500 Liters Sigma Mixer

The 500 liters Sigma Mixer, also known as a Sigma Blade Kneader or Z-Blade Mixer, is a robust, heavy-duty industrial mixing machine engineered for the intensive kneading and blending of highly viscous materials. This equipment excels in applications requiring uniform dispersion and thorough homogenization, making it indispensable in industries such as rubber processing, silicone compounding, adhesives production, pharmaceuticals, food manufacturing (e.g., chewing gum and pastes), chemicals, pigments, inks, and plastics.

Sigma Mixer Machine Video

Key Design and Construction Features

At the heart of the 500L Sigma Mixer is its durable, heavy-gauge construction, typically fabricated from mild steel or high-grade stainless steel to withstand rigorous operation and corrosive environments. The mixing trough measures approximately 38″ x 39″ x 39″ (about 965mm x 990mm x 990mm), providing a total vessel capacity of 500 liters. The trough is often jacketed with carbon steel for precise temperature control, supporting electric heating, steam heating, hot oil circulation, or water cooling to maintain process temperatures from ambient to elevated levels.

The mixer’s core components include:

• Blades: Two counter-rotating Z- or sigma blades, precision-machined for minimal gaps (under 3mm) to prevent material buildup. Blades are driven by a robust gearbox and variable-speed motor setup, ensuring torque delivery for dense loads.

• Drive System: Equipped with a high-torque main motor rated at 30-45 kW (e.g., 37 kW standard), paired with a secondary screw discharge motor of 7.5 kW. Power consumption ranges from 45-75 kW per cubic meter of material, supporting 3-phase operation at 380-480V.

• Lid and Safety: A hydraulic or manual tilt-opening lid with safety interlocks, viewing windows, and optional vacuum ports for degassing. Dust-free covers enhance operator safety and containment.

Operational Capabilities and Discharge Mechanisms

Operation is semi-automatic or fully automated via PLC controls, with intuitive panels for speed adjustment, timer settings, and temperature monitoring. Blades rotate at differential speeds (typically 30-40 RPM for one blade and 20-25 RPM for the other) to create a cascading effect that folds, kneads, and shears materials against the trough walls. This design is particularly effective for non-free-flowing substances like silicone rubber, sealants, putty, electrode pastes, and carbon compounds, ensuring bubble-free, streak-free results.

Discharge options include:

• Hydraulic Tilt Discharge: The entire trough tilts up to 120-150° for gravity unloading, ideal for sticky formulations.

• Screw Extruder Discharge: A bottom-mounted auger (driven by the auxiliary motor) forces material out through a valve, minimizing waste and enabling continuous processing.

Heating/cooling jackets cover the sides and bottom, with circulation ports for uniform heat transfer. Vacuum integration is available for moisture removal or volatile extraction, and the system complies with CE, ISO 9001, SGS, and GOST standards for global safety and quality assurance.

Applications and Performance Benefits

This mixer shines in high-viscosity scenarios where conventional agitators fail, such as:

• Rubber and Plastics: Kneading silicone rubber, BMC/CMC compounds, or hot-melt adhesives.

• Food and Confectionery: Blending chewing gum bases, sugar pastes, or fruit pulps (food-grade SS316 variants with mirror-polished finishes).

• Chemicals and Paints: Dispersing pigments, inks, dyes, or viscous resins.

• Other: Battery compounds, toothpaste, clays, and electrode pastes.

Performance highlights include energy-efficient operation (30% lower consumption in advanced models), easy cleaning via CIP (Clean-In-Place) designs, and scalability—part of a range from 25L lab units to 5,000L production models. With a 1-year warranty and customizable options like variable frequency drives or ATEX explosion-proof ratings, the 500L Sigma Mixer delivers reliable, low-maintenance performance for demanding production lines, processing up to 500-1,000 kg per batch at rates of 60-1000 kg/hour depending on material density.

Salient Features of Sigma Mixer Machine

• Available in Stainless Steel 316, Stainless Steel 304 and Mild Steel materials.

• Stainless Steel polish to matt & mirror finish as per customer’s requirements.

• Mild Steel finish with one coat of red oxide and two coats of epoxy paint.

• Discharge option of hand wheel operated (manual) or hydraulic operated (automatic) offered.

• Jacket for heating or cooling application can be offered.

• Mineral wool insulation with cladding on jacket.

• Tangential designed ‘Z’ blades offered for uniform mixing.

• PTFE made shaft sealing provided for food grade compatibility.

• Minimum gap between trough inner shell & blades removes possibility of sticking product.

• On demand Spray system, vacuum system

Optional Features/Accessories of Sigma Mixer

• Liquid Spray System

• Vacuum System

• Blades Cooling Arrangement

• Screw System

• Automatic Valve Discharge System

Process Operation of Sigma Mixer Machine

In Sigma mixer tangential action of mixing and kneading obtained by ‘Z’ type (SIGMA) shaped kneading blades, which rotates very accurately at different speed towards each other causing product to be transferred from one end to another end. Discharge of the finished product is achieved by tilting the container or through the valves at the bottom or by means of an extrusion screw beside the container.

The mixing action is a combination of bulk movement, stretching, folding, dividing, and recombining of the material. The shearing & tearing action of the material against blades and the side walls causes size reduction of the solids. After the time period required for sterilizing the batch has elapsed, the heating circuit shuts of the pneumatics damper (exhaust) opens and cooling operation commences.

In the tangential design, the blades rotate in the trough meeting tangentially. The front blade generally rotates faster than the rear blade usually in the ratio of 3:2. Tangential blades are generally used for material of higher viscosities such as adhesives, rubber compounds, flush colors, dyes, and pigments.

In the overlapping design, the blades overlap above the saddle of the container. Due to the overlapping action, it is necessary that the relative position of the two blades is unchanged, and as a result, both the blades rotate at the same speed. Materials that flow freely or creep down into the blades are mixed using the overlapping blade action. This design offers a faster interchange of material from one blade compartment of the mixer to the other. Overlapping blade action is used for materials of lighter viscosities such as carbon pastes, clay coating, creams, and ointments. The overlapping blade produces a lower kneading and shearing compared to the tangential blade action.

Technical Specification of 500 Liters Sigma Mixer

* Power voltage can be adjusted as per customer’s domestic power voltage requirements.
* Rights of technical improvements & modification reserved.
* Illustrations & dimensions are shown for information purpose only.