Sludge Dryer Feed Screw Conveyor

Product Overview

The WLS420×8500 sludge dryer feed screw conveyor is a shaftless screw conveyor (WLS series) purpose-built as the feed stage of sludge drying lines. It receives dewatered sludge from filter equipment and delivers it continuously at a controlled rate into the inlet of a low-temperature sludge dryer. Installed at a -20° downward incline, the unit moves material downward under both gravity and screw thrust, forming a steady feed stream that prevents wet cake build-up and bridging at the dryer entry.

Wetted parts are selected for sludge duty: the trough and cover are 304 stainless steel, the spiral is manganese steel, and the trough is lined with a 10 mm UHMWPE liner, combining corrosion resistance, abrasion resistance, and low friction. The shaftless design suits high-moisture, fiber-laden sludge and is a typical configuration for dryer feed applications.

Technical Specifications

Construction and Design Highlights

Downhill Feed Arrangement

The -20° incline lets the spiral push material downward against gravity, creating a fixed elevation difference between inlet and outlet. The unit connects directly to the dryer inlet, avoiding cake build-up and compaction at the feed point.

304 Stainless Steel Trough and Cover

The trough uses 4 mm plate and the cover 2 mm plate, both 304 stainless steel for corrosion resistance in sludge environments. One φ450 mm outlet is on the trough side and one φ450 mm inlet on the cover side; both can be matched to the dryer inlet flange.

Manganese Steel Spiral

With a φ420 mm outer diameter, 350 mm pitch, and a 20 × 160 mm blade section, the manganese steel spiral delivers better wear resistance than carbon steel for sand-laden filter cake. The shaftless design advances fibrous and hair-like material without wrapping, a key requirement in dryer feed duty.

UHMWPE Trough Liner

A 10 mm ultra-high molecular weight polyethylene liner provides a low-friction, self-lubricating surface, reducing wear on both the spiral and the trough. The liner is a replaceable wear component, keeping the major overhaul interval practical in abrasive service.

Working Principle

The shaftless spiral is driven only at one end and rotates inside a U-shaped trough, advancing material continuously along the full blade length. With the -20° downhill arrangement, the gravity component acts in the same direction as screw thrust. The 8 m³/h figure is the design capacity; actual throughput varies with sludge moisture content and viscosity.

Applications

• Low-temperature sludge drying: receives filter cake from belt or plate-and-frame filter presses and feeds the dryer at a controlled rate
• Feed stage of sludge incineration and cement kiln co-processing lines
• Downhill metered conveying of other sticky, fiber-laden materials

Sizing and Maintenance Notes

Spiral diameter, length, incline angle, and inlet/outlet positions can be customized to the dryer feed elevation and site layout. During operation, monitor residual UHMWPE liner thickness and spiral blade edge wear regularly — sand-laden material accelerates wear.

Company Basic Introduction

Foshan Chengtong Machinery Co., Ltd., founded in October 2009, is located in Foshan City, Guangdong Province—one of China’s most important manufacturing and industrial hubs. The company is a comprehensive equipment manufacturer and technology service provider, specializing in the design, research & development, manufacturing, sales, installation, and after-sales service of bulk material conveying equipment and environmental protection equipment.

With more than a decade of steady development, Chengtong Machinery has grown into a large-scale and competitive supplier in South China, earning a strong reputation for product reliability, engineering expertise, and cost-effective solutions. Our products are widely used across multiple industries and have been successfully exported to Southeast Asia, Europe, Africa, and other international markets, serving customers with diverse operating environments and technical standards.

Driven by continuous innovation and strict quality control, we focus on providing stable performance, long service life, and practical engineering value. Chengtong Machinery is committed to becoming a professional technology-oriented enterprise that integrates equipment manufacturing with complete system solutions, helping customers improve operational efficiency and environmental performance.

For many years, the company has provided advanced, reliable, and reasonably priced equipment to numerous industries, including subway construction, railway construction, highway construction, bridge construction, municipal sewage and sludge treatment, river and lake dredging, garbage sorting, pulp and paper making, chemical industry, coal, metallurgy, mining, ports and docks, power, building materials, grain, cement, fertilizer, industrial salt, food, artificial board, transportation, and electronics. We have earned high praise from our customers and established excellent cooperative relationships. The company will continue to live up to the expectations and trust of our customers, providing high-quality equipment and attentive after-sales service, and is wholeheartedly committed to becoming a professional technology service company integrating R&D, manufacturing, installation, and after-sales service.