Abrasion-resistant · Abrasion-resistant
SILOFLAT/DISCHARGE
SILOFLAT/DISCHARGE is the specialised pressureless silo discharge hose in larger dimensions (ID 152-305 mm) with conductive inner lining (below 10⁶ ohm) and antistatic outer coating (below 10⁹ ohm). The hose is specifically designed for large silo discharge stations where dust explosion risk from cement, lime powder and bulk powder flow requires ATEX-related electrical discharge. Wear resistance confirmed with abrasion value 70 mm3 per ISO 4649 - better than standard SILOFLAT's 100 mm3. 3 bar working pressure and 9 bar burst pressure provide moderate-pressure discharge margin.
- -30 to +85 C
- Conductive core
- Antistatic cover
- Abrasion 70 mm³
- Silo discharge
- Dust explosion safety
Why this hose?
The dual electrical qualification (conductive core + antistatic cover) is the key to SILOFLAT/DISCHARGE's ATEX-suitable character. The conductive inner lining directly discharges static electricity from powder flow - this is the primary source of spark risk in powder handling. The antistatic outer coating ensures the hose's surroundings also get controlled discharge to ground. The combination is specifically designed for zone 22 (dust explosion zone) installations.
Wear resistance 70 mm3 abrasion value (vs. 100 mm3 on standard SILOFLAT) is a significant improvement in continuous operation. It means the hose can handle more abrasive powder media or higher flow rates than the standard version. The NR lining construction is specifically formulated for these heavy-duty powder applications.
Large dimensions (152-305 mm) are a specific product class for industrial-scale discharge stations. Smaller dimensions (76-102 mm from standard SILOFLAT) are only sufficient for local-scale discharge or smaller installations; for main supply pipes from large silos, the 152-305 mm dimension range is correct.
Where it is used
Large construction sites and infrastructure projects use the hose as standard cement discharge from mobile silos. A typical project has 20-50 m of SILOFLAT/DISCHARGE in 203 mm or 254 mm dimension from silo bottom to concrete mixing plant. The ATEX zone 22 properties ensure spark risk from cement dust is controlled.
Chemical production facilities use the hose for powder handling between silos and process stations. The dual conductive/antistatic qualification is typically required by GMP or pharma-related regulations specifying ATEX suitability for powder transport equipment.
Industrial silo discharge stations (feed, chemical, construction-site cement) use the hose as a heavy-duty discharge solution. The layflat construction allows multiple hoses to be stored on the same silo truck or distribution station, reducing logistics costs over time.
The hose is colloquially known as a silo discharge hose, cement Auslauf hose or large discharge hose.
Technical specifications
The hose's key specifications are briefly summarised below. The combined conductive core + antistatic cover is specifically designed for ATEX zone 22-related silo discharge stations.
| Inner material | NR (natural rubber) |
|---|---|
| Outer material | SBR/NR |
| Reinforcement | Textile plies |
| Colour | Black (both inner and outer) |
| Construction | Layflat (collapses flat) |
| Temperature range | -30 to +85 C |
| Working pressure | 3 bar |
| Burst pressure | 9 bar |
| Electrical resistance core | <106 Ω (conductive) |
| Electrical resistance cover | <109 Ω (antistatic) |
| Abrasion value | 70 mm³ per ISO 4649 |
| Manufacturer SKU | 3546 |
Dimensions and ordering
The table shows the hose's 4 standard dimensions. All have the same pressure rating (3 bar / 9 bar burst). Smaller dimensions are delivered on 20 m rolls, and the 305 mm version on 10 m rolls.
| Inner Ø |
Outer Ø |
Wall thickness |
Working pressure |
Burst pressure |
Max. length |
Weight |
Roll |
Article no. |
|---|---|---|---|---|---|---|---|---|
| 152 | 166 | 7 | 3 | 9 | 20 | 4.19 | 20 | 3546152166 |
| 203 | 217 | 7 | 3 | 9 | 20 | 5.64 | 20 | 3546203217 |
| 254 | 270 | 8 | 3 | 9 | 20 | 7.62 | 20 | 3546254270 |
| 305 | 323 | 9 | 3 | 9 | 10 | 10.4 | 10 | 3546305323 |
Fields without a value (—) are not specified in the manufacturer's factsheet. Overpressure and underpressure values are recommended operating limits; the product can be subjected to higher loads on request. Bend radius is measured along the inside of the hose bend.
Standards and compliance
The hose is qualified per the central standards for wear-resistant discharge hoses with electrical properties.
- ISO 4649 (formerly DIN 53516). International standard for determination of wear resistance in rubber. The hose's 70 mm3 abrasion value is tested per this standard.
- ISO 8031. Determination of electrical and surface resistance in rubber hoses. The hose's core (<10⁶ Ω) and cover (<10⁹ Ω) are tested per this standard.
- EN ISO 1307:2008. European standard for rubber and thermoplastic hoses for general use.
- EN 12115. European standard for rubber and thermoplastic hoses.
- RoHS Directive (2011/65/EU). Restriction of hazardous substances.
- REACH (EC 1907/2006). Registration of chemical substances.
- ATEX 2014/34/EU. EU directive for equipment in potentially explosive atmospheres. The hose has relevant electrical properties, but explicit ATEX declaration is not in the factsheet.
Documentation and downloads
Additional documents about this hose, its compliance and installation. Click to download as PDF in a new tab.
Help with material selection
If you're choosing a hose and are unsure about the right resistance level or zone classification, these two articles are a good place to start:
The invisible weakest link
Why a conductive or antistatic hose isn't sufficient on its own — and what grounding means for the complete system.
Know your ohm
The difference between antistatic and conductive, which resistance limits apply where, and how to measure them correctly.
Industries that use it
SILOFLAT/DISCHARGE is used in large silo discharge stations where powder explosion risk requires a conductive wall - typically at large construction sites, in chemical production facilities and industrial silo installations.
Construction sites and infrastructure projects use the hose for large cement discharge stations from mobile silos or cement trucks. The ID 152-305 mm range covers the typical dimensions for industrial cement distribution. The combined wear resistance (70 mm3) and electrical discharge make the hose suitable for continuous operation over many months.
Chemical industry uses the hose for bulk powder discharge from storage silos to process and transport tanks. Powder flow (lactose, mannitol, chemical raw materials) generates static electricity, and a conductive hose discharges this charge to the ground connection. This is a mandatory ATEX zone 22 property in many powder handling facilities.
Large farms and industrial feed facilities use the hose for feed distribution from central silos to transport vehicles. The large dimensions (203-305 mm) allow high flow rates, and the layflat construction allows the hose to be stored compactly between uses.
Custom lengths and assemblies
The hose can be delivered cut to desired lengths. The standard roll can be supplemented with shorter pieces or multiple rolls by arrangement.
At Particulair we advise on couplings and sizing. Send us a sketch of your application and we will assess the right variant and length.
Frequently asked questions
What is the difference between SILOFLAT/DISCHARGE and standard SILOFLAT?
The DISCHARGE variant is the pressureless version in larger dimensions (152-305 mm) with explicit antistatic outer coating + conductive inner lining. Standard SILOFLAT has pressure rating (4 bar) and is in smaller dimensions (76-102 mm) without ATEX-relevant electrical properties. DISCHARGE is specifically for large silo discharge stations where dust explosions are a risk.
What does pressureless mean?
Pressureless means the hose is designed for low-pressure discharge flow (typically below 1 bar), where the material flows under gravity or light pneumatic drive. The hose is NOT rated for high-pressure pump applications - for those we recommend BETONCORD/10 or TURBOCORD which have specific pressure ratings.
What is the difference between antistatic and conductive here?
The hose's inner tube is qualified as electrically conductive (below 10⁶ ohm) - providing direct discharge of static electricity from powder flow. The outer coating is antistatic (below 10⁹ ohm) - providing moderate discharge to surroundings. The combination is specific to ATEX zone 22 applications where powder flow generates static electricity and the hose surroundings are ATEX zone 22.
How many dimensions are in the range?
4 dimensions: ID 152, 203, 254 and 305 mm. These are larger dimensions than standard SILOFLAT - typical for industrial silo discharge stations. Smaller dimensions are delivered on 20 m rolls; the 305 mm variant on 10 m rolls. Pressure is 3 bar with 9 bar burst pressure - moderate-pressure discharge.
What is Auslauf in German?
Auslauf (German) = Discharge / Outlet (English) = Outflow (Danish). It refers to the process where powder or bulk medium 'flows out' from silo to transport container or process installation. The hose is specifically designed for this 'outflow application', not pump pressure applications.
Is the hose ATEX-approved?
The hose has antistatic and conductive qualification on both inner tube and outer coating, making it suitable for ATEX zone 22 (dust) installations. The factsheet does not however specify an explicit ATEX 2014/34/EU directive declaration. For formal ATEX installation we recommend cross-checking with your local risk assessment.
How long does the hose last?
Wear resistance 70 mm3 abrasion value (better than standard SILOFLAT's 100 mm3) typically allows the hose to last 3-7 years in continuous discharge operation with moderate powder media. Cement and lime powder are most abrasive; feed pellets and bulk substrate less so. Annual visual inspection of inner wall thickness is recommended.
Which couplings are recommended?
For large discharge installations (ID 152-305 mm), permanently mounted flange couplings or Bauer-style quick couplings with wear-secured rings are recommended. Standard worm-drive clamps are NOT sufficient on large dimensions. We typically fit couplings to the hose by arrangement.