Vacuum Sausage Filler

Overview

A vacuum sausage filler meters meat emulsion, ground meat, or paste from a hopper and pumps it through a filling tube into a casing. The vacuum part of the name matters: air is drawn out of the product before and during filling, so the finished sausage has no voids, holds a consistent density, and resists discoloration and rancidity in storage. Industrial fillers of this class run continuously at outputs around 3,000 kg/h and divide the stream into portions at up to 600 pieces per minute.

The machine is built around four working groups. The Hopper Assembly holds the product. The Vane-Cell Pumping System is the metering heart that displaces a measured volume per rotation. The Vacuum System de-airs the product. The Outlet & Portioning System cuts the flow into portions and, with the linking attachment, forms a chain of twisted links. A stainless Cabinet & Frame carries everything, and a washdown Control System coordinates the servo axes.

How it works

Product is loaded into the hopper, where a slow Hopper Feed Screw keeps the throat of the pump fed without smearing or overworking the emulsion. As the rotor turns, each cell between the vanes opens at the inlet, fills with product, carries it around the bore, and is squeezed shut against the feed curve at the outlet. The volume swept per revolution is fixed by geometry, so the portion weight is set by counting rotor increments. The main Main Servo Motor (4 kW) turns the rotor through a Planetary Gearbox, and its absolute encoder lets the control resolve the rotor angle finely enough to hit a portion within roughly one gram.

When a portion target is reached, the rotor stops or the Portion Cut-Off Valve closes, the Twisting Head spins the filling tube a set number of turns to pinch a link, and the cycle repeats. Because the rotor decelerates and restarts hundreds of times per minute, the drive is sized for high dynamic torque rather than top speed.

Vane-cell pump

The Pump Rotor runs inside a precisely bored Pump Housing. Eight Vane (Cell) blades slide in radial slots in the rotor; each Vane Spring pushes its vane outward so the tip stays in contact with the bore and seals the cell. The rotor sits off-center relative to the bore, so the cell volume grows on the inlet side and shrinks toward the outlet, which is what moves the product.

Portion size is changed without swapping parts by moving the Feed Curve / Pressure Plate, the eccentric pressure plate that sets how far the vanes extend and therefore the displaced volume. A Feed Curve Actuator driven by a Stepper Motor repositions the curve from the recipe screen. The rotor runs on a stainless Pump Rotor Bearing at each end, and a hygienic Pump Shaft Seal separates the product chamber from the drive so juices cannot reach the bearings. Outlet pressure, which can reach 45 bar with stiff product, is read by the Product Pressure Sensor and used to protect the casing and hold a steady fill.

Vacuum system

Air trapped in emulsion leaves pockets that spoil slicing yield and shorten shelf life, so the product is evacuated as it enters the pump. A Rotary Vane Vacuum Pump, a rotary-vane unit with carbon-graphite vanes, pulls the Vacuum Chamber around the pump inlet down to anywhere from 50 to 950 mbar depending on the recipe. The Vacuum Solenoid Valve isolates the chamber between cycles and admits a vent so the chamber can be opened.

A Vacuum Inline Filter in the line keeps product aerosol out of the pump, and a Condensate Trap collects the liquid that the vacuum draws off. The operator reads chamber pressure on the Vacuum Gauge and trims the setpoint for the product: a fine emulsion for hot dogs needs deep vacuum, while a coarse ground product needs less so it does not lose structure.

Portioning and linking

At the discharge the product passes through the Outlet Manifold and onto the Filling Tube, over which the casing is shirred. A Casing Brake Ring holds back-tension on the casing so the fill is even and the diameter is consistent. The Twisting Head, driven by its own servo and held in a quick-change Tube Chuck, rotates the tube to twist a link between portions.

For chained product the Linking Attachment bolts on at the outlet. Its Linking Conveyor and Discharge Belt carry the linked chain away at a speed matched to the fill rate, so links form at a fixed length without bunching. Changing the link length is a recipe value, not a mechanical change.

Materials and hygiene

Every wetted part is 1.4404 (316L) or 1.4301 (304) stainless, food-grade silicone, or FDA-approved polymer such as the POM used for the Casing Brake Ring. The frame is built on an open base on stainless Swivel Castor units with Leveling Foot supports so the floor underneath can be cleaned. The Control Enclosure is an IP69K cabinet that withstands high-pressure, high-temperature washdown. Surfaces are radiused and the Drip Tray catches product, all to meet EHEDG-style hygienic design so the machine can be cleaned without disassembly.

Use and maintenance

Daily care is washdown and inspection of the Hopper Lid Seal and pump seal. The pump bearings and twisting head are fed by the Central Lubrication group, whose Lubrication Pump sends grease through a Progressive Distributor to each point on a timed cycle, so no manual greasing is needed during a shift. The vacuum pump vanes and the Vacuum Inline Filter are wear items checked weekly, and the Condensate Trap is drained each clean-down. Vane wear in the metering pump shows up as drifting portion weight; the control flags it against the Product Pressure Sensor trend, and the vanes and springs are replaced as a set. With food-grade Food-Grade Gear Oil in the gearbox and routine seal changes, a filler of this size runs for years on a single-shift line.