Overhead Stirrer

What Is an Overhead Stirrer?

An overhead stirrer (also called an electric overhead stirrer, laboratory stirrer, or overhead mixer) is a motor-driven mixing device mounted above the sample vessel. Unlike magnetic stirrers that rely on a rotating magnetic field for small volumes, an overhead stirrer uses a direct-drive motor connected to a stainless steel stirring shaft and impeller. This design delivers significantly higher torque, making overhead stirrers the standard choice for high-viscosity liquids, large-volume samples (from 0.5 L to 50 L or more), and applications requiring precise, reproducible mixing.

Hawach overhead stirrers are widely used in pharmaceutical R&D, chemical synthesis, cosmetics formulation, food processing, biotech, and quality control laboratories – anywhere that magnetic stirrers stall or fail to provide adequate mixing.

Why upgrade from a magnetic stirrer? Magnetic stirrers work well for small, low-viscosity samples. When you need to mix thick pastes, emulsions, polymer solutions, or large batches, an overhead stirrer provides the torque and control that magnetic bars cannot deliver.

Overhead Stirrer vs Magnetic Stirrer – Which One Do You Need?

Selection tip: If your application involves high-viscosity samples, volumes over 2 L, or requires stable mixing over extended periods, choose an overhead stirrer. For routine mixing of small, low-viscosity solutions, a magnetic stirrer may be sufficient.

Quick Selection Guide – Which Overhead Stirrer Fits Your Workflow?

Not sure which model fits your application? Email info@hawach.com with your sample type, viscosity, and volume – our team will recommend the right configuration.

Applications of Overhead Stirrers

Key Features of Hawach Overhead Stirrers

Permanent magnet DC motor with force-enhancing function – Stable speed output, continuous stepless speed regulation, low noise (<40 dB)

Wide speed range (200-3000 RPM) – Covers gentle to vigorous mixing for diverse applications

Digital speed display models – Real-time speed readout, ±20 rpm or ±1 rpm accuracy depending on model; direct speed setting via instrument buttons on high-precision models (18111005, 18111008)

304 stainless steel stirring shaft – Corrosion-resistant, durable, easy to clean; suitable for aqueous and organic solvents

Remote control box – Allows operation away from the worktable, ideal for fume hoods and biosafety cabinets

Programmable timer – 0-120 min or 0-9999 min options; enables unattended operation for extended mixing protocols

Multiple power options – 40 W, 60 W, 100 W, 200 W, 300 W to match torque requirements

Multi-position models – Process 4 or 6 samples simultaneously, significantly increasing laboratory throughput

Low noise operation (<40 dB) – Quiet enough for open-bench laboratories

Technical Specifications – Overhead Stirrer

Ordering Information – Complete SKU List

Single-Position Overhead Stirrers

Multi-Position Overhead Stirrers (4 or 6 units)

Selection tip: For routine QC and simple mixing tasks, analog models (18111001, 18111003, 18111006) offer cost-effective performance. For applications requiring precise speed control and documentation, choose digital models. For extended mixing protocols (e.g., overnight reactions), select models with 0-9999 min timer (18111005, 18111008).

Why Procurement Teams Choose Hawach Overhead Stirrers

• Workflow-compatible with major brands -Designed for applications commonly performed with IKA, Heidolph, and VWR overhead stirrers. Use the same vessel sizes, impeller designs, and speed ranges – no method revalidation required for most applications.
• Cost-effective alternative -Competitive pricing compared to premium brands without compromising motor torque, speed stability, or noise performance.
• Multi-position models -Process 4 or 6 samples simultaneously, dramatically increasing laboratory throughput for high-volume QC and R&D workflows.
• Remote control box -Operate the stirrer outside fume hoods or biosafety cabinets; control box can be placed on the bench while the motor runs inside the enclosure.
• Wide speed range (200-3000 RPM) -Covers gentle mixing (e.g., cell culture media) to vigorous stirring (e.g., high-viscosity polymer solutions).
• 304 stainless steel shaft -Corrosion-resistant, compatible with aqueous solutions, organic solvents, and mild acids/bases.
• Low noise (<40 dB) -Quiet operation suitable for open-bench laboratories.
• Multiple motor power options -40 W for routine mixing; 100 W, 200 W, 300 W for high-viscosity or large-volume applications.
• Programmable timer -Extended timer options (up to 9999 min) for unattended overnight mixing.
• In-stock -Standard models ship within 3-5 business days. Custom configurations available for volume orders.
• OEM & private label -Custom branding, packaging, and bulk supply for distributors and volume buyers.
• Evaluation units available -For qualified laboratories and distributors.

How to Choose an Overhead Stirrer – Selection Guide for Laboratory Managers

Step 1: Choose by sample viscosity and volume

Step 2: Choose by throughput

Step 3: Choose by control requirements

Industries Served

• Pharmaceutical R&D & QC laboratories
• Chemical synthesis & manufacturing
• Cosmetics & personal care formulation
• Food & beverage processing
• Biotechnology & life sciences research
• Paints, inks, coatings manufacturing
• University research & teaching laboratories
• Environmental testing laboratories

Frequently Asked Questions