates viscosity before curing.
• MH (Maximum Torque): Reflects fully cured stiffness.
• ts2/t10: Scorch time (onset of vulcanization).
• t90: Optimal cure time for process efficiency.

Test Principle:
The test simulates industrial curing conditions by heating the specimen to a predefined temperature. As crosslinking begins, the torque increases due to rising shear modulus. The instrument plots torque vs. time curves, enabling calculation of cure rates and activation energy. Advanced models incorporate temperature compensation algorithms to minimize thermal gradients, ensuring repeatability. By comparing torque increments (e.g., 90% of MH), manufacturers optimize formulations for specific applications, such as high-rebound soles or oil-resistant seals.

Applications:

• Quality Control: Verify batch consistency in compound production.
• R&D: Accelerate formulation development by screening accelerators and fillers.
• Failure Analysis: Identify premature curing or incomplete crosslinking via torque signature deviations.

This equipment’s precision and compliance with international standards make it indispensable for modern rubber labs, ensuring products meet durability and safety requirements.