Weigh Belt Feeders

In a belt weighfeeder, material is conveyed on a flat belt, ensuring exceptionally gentle handling — without shearing or abrasion caused by a screw. This makes it the optimal solution for friable materials (flakes, pellets), large-particle products or highly abrasive bulk solids. A screw feeder, on the other hand, is better suited to fine, cohesive powders and offers a smaller footprint at lower feed rates. Additionally, a belt weighfeeder requires less headroom, which is a significant advantage in installations with limited overhead clearance.

The DTU is the optimal choice for low- to medium-bulk-density materials — in the food, chemical and cosmetics industries, where a hygienic stainless steel construction and an FDA-approved belt are required. The DTC, on the other hand, is designed for heavy, highly abrasive materials and harsh industrial environments — cement plants, lime works and building materials production, where feed rates of up to 1,000 t/h and a robust carbon steel construction are needed.

Yes — belt weighfeeders are perfectly suited for building proportional multi-component feeding systems. In such a configuration, multiple feeders dose different ingredients onto a common collecting conveyor, maintaining constant recipe ratios in a master/slave mode. These systems communicate via 4–20 mA analogue signals or industrial fieldbus protocols (Profibus, Modbus, EtherNet/IP). InterProcess designs and integrates these turnkey feeding lines.

Both belt weighfeeder models achieve an accuracy of better than 0.5% of setpoint, while the DTU can reach below 0.25% in select applications. Actual accuracy depends on a number of factors, including material properties, feed consistency, proper inlet hopper selection and system calibration.

Inlet hopper (metering hopper) selection depends primarily on the flow characteristics of the bulk material. For free-flowing materials, we use simple chute-type hoppers with an adjustable gate. For poorly flowing, bridging or aeration-prone materials, specialised hoppers are selected — equipped with a vibratory feeder, rotary airlock valve or screw pre-feeder. For dusty materials prone to fluidisation, settling chambers with deaeration chains are also used. Proper inlet hopper selection is critical for maintaining a stable material bed on the belt and, consequently, for achieving the required feeding accuracy.

Standard belt conveyors with belt scales are designed primarily for material transport — weighing is only an add-on function. A belt weighfeeder, in contrast, is purpose-built from the ground up for precise gravimetric feeding, which results in several key differences. First, its compact dimensions and short pulley centre distance minimise the influence of belt irregularities, temperature and vibration on measurement accuracy. Second, the gravity belt tensioner provides constant, repeatable belt tension regardless of operating conditions — eliminating the zero drift that in standard conveyors requires frequent recalibration. Third, a dedicated control system with PID belt speed regulation actively maintains the target mass flow rate, rather than merely measuring it. Importantly, the belt weighfeeder also features built-in belt cleaning mechanisms (internal and external scrapers) and a belt drift and slip detection system, which on standard conveyors are either optional or unavailable. All these features enable the belt weighfeeder to achieve accuracy below 0.5%, whereas a typical belt scale on a standard conveyor typically offers only 1–2%.