Sulphur Powder Screw Conveyor – Explosion-Proof, 304/316L

Sulphur Powder Screw Conveyor Overview

Sulfur powder is flammable and explosive, prone to static electricity, absorbs moisture and caking, and has a pungent odor, making it difficult for conventional equipment to handle. The Sulphur Powder Screw Conveyor uses physical isolation to lock the material inside a completely sealed casing. Rotating screw blades generate axial thrust, achieving horizontal or inclined displacement of the material. This continuous pushing motion prevents dust from dispersing into the air.

Sulphur Powder Screw Conveyor – Explosion-Proof, 304/316L design references ATEX Directive 2014/34/EU for equipment intended for use in potentially explosive atmospheres, and CEMA (Conveyor Equipment Manufacturers Association) standards for screw conveyor safety and dimensional practices.

Parameter	Specification
Product	Sulphur Powder Screw Conveyor
Explosion-Proof Rating	Ex d IIB T4 / Ex tD A21
Material (Contact Parts)	SS304 / SS316L, mirror-polished
Capacity	0.5 – 20 t/h
Conveying Angle	0° – 60° (inclined / vertical)
Operating Speed	40 – 70 rpm
Certification Reference	ATEX Directive 2014/34/EU, CEMA
Maintenance Cycle	18+ months (external bearings, SS316L)

 

In terms of material selection, all contact surfaces are constructed from SS304 or SS316L stainless steel, mirror-polished to prevent sulfur build-up and caking. Non-contact structural parts can be made of heavy-duty carbon steel with anti-corrosion coating. Designed for capacities between 0.5 t/h and 20 t/h, this conveyor meets stringent industrial safety standards in chemical, rubber, and pesticide plants.

Explosion-Proof Structure & Key Components

Because sulfur dust has an extremely low ignition temperature, mechanical safety is paramount in our structural design:

Explosion-Proof Drive Unit: Equipped with Ex d IIB T4 / Ex tD A21 explosion-proof motor and reducer with sealed junction boxes.

Air-Purged Double Seals: External mounted bearings paired with packing seals and continuous air-purge lock to eliminate friction heat and dust ingress.

Electrostatic Discharge (ESD) Protection: Copper conductive strips across housing flanges and shaft-grounding carbon brushes continuously dissipate static charges.

Directional Pressure Release Vent: Burst vents on top of the housing instantly release abnormal pressure in a controlled direction.

Key Benefits of Dahan Sulphur Powder Screw Conveyors

Using our specialized sulfur conveyor system transforms workshop safety and operational stability:

1. Zero Dust Leakage: Completely sealed pipeline prevents sulfur dust escape, meeting international occupational health standards.

2. Low-Speed Thermal Control: Operating speeds are kept within 40–70 rpm to minimize friction heat and prevent sulfur melting/agglomeration (melting point ~115°C).

3. Long Maintenance-Free Cycles: Externalized bearings and acid-resistant SS316L extend the spare parts replacement cycle to over 18 months.

Process Integration Solutions

In rubber vulcanization or pesticide compounding systems, the inlet connects directly via flexible anti-static joints to upstream Bulk Bag Unloaders or sulfur grinders. The discharge outlet features a downward slope flanged to downstream mixers or reactors, equipped with pneumatic isolation valves to prevent downstream steam or acid vapor backflow.

Application Case: Rubber Vulcanization Plant, Southeast Asia

A rubber manufacturer required sulphur powder transfer from bulk bag unloaders to mixing reactors with zero dust leakage. Installed 3 units of Ex d IIB T4 rated conveyors with 5 t/h capacity at 30° incline. Result: dust leakage eliminated, maintenance interval extended to 20+ months.

Rigid vs. Flexible Screw Auger Conveyor for Sulphur

Characteristic Comparison	Rigid Screw Conveyor (Recommended)	Flexible Spring Screw Conveyor
Core Structure	Solid central shaft with welded SS304/316L flights.	Shaftless, driven by a rotating spring coil.
Conveying Path	Straight-line (horizontal, inclined up to 60°, or vertical).	Curved routing around obstacles.
Sulfur Adaptability	Fixed clearance, low friction heat, minimal blockage.	Spring runout generates high friction heat, melting sulfur.
Safety Rating	High — Certified explosion-proof and anti-static.	Moderate — High risk of static build-up.

Selection Conclusion: For flammable sulfur powder, rigid tubular screw conveyors with central shaft support provide significantly higher operational safety and prevent friction-induced melting.

Sulfur Powder Screw Conveyor Specifications

Model	Screw Dia.	Max Capacity	Max Length	Motor Power	Explosion-Proof Grade
AUG-S159	159 mm	1.5 t/h	≤ 6 m	1.5 - 2.2 kW	Ex d IIB T4 / Ex tD A21
AUG-S219	219 mm	5.0 t/h	≤ 12 m	3.0 - 5.5 kW	Ex d IIB T4 / Ex tD A21
AUG-S273	273 mm	10.0 t/h	≤ 15 m	5.5 - 7.5 kW	Ex d IIB T4 / Ex tD A21
AUG-S325	325 mm	20.0 t/h	≤ 20 m	7.5 - 11.0 kW	Ex d IIB T4 / Ex tD A21

How Much Does a Sulphur Powder Screw Conveyor Cost?

Prices depend on stainless steel grade, explosion-proof level, and length:

SS304 Standard Model (Dia 159mm, 3m): $3,200 – $5,000 per set.

SS316L Explosion-Proof Model (Dia 219mm, 6m with water jacket): $6,500 – $9,800 per set.

Heavy-Duty SS316L Model (Dia 325mm, 8m): $12,000 – $18,500 per set.

Need ATEX Certified Design or Water-Cooling Jacket?

Our engineering team can design custom sulfur conveying systems with CAD drawings within 24 hours.

Frequently Asked Questions

What is the lead time for custom explosion-proof sulfur conveyors?

Standard SS304 models take 10-15 working days. Custom SS316L models with ATEX certifications take approximately 20 working days.

How does your screw conveyor prevent sulfur dust explosions?

The sulfur powder screw conveyor uses a fully enclosed casing for dust prevention, external air seals, electrostatic grounding, Ex d IIB T4 explosion-proof motors, and low operating speeds to prevent friction heat.

Can water-cooling jackets be added for high-temperature workshops?

Yes. We can weld a double-layer water jacket along the conveyor tube wall to circulate cooling water, keeping sulfur temperatures well below its melting point.

What material is used for the screw and casing in contact with sulphur?

All contact surfaces use SS304 or SS316L stainless steel, mirror-polished to prevent sulfur build-up and caking. Non-contact structural parts use heavy-duty carbon steel with anti-corrosion coating.

What is the recommended conveying speed for sulphur powder to prevent melting?

Operating speeds are kept within 40–70 rpm to minimize friction heat. This is well below the speed that would generate temperatures approaching sulfur's melting point of approximately 115°C.

The Sulphur Powder Screw Conveyor's technology lies in its airtight design for disaster prevention and mechanical wear control. Through a combination of external bearings, multiple air seals, whole-machine electrostatic discharge, and explosion-proof electrical components, hazardous dust is contained and flows smoothly within the metal pipes. Clearly defining parameters such as upstream feed rate, downstream receiving height, and material corrosion level are prerequisites for customized production and obtaining accurate system quotations.