Weigh Feeder

A weigh feeder is conveying and weighing at the same time

We work with you to optimise the operation of your plant and the monitoring of your product flow.

Place your request for a quotation now and we will be pleased to give you individual advice on your weigh feeder application.

Dosierbandwaage Förderband mit Waage Durchflussmessung

Immediate advice: +49 (0) 29 61 – 96 56 86

Schlösser GmbH

Styromagnesit

CLAAS

The added value to you

Universal

Measures almost all the bulk goods in your process

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Individual

We adapt the dimensions of the conveyor to your application.

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Fully tested

The weigh feeders are factory (pre)calibrated

Precise

High repeatability and accuracy

Why is a weigh feeder the right choice for my plant?

Dosierbandwaage für Mischfutter Praxisbeispiel

With the benefit of our many years of experience we help you to select the best Flow- measurement system for your plant.

Place your request for an offer now and we will be pleased to help you:

+49 (0) 29 61 – 96 56 86

You are probably familiar with the following situation:

You need a sturdy solid flow measuring system for flow rates of 200 kg/h to 1,000 t/h.

Your product must be measured and conveyed across a horizontal distance.

You want to monitor and / or mix a continuously product flow or to load silo trucks.

The weighing system should be reliable and offer good accuracy.

The ideal solution:

The primary basic function of a belt conveyor is to ensure the safe transport of bulk products.

The criteria for the design of the conveyor, with respect to the optimum transport function therefore do not often match the requirements of the weighing technology.

We match the weighing technology factors with the technical conveying parameters and in this way create the optimum solution for maintenance-free conveying and high weighing precision.

Each weigh feeder is adjusted individually to the specific product and the application with respect to the belt speed and the belt material.

If required, Hense Wägetechnik also offers an individual system for batching or “Master / Slave” control.

Upon request, we will gladly send you a series of information about our products, starting with the access to our data sheets.

How does the weigh feeder work?

A weighing belt usually consists of a belt conveyor with a driving drum and a tail drum.

The belt is pulled by the drive and guided over rollers or supporting stations. Depending on the product, the supporting stations can be designed „troughed“ or flat.

For the weighing process one or more supporting stations are mounted on a weigh frame beneath the belt. The belt’s own weight can be “tared” to zero in the belt weigher electronic.

In practice, belt weight and belt tension are not constant and the ratio between the fluctuations of the belt’s own weight and the material to be measured is crucial in determining the measurement accuracy of a weighing belt. Where flow rates are low, the speed of the conveyor is greatly reduced.

A flat belt without braces and carriers offers higher precision of measurement than a troughed belt.

The flow rate of the belt conveyor is the product of the belt load (kg/m) and the belt speed (m/s).

The speed of belt is measured by high-precision rotary encoders. These have a typical nominal frequency of 500 to 1000 pulses/rotation. The high frequency makes it possible to link the transport speed precisely with the weight. The rotary encoder is mounted on the tail drum of the belt conveyor.

The weight signal and the speed pulses are transferred by means of shielded cables to the belt weigher electronic. This multiplies the speed with the weight signal and immediately displays the flow rate (t/h), the absolute weight (t) and other relevant parameters.

All Hense electronics units are housed in a high-quality IP67 stainless steel housing.

Depending on the type of electronics, the menu language can be adjusted. All typical interfaces, such as Ethernet, Profibus, Profinet, Modbus TCP or 4 – 20 mA can be supplied on requested.

Almost all the electronics units are also approved for the Russian and American markets.

Technical data

Grain size range:
0 – 250 mm

Centre distance:
1.3 – 6 m

Belt widths:
400 – 1,400 mm

Belt speed:
0.01 – 2 m/s

Weight sensors:
Stainless steel / IP68 / C3

System accuracy:
0.5 – 2%

Reproducibility:
+/- 0.1%

Electronics

Display:
Colour graphic display
kg/h and t/h, kg and t absolute,
trend display

Supply:
110 – 240 VAC / 12 – 30 VDC,
Full bridge strain gauge,
speed pulses

Input:
Inputs for tare, dosing start, stop or pause, etc.

Output (standard):
Counting pulses
kg or t (freely adjustable)

Optional:
4 – 20 mA / RS 232 / 485 /
Profibus DP / Profinet / Modbus TCP / etc.

Housing:
Stainless Steel

Type of protection:
IP67

Type of mounting:
Wall mounting or control cabinet installation

Working temperatures:
-10°C to +40°C

Frequently asked questions

What levels of accuracy can be obtained with weigh feeders?

With optimum design of the system, measurement errors of less than 0.5 or 1% can be achieved.

What measuring ranges can be covered?

Where throughput quantities are below 300 kg/h the measurement error increases significantly. There are virtually no functional limits at the top end of the scale.

 

For what applications are weigh feeders used?

There is a very wide spectrum of uses. The weighers are frequently used for constant feeding of mills and driers and for ratio and process control. Weigh feeders are very suitable for (pre) loading of silo vehicles and for batch dosing.

What are the requirements for maintenance?

The weighing components (load cell, electronics and rotary encoder) are largely maintenance-free. Depending on the product, however, periodic inspection of the belt and the metering wheel is sensible. In the case of closed systems, the scraped-off and return flow material should be regularly removed.

What are the main components of the weigh feeder?

A weigh feeder consists of a belt conveyor with a driving drum, a tail drum, the conveyor belt and the supporting stations for the top and bottom belt. The weighing components are one or more precision load cell(s), the rotary encoder for the conveying speed and the display and evaluation unit. In many cases, what is known as a „gravimetric tensioning device“ is used.

In which industries are weigh feeders used?

Weigh feeders are used predominantly in the construction materials industry, the animal feed and food industry and in the recycling sector.

Is calibration of the system necessary?

As a matter of principle, we recommend that every bulk weigher is calibrated for the conveyed product. In every case, it is necessary to calibrate the zero point, once installation is complete. To optimise the weighing accuracy, a known reference quantity should be fed across the weigher. Mathematical calibration and calibration with static weights lead to greater deviations.

We are delighted to offer personal assistance with your planning
Uncomplicated, individual and practice-oriented