Taring line for Potatoes

A taring line developed by RMA-Techniek for taring and inspecting potatoes.

Weighing Bunker

The sample is dropped into the weighing bunker via the supply belts. The weighing bunker is equipped with a weighing container with two valves at the bottom and a screen.

After the sample has been weighed, a choice must be made whether the sample is unloaded to the left of the right side. On the left side, the sample is unloaded onto an elevator belt and continues its way over the automatic tare line. On the right side, the sample is unloaded into a basket or crate and then processed in the manual inspection room.

Soil Cleaner

The sample is unloaded onto a belt from the weighing bunker. The soil cleaner is equipped with an elevator belt and a roller bed.

The elevating belt discharges the sample onto the roller bed where the potatoes are turned by means of rollers. Due to the rotating movement, the loose soil that is still present in the sample will fall between the rollers on a discharge belt.

After 'turning' the potatoes, the head of the elevator belt is lifted slightly by means of pneumatic cylinders to make room for the rolling bed. The roller bed in turn is tilted by means of pneumatic cylinders to discharge the sample onto the stone separator.

Stone Separator

The sample is discharged into the stone separator from the soil cleaner. The stone separator is equipped with a bar belt and a discharge belt.

The stone separator consists of a large container with water. The sample is therefore released into the water immediately. A current is created in the water by means of a rotating screw. This flow pushes the potatoes towards the delivery bar. Any stones in the sample float less than the potatoes and are less susceptible to the current. These drop down on the discharge conveyor.

The discharge belt discharges the stones on the same discharge belt as the loose soil. The output belt discharges the sample in a washer.

Washer

The sample is discharged at the top into the washer. The washer is equipped with a washing disc. As soon as the potatoes are in the washer, the machine starts and the bottom, which consists of a washing disc, starts to rotate. The potatoes will be thrown around in the drum and the rubbing against each other and rinsing with water will remove the dirt from the potatoes. After a set time, the washer will eject the potatoes through a valve on an elevator belt towards the dosing unit.

Dosing Unit

The sample is unloaded onto the dosing belt via a conveyor belt. The dosing unit is equipped with a conveyor belt and a vibrating chute.

The dosing belt discharges the potatoes on the vibrating chute in a dosed manner. The vibrating trough consists of three tracks, so that the potatoes are singled, in 3 tracks, unloaded onto the belt of the 3D camera.

3D camera

The sample is unloaded via the dosing unit onto the belt of the 3D camera. The 3D camera is equipped with a conveyor belt and a 3D camera in a closed hood.

The sample is transported under the 3D camera by means of the conveyor belt. The 3D camera can measure the length, width, and height of the potatoes without stopping the conveyor belt. This information is collected per sample and made available online. After the 3D camera, the sample is unloaded onto a conveyor belt.

Roller Sorters

The sample is unloaded via a conveyor belt onto the roll sorter. The roll sorter is equipped with a roll bed and a weighing bucket.

The potatoes pass directly from the elevator over the roller bed. The roller bed ensures that the potatoes of 40 mm and smaller are rotated downwards in between the rollers and end up in a weighing bin. After weighing the potatoes of 40mm and smaller, this in turn discharges the potatoes onto a conveyor belt. The potatoes larger than 40mm are unloaded in a weighing bucket after the rolling bed.

Salt bath

The sample is discharged into the salt bath via an elevator belt. The salt bath is equipped with a separate tank, an outfeed belt, and a weighing bucket.

The salt bath consists of a plastic container full of salt water. The sample is then discharged directly into the water by the elevator belt. Due to the salt content of the water, the potatoes with a low dry matter content float. The floating potatoes float into a collecting tank by means of a light current.

The other potatoes sink on the export bar and are rinsed with fresh water on the way to inspection table 1.

When the sunken potatoes have been removed, the collecting tray with the floating potatoes is tilted by means of pneumatic cylinders. The water is simultaneously pumped away to the separate tank so that the floating potatoes also end up on the outfeed belt. By means of pneumatic cylinders, the hopper after the outfeed belt is moved to a different position so that the floats are unloaded into a weighing bucket. After weighing the sample, the weighing container unloads onto the discharge belt.

The separate tank is used to store the water from the salt bath when the salt bath is being pumped out. The salt is also added to the separate tank to make/maintain the salt content. When the water is pumped back from the tank to the salt bath, the salinity is measured by means of a salt meter.

Inspection Table 1

The sample is unloaded from the salt bath onto the inspection table. The inspection table is equipped with a reading belt, 2 weighing buckets, and 2 pushbuttons to control the belt and the weighing buckets.

When the potatoes are unloaded on the inspection belt, the inspector can turn the belt as far as he wants. Here the potatoes are assessed for external defects. The inspector can pick out the defects and put them in the weighing buckets. As soon as the judge presses the appropriate button, the weight is saved, and the weighing buckets are tilted empty again on the inspection belt by means of pneumatic cylinders. The sample is discharged into the peeler immediately.

Peeler

The sample is discharged at the top into the peeler. The peeler is equipped with a peeling disc and an anti-foam tank.

As soon as the potatoes are in the peeler, the machine starts and the bottom, which consists of a peeling disc, starts to rotate. The potatoes will be swung around in the drum and sanding along the disc and each other will remove the skin from the potato. The dirt and loose skins of the potatoes will be washed away by means of water. After a set time, the peeler will eject the potatoes onto an elevator belt through a valve.

Automatic Underwater Weigher

The sample is unloaded via an elevator belt into the basket of the automatic underwater weigher. The automatic underwater weigher consists of a basket for the potatoes and a container with water.

When the potatoes are in the basket of the underwater weigher, the sample is weighed. After saving this data, the basket sinks into the water by means of a pneumatic cylinder. When the basket is completely submerged, it is weighed again, and the data is stored. With this data, the dry matter content of the sample is determined. The basket is then pulled up again and tilted empty on inspection table 2 by means of pneumatic cylinders.

Inspection table 2

The sample is unloaded onto the inspection belt by the automatic underwater weigher. Inspection table 2 is equipped with a reading belt, a plateau with 5 bins, and a 15” screen from Siemens.

When the potatoes are unloaded onto the inspection belt, the inspector can operate the belt via the Siemens screen. Here the sample can be internally assessed for defects by the inspector. The defects can be collected in the bins. The details of the defects are entered manually via a screen. When the sample is completed, the judge empties the bins back onto the inspection belt. By means of a manual selection valve, the sample can be (partially) discharged on a discharge belt or in the automatic deep-fat fryer.

Automatic fryer

The sample is unloaded into the funnel of the elevator belt from the inspection belt or manually. The automatic fryer is equipped with a conveyor belt for the infeed of potatoes, a fry cutter, a fryer, 3 vibrating chutes, an extraction, and a 7” screen for the control.

When the potatoes have been unloaded in the hopper, the potatoes are transported upwards by 2 by means of the elevator belt to a vibrating trough with 2 tracks. After the vibrating chute, the potatoes come out in the fry cutter, where a fry is cut from the core of each potato. The cutting waste falls and is discharged directly to the discharge belt.

The loose fries end up on a vibrating chute with 2 tracks. Here the fries are also misted with water by means of a nozzle. At the end of the vibrating chute, the fries are collected in a collecting tray.

When enough fries have been collected in the collecting tray, the tray is lifted upwards by means of a pneumatic cylinder. By means of a servo motor and a linear guide, the collecting tray is raised above 1 of the 2 frying baskets. When the collecting container is in the correct position, the fries are unloaded.

When the fries are in the frying basket, the basket sinks into the fat by means of a pneumatic cylinder. When the fries are cooked, the basket is tilted back above the fat to drain. When most of the fat has run out, the basket is tilted further empty on a dosing vibrator that unloads the fries onto a platform at the rear of the automatic fryer.

The automatic taring line consists of the following machines: