UP-5008 High-Precision Rotorless Moving Die Rheometer MDR with 60℃ — 300℃ Temperature Control Range and 0.30% Torque Precision

The Rotorless Moving Die Rheometer (MDR), also called a rotorless curemeter, is the industry-standard instrument for measuring the vulcanization characteristics of rubber compounds. It records the complete cure curve in real time and reports scorch time (ts1, ts2), cure times (t10–t90), minimum and maximum torque (ML, MH) and cure rate indices (Vc1, Vc2) — giving compounders and QC labs a reliable basis for formulation development, process setting and batch release.

Unlike an oscillating-disc rheometer (ODR), the MDR uses a sealed, rotorless die cavity. With no embedded rotor to heat, the specimen reaches test temperature faster and more uniformly, temperature recovery after loading is short, and cured samples are easier to remove. The result is excellent repeatability and reproducible cure data from batch to batch and from lab to lab.

• ASTM D5289 — Standard Test Method for Rubber Property — Vulcanization Using Rotorless Cure Meters (current edition)
• ISO 6502-3:2023 — Rubber — Measurement of vulcanization characteristics using curemeters — Part 3: Rotorless curemeter (general guidance: ISO 6502-1)

An uncured rubber specimen (typically 4–5 cm³, cut with a volumetric sample cutter) is placed between two heated dies forming a sealed, nearly closed cavity, and held at the set test temperature. The lower die oscillates through a small sinusoidal angular arc (standard ±0.5°, optional ±1° or ±3°) at 1.67 Hz (100 cpm), applying a defined oscillatory shear strain to the compound.

The torque transmitted to the stationary die is measured by a high-resolution load cell and recorded as a function of time. As the compound warms and softens, torque falls to its minimum ML (compound viscosity). Once crosslinking starts, torque rises through the scorch point to a plateau or maximum MH (crosslink density / cured stiffness). Compounds prone to reversion show a torque drop after the peak. The resulting torque–time curve (cure curve), together with the temperature curve, is displayed live and stored automatically; its shape depends on the test temperature and on the compound's formulation.

• Compound development: evaluating cure packages, accelerators, fillers and anti-scorch agents
• Batch-to-batch QC and release testing of mixed rubber compounds
• Setting press cure times for compression, transfer and injection molding; avoiding under-cure and over-cure
• Tyres, seals & gaskets, hoses & belts, vibration mounts, footwear, wire & cable compounds
• Incoming material inspection, supplier qualification and third-party test laboratories

A stable single-phase 220 V / 50 Hz supply and clean compressed air at 0.5–0.65 MPa are required; the user supplies an 8 mm OD air tube. Use protective polyester/nylon film and a constant-volume specimen cutter for repeatable results. Allow the dies to stabilise at the set temperature before starting a test.