A pneumatic conveying RFQ needs enough material and process data for suppliers to assess the duty and identify the assumptions behind it. Powder identity alone is not enough: density, moisture, size distribution, flow behaviour and test provenance affect the assumptions behind the duty.
A strong roots blower RFQ begins with a controlled material data package. The package does not need every possible laboratory test, but it must identify the properties that can change feeding, transport, separation and pressure demand.
Establish Material Identity
The record should identify supplier, grade, production route, batch or sampling date and expected variability. Recycled content, coatings, additives and upstream drying or milling can change behaviour even when the commercial product name remains unchanged.
The sample should represent the condition entering the conveying system. If fines accumulate during transport or storage, a separate worst-case sample may be required. Photos and a retained reference sample can help resolve later disputes about whether the delivered material matches the design basis.
Define Size, Shape and Density
Particle-size data should include a distribution and measurement method. Shape descriptions should identify angular, flaky, fibrous, spherical or agglomerated material where relevant. These features influence aerodynamic response, packing, wear and filter loading.
Density data need clear labels. Particle density supports interpretation of drag and inertia. Loose or aerated bulk density describes expanded states; tapped or consolidated density describes tighter packing. The project should record a credible range and the procedure used to create each condition.
Record Moisture and Environmental State
Moisture can create liquid bridges, increase wall adhesion or reduce electrostatic charging. Hygroscopic powders may absorb water during storage or from inadequately conditioned conveying air. Temperature can soften polymers, change coatings or move the process toward condensation.
The data package should therefore state moisture range, product temperature, ambient limits and storage duration. If these conditions can vary seasonally, the conveying design should be checked at the credible extremes rather than only at the convenient laboratory condition.
Match Flow and Aeration Tests to the Equipment
Simple indices can compare batches, but hopper design may require stress-dependent shear and wall-friction data. Aeration and permeability tests can show how the material responds to gas flow, retains pore pressure or deaerates after reaching the receiver.
Each test should have a declared purpose. A result used to size a hopper outlet should not be transferred automatically into a pipeline transport model. Likewise, a fluidization observation does not establish a stable pneumatic conveying regime.
Identify Product-Quality and Safety Constraints
The RFQ should state acceptable attrition, fines, temperature rise and contamination limits. Abrasive products may require a wear strategy; fragile granules may require lower velocity and controlled bends. Combustible or toxic powders need separate safety and containment requirements based on representative test evidence.
These constraints can be more decisive than nominal throughput. A system that moves the required mass but damages the product or overloads the filter has not met the commercial objective.
The data package should also state known exclusions. If no representative trial covers wet product, recycled fines or a future grade, those conditions should remain outside the performance commitment until reviewed. An explicit exclusion is more useful than a hidden assumption because it gives sales, engineering and operations the same change-control boundary.
Translate the Data into a Verified Duty
Material properties define the feasible transport window together with feeder and route data. The final enquiry should state blower-inlet volume at declared conditions, total differential pressure, control range and normal plus maximum credible operating cases.
A complete powder data package connects each measured property to a design decision and makes missing evidence visible before quotation. Conveying assumptions can then be confirmed through representative testing or plant history instead of being filled with supplier-specific estimates.
Glossary
Batch identity: Traceable link between a tested sample and the produced or supplied material lot.
Credible range: Supported minimum-to-maximum property interval expected during normal and foreseeable operation.
Material data package: Controlled collection of sample identity, test methods, results, conditions and acceptance requirements.
Material state: Physical condition defined by moisture, temperature, aeration, consolidation and handling history.
Property uncertainty: Quantified or qualified doubt associated with sampling, testing and natural material variation.
Retained sample: Preserved representative material used for later comparison or dispute resolution.
Test purpose: Specific engineering decision for which a material measurement is considered valid.