Bridging and Arching
Material forms a stable arch above the outlet and prevents the hopper or bin from discharging.
Material Flow Solutions
Bridging, Rat-holing, Buildup or Inconsistent Material Flow?
Rate Technology Systems helps manufacturers identify what is restricting material flow and evaluate the right combination of flow aids, discharge equipment, valves, feeders and flexible connections.
Identify the Process Problem
Material Flow Problems Are Usually Symptoms
A hopper that will not empty consistently does not automatically need a vibrator. The correct solution depends on the material, vessel geometry, operating conditions, discharge equipment and required process rate.
Rat-holing
Material flows through a narrow central channel while product remains stagnant along the vessel walls.
Wall Buildup
Cohesive or moist material adheres to internal surfaces, reducing usable capacity and restricting discharge.
Inconsistent Discharge
Surging, pulsing or variable material flow disrupts downstream feeding, conveying, batching or packaging.
Flooding or Flushing
Aerated or free-flowing powders discharge too quickly and overwhelm downstream equipment.
Operator Intervention
Operators are repeatedly hammering vessels, clearing blockages or adjusting equipment to maintain production.
Diagnose Before Selecting Equipment
Why Is the Material Not Flowing?
Reliable material flow begins with understanding the interaction between the bulk solid, the storage vessel and the downstream process.
Material Characteristics
Particle size, bulk density, moisture, cohesiveness, temperature, abrasiveness and compressibility all affect flow behaviour.
Hopper and Outlet Geometry
Wall angles, outlet dimensions, vessel shape and internal surfaces may promote or restrict reliable discharge.
Storage Conditions
Material may compact, absorb moisture, settle or change condition while stored for extended periods.
Downstream Equipment
A feeder, rotary valve, screw conveyor or closed gate can restrict discharge even when the vessel itself is properly designed.
Required Process Rate
The system must discharge material consistently at the rate needed by the downstream operation without uncontrolled flooding.
Material Flow Technologies
Solutions Based on the Process Requirement
The right solution may promote flow, control discharge, route material or improve the reliability of the surrounding process.
1. Promote Material Flow
Release Material That Is Bridging, Sticking or Packing
Flow-aid technologies introduce controlled energy or movement into the vessel to encourage cohesive or difficult materials to discharge more consistently.
- AirSweep Systems Directed pulses of compressed air help release fine powders from vessel walls and difficult discharge areas.
- Bin Activators Vibrating discharge devices promote flow across a larger area at the bottom of a bin or hopper.
- Industrial Vibrators Electric or pneumatic vibration can help address intermittent bridging, sticking and material buildup.
- Live Bottoms Multiple screws or moving-floor arrangements provide controlled reclaim from difficult bulk-storage vessels.
2. Control Material Flow
Regulate, Isolate or Meter the Discharge
Once material is moving, the process may still require accurate control. Gates, valves and feeders regulate how quickly material leaves the vessel and enters downstream equipment.
- Rotary Airlock Valves Provide controlled discharge while maintaining an air seal between process zones.
- Slide and Knife Gates Isolate bulk-solid flow for maintenance, process control or emergency shutoff.
- Volumetric Feeders Deliver material at a controlled rate based on feeder speed and calibrated material output.
- Gravimetric Feeders Continuously measure material weight to maintain more accurate feed rates and batch consistency.
- Screw Feeders Meter material from hoppers and bins into conveyors, mixers or downstream process equipment.
- Iris Valves Provide controlled, dust-contained discharge from drums, hoppers or bulk bags.
3. Transfer and Route Material
Move Material Away From the Vessel Reliably
In some applications, the apparent hopper problem is actually caused by downstream transfer equipment. The discharge device and conveyor must work together as one coordinated system.
- Diverter Valves Direct material between multiple process destinations, production lines or storage vessels.
- Flexible Screw Conveyors Provide enclosed, flexible transfer of powders and bulk solids between process stages.
- Screw Conveyors Move, elevate, distribute or collect material using engineered screw configurations.
- Bulk Bag Dischargers Promote controlled unloading from flexible intermediate bulk containers while reducing manual handling.
4. Maintain a Reliable Process
Support Flow With Better Containment and Process Visibility
Reliable material flow also depends on properly vented vessels, accurate level information and flexible connections that do not restrict equipment movement or create leakage points.
- BFM Flexible Fittings Provide flexible, tool-free connections between vibrating or moving equipment while improving dust containment.
- Flexible Sleeves and Connectors Connect process equipment while accommodating movement, vibration and alignment requirements.
- Level Sensors Monitor high, low or continuous material levels to reduce overfills, empty runs and process interruptions.
- Bin Vent Dust Collectors Manage displaced air during filling and help prevent vessel pressure or dust-release problems.
Information That Helps Us Review a Material Flow Application
The following details help determine which technologies should be considered:
- Material name and composition
- Particle size or particle-size range
- Loose and settled bulk density
- Moisture content and temperature
- Required discharge or feed rate
- Existing hopper, bin or silo dimensions
- Outlet size and hopper-wall angles
- Current downstream equipment
- Observed symptoms and frequency
- Indoor, outdoor or hazardous-area conditions
Why Rate Technology Group
We Start With the Process, Not a Predetermined Product
Rate Technology Group works across multiple equipment technologies, allowing us to evaluate the material-flow problem before identifying the most appropriate solution.
Understand the Material
Review the powder or bulk solid, its flow behaviour and the conditions affecting it.
Review the Process
Evaluate the storage vessel, discharge point, downstream equipment and production requirements.
Identify the Root Cause
Separate the visible symptom from the underlying flow, equipment or control limitation.
Recommend a Solution
Compare suitable technologies and coordinate with the appropriate equipment manufacturer.
Discuss Your Application
Still Fighting the Same Material Flow Problem?
Tell us what material you are handling, what the process is doing now and what you need it to do. We will help identify the likely causes and determine which material-flow technologies should be considered.
Application Review
Tell Us About Your Material Flow Problem
Tell us about your material, and application and we’ll help recommend the right approach.
No obligation. We will simply review your application and provide practical guidance within 24 hours.
