Views: 21 Author: Site Editor Publish Time: 2026-03-18 Origin: Site
This week at the Karvil Machinery plant, our team is doing final crating on a custom-built 1000L Vacuum Kneader (Sigma Mixer). This unit just passed its Factory Acceptance Test (FAT) and is currently being loaded for sea freight to a chemical plant in Turkey, where it will be used exclusively for manufacturing RTV-2 thermal conductive silicone.
If you've ever processed high-viscosity silicone compounds like RTV-2, you know the two biggest headaches on the production floor:
Trapped air bubbles ruining the final product.
Getting the sticky material out of the tank without wasting hours on manual scraping.
We configured this 1000L kneader specifically to tackle those two exact problems.

Here is a quick breakdown of what makes this unit work for heavy silicone pastes:
Heavy-Duty Sigma Blades: The core of the machine. The two Z-type blades rotate at different speeds toward each other, providing the massive shearing force required to fold and blend the thick silicone base with thermal conductive fillers.
Deep Vacuum Degassing: RTV-2 must be completely void-free. We built the mixing chamber with high-integrity vacuum seals. While the blades knead the material, the vacuum pump pulls out all the entrapped air and moisture, ensuring a smooth, bubble-free batch.
Hydraulic Tilting Discharge: Instead of using bottom valves (which are notorious for clogging when dealing with sticky silicone), we equipped this mixer with a hydraulic tilt system. The entire 1000L cylinder tilts forward up to 100 degrees, allowing the heavy paste to simply slide out into the receiving vessel using gravity.
Electric Heating & PLC: Temperature control is handled via an integrated electric heating jacket. To keep batch quality consistent across different shifts, everything—from blade speed and heating temperature to vacuum pressure—is wired into a centralized Siemens PLC touchscreen. The operator just selects the recipe program, and the machine does the rest.

Capacity: 1000 Liters
Blade Type: Z-Blade (Sigma)
Discharge: Hydraulic Cylinder Tilt
Heating: Electric Jacket
Control: PLC Touch Panel
Contact Parts: Stainless Steel

The machine is fully wired, tested, and wrapped. It’s always satisfying to see a heavy piece of equipment leave the floor knowing it’s going to solve a massive bottleneck for the client.
Need to upgrade your mixing process for high-viscosity sealants, adhesives, or silicones? Drop our engineering team a message to discuss your material requirements.
info@karvil.com
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Looking for a mixing equipment manufacturer that understands your process, not just your product specifications?At Karvil Machinery, we believe the right mixing solution starts with understanding what our customers need to achieve.From high-viscosity materials that require powerful kneading to bulk