Application of Tubular Wire Surfacing Technology in the Nonwoven Fabric Industry

Literature Overview

This study explores the application of tubular wire (flux-cored wire) surfacing processes in the nonwoven fabric industry, where components such as roller surfaces, calender rolls, and forming drums are subjected to severe wear and corrosion conditions. The nonwoven fabric industry involves continuous production processes where equipment downtime is extremely costly. The study investigates how tubular wire surfacing can extend component life, reduce maintenance frequency, and improve overall production efficiency.

Core Technical Discussion

Tubular wire surfacing, also known as flux-cored arc welding (FCAW) surfacing, utilizes a hollow wire filled with flux and alloying elements. The flux provides shielding gas and slag protection during welding, while the alloying elements in the flux core contribute to the composition of the overlay layer. This process is well-suited for surfacing applications because it offers high deposition rates, good process stability, and the ability to deposit alloy compositions that are difficult to achieve with solid wires.

Process Characteristics for Nonwoven Industry Applications

Parameter	Typical Value	Application Context
Wire diameter	1.2–1.6 mm	Standard surfacing operations
Current range	180–350 A	Depending on wire type and position
Voltage range	22–30 V	Self-shielded or gas-shielded
Deposition rate	3–8 kg/h	Significantly higher than solid wire
Travel speed	200–500 mm/min	Mechanized application
Preheat temperature	100–250 °C	For carbon steel and low-alloy steel substrates
Interpass temperature	Below 250 °C	To prevent grain coarsening

Material Selection and Overlay Design

The study addresses the selection of tubular wire compositions for different components in the nonwoven fabric industry. Calender rolls typically require overlay layers with high hardness and wear resistance, often achieved using high-carbon high-chromium compositions. Forming drums may require corrosion-resistant overlay layers, particularly in environments where moisture and chemical additives are present. The study recommends specific wire compositions based on the operating conditions of each component type.

For wear-resistant applications, tubular wires containing 12–25% Cr, 3–6% C, and Mo or V additions produce overlay layers with hardness values of 500–700 HV. These compositions form hard carbides (Cr7C3, Cr3C2) that provide excellent abrasion resistance. For corrosion-resistant applications, austenitic stainless steel tubular wires (309L, 310L composition) produce overlay layers with good resistance to acidic and alkaline environments.

Performance Comparison of Overlay Compositions

Wire Composition	Hardness (HV)	Wear Resistance	Corrosion Resistance	Typical Application
12Cr-3C	550–650	Excellent	Moderate	Calender rolls
20Cr-5C-Mo	600–700	Excellent	Low	High-wear zones
309L austenitic SS	200–280	Moderate	Excellent	Forming drums
310L austenitic SS	200–260	Moderate	Excellent	High-temperature zones
Ni-based (Inconel type)	250–350	Good	Excellent	Corrosive environments

Engineering Implementation and Quality Control

The study provides practical guidance for implementing tubular wire surfacing in production environments. Key considerations include:

Surface preparation is critical; the base metal surface should be ground to a smooth finish with a roughness of Ra ≤ 6.3 μm to ensure good bond strength.
Wire storage and handling must prevent moisture absorption, which can lead to porosity and hydrogen-induced cracking.
Welding parameters should be optimized for each wire type and substrate condition through systematic qualification testing.
Post-weld inspection should include hardness testing, bond strength testing, and non-destructive examination (MT or PT) to detect surface defects.

Quality Control Checklist

Inspection Item	Method	Acceptance Criteria
Surface quality	Visual + PT	No cracks, porosity, or undercut
Hardness	Vickers HV10	Within specified range ±50 HV
Bond strength	Peel test	≥ 40 MPa
Overlay thickness	UT or sectioning	Within tolerance ±0.5 mm
Dilution rate	Spectroscopy	Within 30–50%

Study Insights and Implications

The application of tubular wire surfacing in the nonwoven fabric industry represents a practical example of how advanced welding technologies can be adapted for specific industrial needs. The high deposition rates of FCAW surfacing make it economically attractive for large-area component repair, while the flexibility of wire composition allows for tailored overlay properties. However, engineers must be aware of the limitations of this process, particularly the higher dilution rates compared to solid wire processes and the potential for slag inclusion defects. The study reinforces the importance of systematic qualification testing and quality control in ensuring reliable overlay performance. For industries with continuous production requirements, the ability to quickly repair and refurbish worn components using tubular wire surfacing can result in significant cost savings and reduced downtime. This study provides a valuable reference for engineers seeking to optimize maintenance strategies in the nonwoven fabric and related industries.