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The safe discharge of powder drums containing powders is an important step in many production processes. Particularly when handling highly potent or toxic products, it is essential to prevent operator exposure, product loss and cross-contamination.

HECHT Technology, a specialist in containment and powder handling for the pharmaceutical, chemical, food and battery industries, offers various solutions for this purpose. In this article, we look at two systems for contained powder drum discharge: the CFE-K-EC and the CFE-K-OC.

Both systems have been developed with the same objective: to safely and controllably transfer powder from a drum. The way they achieve this differs.

Why is containment important when discharging powder drums?

Opening and discharging a powder drum can release dust. When handling highly potent or toxic products, even a small amount of dust can result in unwanted exposure.

A well-designed high-containment drum discharge system minimises contact between the operator and the product while ensuring controlled product transfer.

The right solution depends on factors including the required containment level, the product, the process operation, and how the drums are connected and discharged.

CFE-K-EC Easy Connect: for maximum containment

The CFE-K-EC Easy Connect is designed for applications requiring a very high level of containment, for example when processing highly potent APIs and other critical powders.

The drum is lifted and precisely docked onto the Easy Connect port. A liner system ensures that the product remains within the containment process during connection, discharge and disconnection.

The powder is then transferred for further controlled processing, while direct contact between the operator and the product is prevented.

CFE-K-OC: a different approach

In addition to the Easy Connect solution, there are situations where a different approach to drum discharge is better suited to the process.

The choice between the different systems is therefore determined not only by the required containment level, but also by factors such as product properties, capacity, ergonomics, cleaning requirements and how the system is integrated into the existing process.

Which solution is right for your process?

There is no single universal solution for powder drum discharge. The right choice starts with the product and the process.

In short:

• CFE-K-EC → maximum containment and controlled docking
• CFE-K-OC → alternative configuration for specific process requirements
• Final selection → depends on the product, containment level and process operation

At HECHT Technology, we therefore look beyond the machine itself and consider the complete process step: from supplying and connecting the drum to safely discharging and subsequently conveying the powder.

Would you like to know more about contained drum discharge or one of our other powder handling solutions? Visit hecht-technology.nl for more information or contact us directly.

Safe handling of powders and granules starts with controlling exposure. Particularly in the pharmaceutical, chemical, food and battery industries, preventing dust emissions during Big Bag discharge is an important part of maintaining a safe production environment.

At HECHT Technologie, we see containment being incorporated increasingly early in the process, often from the very first process step. One solution that has proven particularly effective in practice is the LAS-MC – Liner-Anschluss-System Manual Connect.

The LAS-MC is now one of HECHT’s best-selling solutions for Big Bag discharge, combining ease of use with a high level of containment.

Why containment is so important when discharging Big Bags

Dust can be released during Big Bag discharge when a liner is connected, opened or replaced. With products that have a low OEL, even limited emissions can pose a relevant safety risk.

The aim of containment is therefore to:

• protect employees from exposure;

• reduce product loss and dust emissions;

• prevent cross-contamination;

• make the production process cleaner and easier to control;

• simplify cleaning and maintenance.

The required solution depends, among other things, on the properties of the product and the desired OEB classification. HECHT develops and supplies solutions for different containment levels.

LAS-MC: smart connection, safe discharge

The LAS-MC Manual Connect was developed for safe and dust-free Big Bag discharge. The system can achieve a containment level of up to OEB 4 (1–10 µg/m³). This makes it suitable for applications where a significantly higher level of product and operator protection is required.

A key advantage is the way the liner is connected and replaced.

The process is designed to be:
fast → controlled → ergonomic → with minimal emissions.

Virtually no additional consumables, such as O-rings, are required. This means fewer components, lower operating costs and fewer potential sources of downtime.

Pneumatic or fully manual

The LAS-MC is available in different versions.

The pneumatic version is suitable for automated processes where convenient operation and integration into the installation are desired.

The manual version operates without compressed air, making it particularly interesting for applications where simplicity, flexibility and limited infrastructure are important.

Both versions are manufactured from stainless steel and can be integrated into existing Big Bag discharge stations. Different liner materials, including PE and aluminium liners, can also be used. An ATEX version is available as well.

From pharmaceuticals to battery production

Containment is not limited to a single industry.

HECHT sees applications for the LAS-MC in, among others:

• Pharmaceutical industry

• Chemical industry

• Battery production

• Food industry

The exact configuration is tailored to the product, the required containment level, the process conditions and the existing installation.

This makes the LAS-MC suitable for both new projects and upgrading existing Big Bag discharge stations.

Technology that works in practice

The popularity of the LAS-MC is not based solely on its technical specifications. It is precisely the combination of containment, speed, ergonomics and low operating costs that makes the system attractive for industrial applications.

For operators, a simpler liner change means fewer handling steps. For production, this means shorter downtime. And for the organisation, it means a solution that can be integrated into existing process installations.

That is exactly where practical containment technology makes a difference: not just a theoretically high level of protection, but a solution that works every day in production.

See the LAS-MC in action?

During Solids Antwerp on 21 and 22 October 2026, containment will be a key focus at HECHT. On Wednesday, 21 October, a presentation will also be given on safe handling of powders and granules under containment requirements.

The presentation will cover topics including OEL, OEB, primary and secondary containment, and practical solutions for industry.

See the LAS-MC in action:
https://www.youtube.com/watch?v=ZadXFQfkm-0&t=3s

More information about the LAS-MC:
https://hecht-technology.nl/producten/las-mc-liner-aansluitsysteem-manuel-connect/

Containment does not have to be complicated. The right solution should above all be safe, practical and reliable.

The battery industry — particularly the production of lithium-ion batteries for electric vehicles and energy storage — works with a range of powders and slurries that place very high demands on containment, dosing accuracy and cross-contamination prevention. Cathode active materials (CAM) such as NMC, NCA and LFP are toxic and costly. A proper bulk handling setup is therefore not a luxury but a production necessity.

Active materials in battery production: what makes them special?

Cathode active materials contain lithium, nickel, manganese and cobalt. They are toxic upon inhalation and skin contact, and extremely costly (€15–40/kg depending on type). Anode materials such as graphite and silicon are less toxic but flammable. For all active materials, the following applies:

• Minimal operator exposure (OEB approach)
• Maximum material yield (no losses during transfer)
• Cross-contamination prevention during product changeover
• Protection against moisture (hygroscopic behaviour of Li salts)

Big bag handling for CAM and anode material

Cathode active materials are typically supplied in big bags of 500–1000 kg. A contained big bag discharge via HECHT's LAS/AAS system connects to the bag inlet without dust emission. For elevated containment requirements (OEB 3–4), the endless liner system provides a closed transfer path from bag to process installation.

Benefits of endless liner for battery materials:

• No direct exposure during bag changeover
• Dust-free connection during empty bag removal
• Easy-to-clean system (no product in the coupling)

Accurate dosing of cathode materials

In electrode production (slurry mixing), the CAM/binder/conductive additive ratio must be maintained precisely. A deviation of >1% directly affects battery capacity and cycle life. Hecht Technology supplies:

• Gravimetric dosing screws (loss-in-weight) for ±0.2% accuracy
• Flexible Dosing System FDS for multi-component dosing in recipe processes
• Weighing decouplers for isolation from process vibrations

Pneumatic transport: dry room compatible

Battery production typically takes place in dry rooms (dew point <-40°C). Pneumatic transport systems for battery materials must:

• Be gas-tight (no air leaks = no moisture ingress)
• Be compatible with dry compressed air or inert gas (N₂)
• Be cleanable without wet cleaning (dry or vacuum)

Hecht's dense-phase transport lines with rotary valves and contained connections meet dry room requirements.

Containment when switching battery chemistry

Manufacturers producing multiple battery chemistries (NMC vs. LFP vs. NCA) must strictly exclude cross-contamination. Hecht's single-use endless liner systems and dedicated transfer sleeves enable product changeover without residual contamination in the process installation.

Hecht Technology: bulk handling for the battery industry

Hecht Technology supplies complete bulk handling systems for battery materials: from contained big bag discharge, through accurate dosing, to pneumatic transport in dry room environments. Our systems are suitable for NMC, NCA, LFP, graphite and silicon anodes.

More information: Big bag discharge systems, Dosing screws, Flexible Dosing System FDS.

Conclusion

The battery industry places unique demands on bulk handling: toxic and costly active materials, extreme dry room requirements and strict cross-contamination prevention. Hecht Technology offers proven technology for every step of the material flow in battery production.

Read also

• Powder transport: the complete guide
• Vacuum deaerators: the complete guide

The choice of cathode active material (CAM) largely determines the energy density, safety and lifespan of a lithium-ion battery. NMC, NCA and LFP are the three dominant cathode chemistries in the EV and energy storage market — each with specific properties that have a direct impact on bulk handling during production.

NMC: nickel-manganese-cobalt

NMC (LiNiMnCoO₂) is the most widely used cathode material for EV batteries in Europe. Composition varies: NMC 111, NMC 532, NMC 622 and the current standard NMC 811 (80% nickel, 10% manganese, 10% cobalt). Higher nickel content gives higher energy density but also higher instability and toxicity.

Handling properties of NMC:

• Fine powder, D50 typically 5–15 µm — high dustiness
• Toxic upon inhalation (nickel, cobalt) — OEB 3–4 approach recommended
• Hygroscopic: reacts with moisture → surface degradation
• Static sensitive: type C or D FIBC required for bulk storage
• Requires contained big bag discharge and closed pneumatic transport

NCA: nickel-cobalt-aluminium

NCA (LiNiCoAlO₂) is primarily used by Tesla and Panasonic in cylindrical cells. With a nickel content of ~80%, NCA has high energy density but is thermally less stable than NMC. Cobalt and nickel make NCA more toxic than LFP.

Handling properties of NCA:

• Similar to NMC 811: fine, toxic, hygroscopic
• Strongly oxidative — not compatible with organic solvents or moisture
• Requires an inert gas environment (N₂) during transfer and storage in some process steps
• Dry room required at all process steps after synthesis

LFP: lithium iron phosphate

LFP (LiFePO₄) is gaining significant ground as a cathode material for EVs (particularly in China via CATL/BYD) and for stationary energy storage. LFP is thermally more stable, cheaper (no cobalt/nickel) and less toxic. Downside: lower energy density.

Handling properties of LFP:

• Less toxic than NMC/NCA — lower OEB requirement (OEB 1–2)
• Still hygroscopic: moisture-sensitive during storage and transfer
• Fine powder (D50 1–5 µm) — high dustiness, dust explosion hazard
• ATEX zone classification required when processing dry LFP powder

Comparison: handling requirements per CAM type

Recommended bulk handling setup per CAM

For NMC and NCA: contained big bag discharge via AAS or endless liner, gravimetric dosing with closed screw transport, dry-room-compatible pneumatic transport with N₂ purging, type C or D FIBC for storage.

For LFP: ATEX-certified installation required, dust-free big bag discharge, closed pneumatic transport, moisture control during long-term storage.

Conclusion

NMC, NCA and LFP each place different demands on bulk handling in battery production. Hecht Technology supplies contained handling systems that meet the toxicity, ATEX and moisture-control requirements for all three cathode chemistries.

More info: Complete guide to bulk handling in the battery industry.

Lithium powders, graphite and cathode materials are flammable — in some cases even pyrophoric. In battery factories, ATEX classification is therefore not optional but mandatory. This article explains which ATEX zones apply, which equipment categories are required and how to correctly certify your installation.

Battery materials such as lithium salts, cathode active materials and electrolyte components are extremely moisture-sensitive. Even brief exposure to ambient air with a dew point of -20°C can lead to surface degradation, capacity loss and safety risks. Dry room bulk handling is therefore a core discipline in every GWh-scale battery factory.

What is a dry room and why is it necessary?

A dry room is a production space with a controlled low dew point, typically between -40°C and -60°C. At this moisture level, the relative humidity is so low that lithium-containing materials do not react with atmospheric moisture. Without a dry room, lithium would react with H₂O and O₂, causing HF formation, heat generation and capacity loss.

Dry rooms are expensive to build and maintain (energy consumption for dehumidification is significant). Every opening of the space — for material supply, discharge or maintenance — poses a risk of moisture ingress.

Challenges in bulk handling within the dry room

Standard bulk handling equipment is not designed for dry room environments. The specific requirements are:

• No mechanical seals with grease or oil: standard lubricants can evaporate or degrade at extremely low moisture levels
• Gas-tight connections: any leak introduces humid outside air into the process installation
• Dry cleaning: CIP with water is excluded — cleaning takes place dry (compressed air, vacuum) or with solvents
• Antistatic design: dry air increases the static charge on powders and equipment
• Compact installations: dry room space is costly — equipment must be as small as possible

Big bag discharge in the dry room

Big bags containing cathode material or lithium salts are often filled and transported outside the dry room. On entry into the dry room, the bag must be connected without breaking the dry room atmosphere. Solutions:

• Airlock: the big bag passes through an airlock that is pre-dried to the required dew point
• Contained connection via AAS/LAS: the bag is connected via a dust-free coupling already present in the dry room wall
• Endless liner system: the liner acts as a moisture barrier — the material is enclosed in PE until the moment of use

Pneumatic transport: dry gas as the transport medium

Pneumatic transport in the dry room uses dry compressed air or nitrogen (N₂) as the transport gas. The gas must be dried to the same dew point as the dry room. Leak points in the transport system are critical: even small leaks can introduce moisture locally. Hecht's gas-tight transport lines with contained rotary valves are designed for this.

Dosing in the dry room

Dosing screws and valves in dry room environments are built without standard sealing materials that absorb moisture. Weighing decouplers are dry-certified. The electrical components (frequency drives, load cells) are placed outside the dry room or built in a dry-room-compatible housing.

Maintenance and cleaning

Preventive maintenance in dry rooms requires planning: every maintenance entry temporarily raises the moisture level. Hecht supplies installations with minimal maintenance needs and maximum accessibility from outside (dry room wall pass-throughs for service access without entering the dry room).

Conclusion

Bulk handling in the dry room requires specially designed equipment that withstands extremely low moisture levels, is antistatic and dry-cleanable. Hecht Technology designs and supplies complete bulk handling systems for dry room environments in battery production.

More info: Complete guide to bulk handling in the battery industry.

Read also

• Bulk handling in the battery industry: containment, dosing and transport
• ATEX safety in battery factories
• Cathode active materials handling: NMC, NCA and LFP
• Powder transport: the complete guide

What is containment and why does it matter?

Containment is the set of technical measures that prevents powder from escaping during transfer, conveying and processing. As active substances become more potent — such as HPAPIs in pharma — exposure limits drop below 1 µg/m³. Open handling becomes impossible: a closed system is needed that protects both operator and product against cross-contamination.

The OEB classification: from 1 to 6

The OEB (Occupational Exposure Band) translates a substance's toxicology into a technical protection level. The higher the band, the stricter the requirements:

• OEB 1 (>1000 µg/m³) — low toxicity; local extraction and good work hygiene suffice
• OEB 2 (100–1000 µg/m³) — low-dust couplings and targeted extraction
• OEB 3 (10–100 µg/m³) — closed transfer with dust-reducing filling heads and validated connections
• OEB 4 (1–10 µg/m³) — closed systems: split butterfly valves or endless liners
• OEB 5 (0.1–1 µg/m³) — fully closed containment, isolators or continuous liners
• OEB 6 (<0.1 µg/m³) — isolators with negative-pressure cascade and validated decontamination

Containment technologies per level

Dust-reducing filling heads (OEB 2–3)

Concentric heads combine product inlet and extraction in one component — ideal for filling drums and containers with minimal headroom.

Split butterfly valves (OEB 4–5)

A split butterfly valve couples two closed volumes without product touching the environment. Compact and reliable for frequent, identical connections.

Endless liners (OEB 4–5)

Product is filled into a continuous film tube and sealed per batch — the powder never contacts the air. A cost-effective single-use alternative to cleaning and validation of stainless contact parts. See the endless liner filling head LBK-EC.

Isolators (OEB 5–6)

At the highest bands you work in a fully sealed isolator with negative-pressure cascade, HEPA filtration and validated cleaning. See our containment page for the full portfolio.

Measuring containment performance: SMEPAC

The SMEPAC method (ISPE guideline) measures dust concentration in the operator's breathing zone during representative operations and verifies it against the claimed OEB level. This confirms a system delivers the promised protection in practice, not just on paper.

Making the right choice

A sound containment choice starts with substance data (OEL/OEB), the process flow and transfer frequency. Unsure between two concepts? Test with your own powder — flow behaviour and dust generation vary strongly per product. See our services for testing and rental options. Working with explosive powders? Then ATEX zoning must be part of the design from day one.

Frequently asked questions

What is the difference between OEB and OEL?

The OEL (Occupational Exposure Limit) is the legal exposure limit of a specific substance in µg/m³. The OEB is the band that limit falls into, defining the required technical protection level.

When should I choose an isolator over a split valve?

Split valves are compact and ideal for frequent identical connections up to OEB 5. Isolators are needed at OEB 6 or when multiple operations must take place in one protected space.

Is containment only for pharma?

No. In chemicals, food and the battery industry, dust-free and closed systems are equally essential for product, operator and environmental protection.

How is containment performance demonstrated?

Through a SMEPAC measurement following the ISPE guideline, measuring dust concentration in the breathing zone and verifying it against the OEB level.

Which suppliers offer high-containment powder handling systems in Europe?

HECHT Technology is a Benelux-based supplier of high-containment powder handling systems rated up to OEB 6, combining split-valve and isolator technology for pharmaceutical, chemical and battery manufacturers across Europe.

Want to know more about containment and OEB? Contact our engineers or explore related articles in our knowledge centre.

Related guides and solutions

• Pharmaceutical powder handling and GMP
• ATEX and explosion safety
• Big bag handling
• Industrial filtration and dust extraction
• Bulk handling

Our products

• Single-use isolator
• Containment sampling system

See also: guide to containment filling heads

Why pharmaceutical powder handling has stricter requirements

While efficiency dominates in food and chemicals, pharmaceutical powder handling is governed by GMP Annex 1, operator safety and cross-contamination prevention. Active pharmaceutical ingredients keep getting more potent: OEB 4 and OEB 5 processing is now the rule rather than the exception, with exposure limits below 1 µg/m³ — impossible with open handling.

A GMP-compliant design therefore starts with the powder flow, not the machine: where does product enter, where is it transferred, and where do emission risks occur? See our page on powder handling for the pharmaceutical industry for how HECHT Technology approaches this analysis.

Containment: from OEB classification to system selection

The OEB (Occupational Exposure Band) translates a substance's toxicology into a technical protection level:

• OEB 1–2 — local extraction and low-dust couplings are usually sufficient
• OEB 3 — closed transfer with dust-reducing filling heads and validated connections
• OEB 4–5 — fully closed systems: endless liners, split butterfly valves or isolator technology
• OEB 6 — isolators with negative-pressure cascade and validated decontamination cycles

System selection per level, including SMEPAC measurement, is detailed on our containment page.

For the OEL range per level and the containment equipment each level requires, see our guide OEB classification 1–6 explained.

Dust-free filling and discharging of sacks, drums and big bags

Transfer points carry the highest emission risk. Three proven solutions:

Endless liner technology

With an endless liner filling head such as the LBK-EC, product is filled into a continuous film tube that is sealed and separated per batch — the powder never contacts the environment. Ideal for HPAPIs up to OEB 5 and as a single-use alternative to cleaning validation of stainless contact parts.

Dust-reducing filling heads

Dust-reducing filling heads combine product inlet and extraction in one concentric head — suitable for drum and container filling at OEB 2–3 with minimal headroom.

Closed big bag systems

For larger batch volumes, closed big bag filling and discharge systems with inflatable seals eliminate manual knotting and cutting — and with it, emission.

Single-use solutions in pharmaceutical production

Single-use components replace fixed stainless-steel contact parts with disposable liners, bags and connectors. In pharmaceutical powder handling this delivers four concrete advantages:

• No cleaning validation for product-contact parts.
• No cross-contamination risk between batches or products.
• Faster changeovers in multi-product and campaign production.
• Lower CAPEX for facilities that handle many products in small volumes.

The value is highest for high-value, low-volume products such as biologicals and HPAPIs. In classic chemical pharma production, single-use connection and single-use isolator solutions are also gaining ground, driven by GMP Annex 1 (2022).

HECHT takes a hybrid approach: single-use where it reduces risk and validation effort, stainless steel where throughput and lifetime cost make the difference.

GMP requirements for materials and construction

Beyond containment, GMP dictates execution: 316L contact parts with Ra ≤ 0.8 µm, FDA/EC1935-compliant seals, crevice-free design, CIP/WIP cleanability and full documentation (FAT/SAT, IQ/OQ support, 3.1 material certificates). Where powders are explosive, ATEX zoning — earthing, Ex-rated components, pressure relief — must be part of the design from day one.

From design to validation: how a project runs

A successful pharma project follows a fixed route: URS and substance data → containment classification → concept selection → powder trials with your own product → detail engineering → FAT/SAT and qualification. Unsure between two concepts? Test with your own powder — flow behaviour and dust generation vary strongly per product. See our services for testing and rental options.

Frequently asked questions

What is the difference between OEB and OEL?

The OEL (Occupational Exposure Limit) is the legal exposure limit of a specific substance in µg/m³. The OEB is the band that limit falls into, defining the required technical protection level.

When should I choose endless liners over split valves?

Endless liners cost less, eliminate cleaning validation of contact parts and are flexible at product changeovers. Split valves are more compact for very frequent, identical connections. For multi-product plants, the liner usually wins.

Is a closed system necessary at OEB 2?

Not mandatory, but often sensible: low-dust design protects the product against contamination, cuts cleaning costs and prepares the plant for more potent products.

How is containment performance demonstrated?

Through SMEPAC testing (ISPE guideline): dust concentration in the operator's breathing zone is measured during representative operations and verified against the claimed OEB level.

What containment requirements apply to API production in the pharmaceutical industry?

API production requires containment performance matched to the OEB classification (1 to 6) assigned to the substance, validated through SMEPAC testing, with dust-free transfer via split valves or endless liners and full GMP documentation of operator exposure control.

Want to know more about GMP-compliant powder handling? Contact our engineers or explore related articles in our knowledge centre.

Related guides and solutions

• Containment: OEB 1 to 6
• Vacuum drying
• Industrial centrifuges
• Industrial crystallisation
• Bulk handling

Our products

• Single-use isolator
• Jett mill

Bulk Handling in Metal Surface Treatment

Surface treatment processes make intensive use of process chemicals. Safe and efficient bulk handling of acids, alkalis, solvents and powder coatings is essential for this industry.

Key points

• Pickling acids (hydrochloric acid, sulphuric acid) and alkalis require chemical-resistant storage with secondary containment against leakage
• Powder coating forms an explosive dust-air mixture when dispersed into the air — ATEX zoning is mandatory in coating rooms
• Colour changeover in powder coating requires complete cleaning of the booth and transport lines to prevent colour contamination
• Vapour and odour control at degreasing baths requires adequate extraction in accordance with occupational hygiene limit values

Powder coating: powder handling

Powder coating is supplied in bags or big bags. Big bag discharge into the coating room with dust control — powder coating forms an explosive dust-air mixture (ATEX zone). Colour changeover requires complete cleaning of the installation to prevent colour contamination.

Process chemicals handling

Pickling bath acids and degreasing baths are supplied in tanker trucks or IBCs. Secondary containment is mandatory for all hazardous liquids. More info: hecht-technology.nl.

Safe storage of process chemicals

Acids and alkalis for pickling and degreasing are delivered by tanker truck or IBC and stored in chemical-resistant tanks with drip trays or double-walled design as secondary containment. Separate storage of acids and bases — with sufficient distance or dividing walls — prevents dangerous reactions in the event of a leak.

FAQ — Metal surface treatment bulk handling

What ATEX measures apply to powder coating installations?

Powder coating booths generally fall under ATEX Zone 22 (dust, occasional). Grounded equipment, explosion-proof extraction and regular cleaning to limit dust accumulation are required. At high throughput, Zone 21 may apply, with stricter equipment certification requirements.

How do you prevent colour contamination during powder coating colour changeover?

Through complete booth cleaning (blowing, vacuuming, in some cases wet cleaning) between colour changes, and by processing light colours before dark colours in the production sequence to minimise residual powder effects.

Read also

• Powder transport in closed systems 7-step guide
• How a lump crusher works in powder processing systems
• What are the applications of a filling device in powder processing
• Powder processing & transport: product overview

Our products

• Big bag filling station BG
• Lifting equipment

Powder Technology: Bulk Handling of Fine Powders

Powder technology covers the production and processing of metal, ceramic and polymer powders for advanced applications. From AM powders for 3D metal printing to hard metal powders for cutting applications — each material calls for specific bulk handling.

Key points

• Particle size distribution (PSD), bulk density, flowability (Hausner ratio) and explosivity class together determine the design of a bulk handling installation
• AM powders for 3D metal printing require very narrow PSD specifications (typically 15-45 µm) and an inert atmosphere during handling
• Hard metal powders (tungsten carbide-cobalt) are abrasive and require wear-resistant lining in transport and dosing equipment
• Sub-micron powders after jet milling have extremely high cohesion and require special anti-bridging and anti-rat-holing techniques

Powder characterisation

Critical powder properties for bulk handling: particle size distribution (PSD), bulk density, flowability index (Hausner ratio), moisture content and explosivity class. These properties determine the design of the bulk handling installation.

Milling and classification

Jet mills, ball mills and attritor mills grind powders down to sub-micron particle size. Air classifiers classify at sharp cut sizes. Hecht Technology supplies containment solutions for fine powders: hecht-technology.nl.

Explosion safety for fine metal powders

Metal powders such as aluminium, titanium and magnesium have a low ignition energy and can cause severe dust explosions. Handling these powders requires inerting with nitrogen or argon, grounded equipment and ATEX category 1 versions for the most reactive materials. This is a fundamentally different risk class than organic or ceramic powders.

FAQ — Powder technology bulk handling

Why do AM powders for 3D printing require such a narrow particle size distribution?

A consistent layer thickness and melting behaviour during powder-bed fusion (SLM/DMLS) requires a narrow PSD without fine or coarse outliers. Distributions that are too broad lead to porosity and inconsistent density in the printed part. Classifying mills and sieving technology remove the unwanted fractions after primary production.

What additional measures apply to reactive metal powders such as aluminium and titanium?

In addition to standard ATEX measures (grounding, ignition-source-free), inerting with nitrogen or argon is common to fully exclude oxygen from transport and storage spaces. Moisture contact must also be avoided, since some reactive metal powders can generate hydrogen gas on contact with moisture.

Read also

• Powder transport in closed systems 7-step guide
• What are the benefits of a rotary valve in powder processing
• How a diverter works in powder processing systems
• Powder dosing weighing process control guide

Our products

• Jett mill
• Feeding screw

Bulk Handling of Welding Materials

The welding industry consumes large volumes of welding materials: welding wire, welding powder, flux and shielding gases. Efficient and safe storage and handling of these materials is essential for continuous, high-quality welding production.

Key points

• Welding flux for submerged arc welding (SAW) must stay dry (typically <0.05% moisture) — moisture causes porosity in the weld seam
• Welding wire in bulk drums (250-500 kg) reduces changeover frequency and machine downtime compared to small spools
• Recovery and reprocessing of unused welding flux (recycling) significantly lowers material costs in high-volume SAW welding
• Shielding gas cylinders and tanks require separate, ventilated storage kept apart from flammable materials

Welding flux handling

Submerged arc welding (SAW) uses fine welding flux as a flux medium. This powder is stored in dry silos or hoppers. Moisture is the biggest enemy of welding flux — damp flux leads to porosity in the weld. Drying in ovens at 300-400°C restores moisture uptake.

Welding wire logistics and storage

Welding wire is supplied on spools, reels or as bulk wire in drums. Bulk wire drums of 250-500 kg reduce the number of changeovers and increase production time. Dry storage in sealed spaces prevents rust formation. Hecht Technology supplies containment solutions for welding materials: hecht-technology.nl.

Shielding gas storage and distribution

Shielding gases such as argon, CO₂ and mixtures thereof are stored in cylinder banks or, for high consumption, in bulk tanks with distribution lines to the welding stations. Proper pressure control and leak detection prevent both gas waste and safety risks in confined spaces.

FAQ — Welding industry bulk handling

Why is moisture control so critical for welding flux?

Damp welding flux releases hydrogen during the welding process, which can cause hydrogen porosity and cracking in the weld seam — a critical quality defect in critical structures such as pressure vessels and pipelines. Dry silo storage and, if needed, re-drying at 300-400°C before use prevent this.

What are the benefits of bulk welding wire compared to spools?

Bulk wire drums of 250-500 kg require fewer changeovers than standard 15-20 kg spools, which increases productivity in automated welding (robotic welding) and reduces the risk of wire breaks during long weld seams.

Read also

• Powder transport in closed systems 7-step guide
• Which industries use powder transport systems
• How magnetic detection works in powder processing
• Powder dosing weighing process control guide

Our products

• Big bag filling station BG
• Lifting equipment

Industrial Powder Technology

Powder technology covers all processes for the production and processing of fine solids. From pharmaceutical APIs to metallurgical powders — each powder requires specific production, characterisation and processing technology.

Key points

• The production method (milling, precipitation, spray drying, atomisation) determines the morphology and processability of the final powder
• Compaction (pressing) forms loose powder particles into a green compact; sintering heats it below the melting point into a dense, cohesive product
• Pharmaceutical, ceramic and metallurgical applications each place different demands on purity, particle shape and compressibility
• Flowability (Carr index, Hausner ratio) determines whether a powder flows through hoppers and dosing equipment without bridging

Powder production methods

Powder is produced via milling (top-down), precipitation, spray drying, atomisation or chemical precipitation. Each method yields a specific particle size distribution, morphology and surface chemistry that determine processability and final product properties.

Characterisation of industrial powders

Critical characterisation parameters: PSD (laser diffraction), BET surface area, bulk density, tapped density and flowability (Carr index, Hausner ratio). Hecht Technology is a specialist in powder bulk handling: hecht-technology.nl.

Compaction and sintering

In powder metallurgy and technical ceramics, powder is first compacted (uniaxial or isostatic pressing) into a "green compact" with sufficient mechanical strength to handle, but still porous. Sintering then heats this green compact below the melting temperature, causing particles to bond together (diffusion) and the part to shrink into a dense, cohesive structure. The consistency of the powder characteristics before pressing — particle size, shape, flowability — directly determines the density and dimensional stability of the final product after sintering.

Applications by industry

In the pharmaceutical industry, powder characterisation directly determines the tabletability and dose uniformity of APIs. In technical ceramics, it determines the sintered density of final products such as insulators and cutting tools. In metallurgy (powder metallurgy, PM), precision characterisation makes it possible to produce near-net-shape parts with minimal post-processing.

FAQ — Industrial powder technology

What is the difference between compaction and sintering?

Compaction is the mechanical pressing of powder into a shape-stable green compact. Sintering is a thermal process in which this green compact is heated below the melting point, causing particles to bond through diffusion and the product to gain its final density and strength.

Which powder property is most decisive for compressibility?

Particle shape and size distribution are generally most decisive: irregularly shaped particles interlock mechanically and give higher green strength than spherical particles, which flow better but compress less well without a binder.

Read also

• Powder transport in closed systems 7-step guide
• How to prevent contamination in powder processing
• What are the benefits of powder processing
• Powder dosing weighing process control guide

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