Heidolph Hei-TORQUE Core Overhead Stirrer Base Unit

Overview

The Heidolph Hei-TORQUE Core Overhead Stirrer Base Unit is a compact, high-performance laboratory stirrer engineered for precision mixing and dispersion tasks in R&D, quality control, and production support environments. Designed according to the principles of mechanical torque transmission and rotational dynamics, it delivers consistent shear input across a wide viscosity range—from low-viscosity aqueous solutions to highly structured non-Newtonian fluids—using a robust brushless DC motor coupled to a single-stage planetary gear system. Its core architecture prioritizes thermal stability, mechanical repeatability, and operator safety, making it suitable for extended unattended operation in regulated laboratories. Unlike magnetic stirrers, the Hei-TORQUE Core employs top-driven mechanical agitation, enabling reliable handling of large-volume vessels (up to 25 L), viscous media, and heterogeneous suspensions where magnetic coupling would fail.

Key Features

• High-torque output of 40 N·cm at low speeds, maintaining stable rotation even under load-induced deceleration
• Wide speed range from 20 to 2000 rpm, digitally controlled via intuitive rotary encoder with tactile confirmation for start/stop activation
• Integrated timer function supporting programmable run durations up to 99 hours, 59 minutes, and 59 seconds
• Dedicated “Max” mode for transient high-speed bursts (2000 rpm) without manual reconfiguration—ideal for rapid homogenization or deagglomeration
• Real-time electronic speed display on a 2-inch monochrome LCD, resistant to chemical fogging and ambient light interference
• IP42-rated enclosure (per DIN EN 60529) providing protection against solid objects ≥1 mm and vertically falling water droplets—suitable for standard fume hood and benchtop use
• Thermal overload protection triggers automatic shutdown if internal motor temperature exceeds safe operational thresholds
• Single-stage planetary gearbox optimized for minimal backlash and high torque transfer efficiency, with no user-serviceable lubrication points
• Compact footprint (70 × 281 × 195 mm) and lightweight design (2.3 kg) facilitate integration into modular lab setups or mobile workstations

Sample Compatibility & Compliance

The Hei-TORQUE Core accommodates standard laboratory stirrer shafts up to 10.5 mm in diameter, supporting common impeller types including paddle, propeller, anchor, and helical ribbons. It is validated for use with glass, stainless steel, and polymer reaction vessels ranging from 500 mL to 25 L capacity. While not intrinsically rated for explosive atmospheres, its electrical design complies with IEC 61010-1:2010 for safety in laboratory equipment. The unit operates within environmental specifications aligned with ISO/IEC 17025:2017 clause 5.3 (environmental conditions), and its digital control architecture supports audit-ready operation when deployed in GLP or GMP contexts—particularly when paired with external data loggers for traceable speed/timing records.

Software & Data Management

As a standalone base unit, the Hei-TORQUE Core does not include embedded connectivity (e.g., USB, RS-232, or Ethernet). However, its analog-compatible speed output signal (0–10 V) permits integration with third-party process controllers, SCADA systems, or programmable logic controllers (PLCs) for centralized monitoring. For regulatory-compliant environments, users may implement manual logbook entries or integrate the device into validated electronic lab notebook (ELN) workflows. Though lacking native 21 CFR Part 11 compliance features such as electronic signatures or audit trails, its deterministic behavior and mechanical reproducibility support qualification protocols under FDA guidance for ancillary mixing equipment used in pharmaceutical manufacturing.

Applications

• Preparation of polymer solutions, emulsions, and colloidal dispersions requiring controlled shear history
• Cell culture media conditioning and buffer blending in bioprocessing labs
• Viscosity benchmarking of industrial coatings, adhesives, and cosmetic formulations
• Accelerated stability testing involving long-duration stirring under defined temperature/humidity conditions
• Reaction mixture homogenization prior to analytical sampling (e.g., HPLC, GC, or titration)
• Supporting ASTM D2196 (viscosity of paints) and ISO 2557-2 (plasticized PVC pastes) test methods through repeatable agitation profiles

FAQ

Is the Hei-TORQUE Core compatible with external temperature control systems?

Yes—it can be operated alongside jacketed vessels and circulating chillers; however, temperature regulation is managed externally, as the unit itself does not incorporate heating or cooling elements.
Can it be used in inert atmosphere gloveboxes?

Provided physical access and power routing are available, yes—the IP42 rating and absence of vented motor housings allow safe operation in nitrogen- or argon-purged enclosures.
Does it support continuous duty cycle at maximum torque?

Continuous operation at 40 N·cm is thermally limited; sustained high-load use requires intermittent duty cycles or active cooling of the vessel to prevent motor overheating.
What maintenance is required?

No routine lubrication or calibration is needed—the sealed gearbox and brushless motor ensure maintenance-free operation over typical laboratory service life (≥5 years under normal use).
Is firmware upgrade capability available?

No—this is a fixed-function hardware platform without field-upgradable firmware; functionality is defined at manufacture and remains invariant throughout product lifetime.