Offers an efficient solution for welding extrusion cylinders used in the plastics, rubber, and chemical granulation industries.
These cylinders have long faced critical challenges: their inner walls endure prolonged exposure to high-temperature materials, severe particle wear, and media corrosion, while conventional carbon steel substrates have extremely short service life. Traditional manual overlay welding and single-tungsten electrode welding not only exhibit low efficiency but also suffer from issues such as uneven weld lines, insufficient penetration depth, and numerous defects in segmented irregular cavities and variable-diameter cylinder walls, significantly increasing maintenance and replacement costs. To address these challenges in irregular extrusion cylinder lining applications, we have developed a comprehensive automated overlay welding process using dual-tungsten cobalt-based wire, along with our proprietary control system, equipment, and welding guns. Utilizing ultra-high welding line speeds of 6,000–8,000 mm/min, 360-degree infinitely rotating CNC systems, and full-range adaptability for complex geometries, this innovation revolutionizes traditional wear-resistant layer manufacturing methods and provides an efficient wear-resistant overlay solution for extrusion cylinders, feed cylinders, spiral chambers, and other specialized components.
Core Hardware: Dual-tungsten electrode automatic welding equipment that breaks processing limitations through unrestricted rotation. Traditional cylindrical overlay welding systems typically employ fixed indexing rotors, requiring segmented processing and frequent start-stop cycles, making it impossible to weld workpieces with variable diameters, branches, or irregular internal geometries continuously in a single pass – resulting in significant time wasted on tool repositioning and angle calibration. This dual-tungsten electrode system features a continuous rotation CNC spindle capable of 360-degree uninterrupted rotation without angular limits or segmented welding seams. Equipped with an extendable welding torch mechanism, it can penetrate deep into long cylinders, hollow cavities, and branched irregular extrusion tubes, precisely reaching hard-to-access areas such as tube bottoms, diameter transition zones, and branching corners. The core innovation lies in synchronized dual-tungsten electrode welding: balanced thermal input from both arcs significantly increases per-pass welding width while reducing tool-pass counts by half compared to single-tungsten electrode systems. The entire unit operates under a closed-loop servo control system that dynamically adjusts rotational speed, torch feed rate, and wire feed speed in real-time, automatically optimizing welding parameters for non-standard extrusion tubes with uneven wall thicknesses or varying inner diameters.
Process Excellence: Achieving an ultra-high welding speed of 6,000–8,000 mm/min, with efficiency improved by several times compared to conventional industry standards where cylinder welding lines typically operate at 800–2,000 mm/min. Producing large-sized extruded cylinders previously required hours, creating significant bottlenecks in mass production. The dual-tungsten electrode cobalt-based welding wire system enables continuous welding speeds of 6,000–8,000 mm/min, delivering a 3–8-fold increase in welding efficiency and doubling the deposition rate. Synchronous dual-tungsten electrode feeding significantly enhances cobalt-based alloy deposition volume, substantially reducing processing time while maintaining equivalent wear-resistant layer thickness. Low heat input controls deformation: High-speed continuous welding minimizes substrate exposure to high temperatures, effectively preventing cylinder deformation and eliminating need for secondary alignment. Consistent weld profile: Uniform spiral weld patterns on inner cylinder walls with no unevenness, missed welds, or slag inclusion are achieved through high-speed rotation combined with dual arcs, ensuring uniform cobalt-based wear resistance layer thickness. For irregularly shaped, branched, or variable-diameter extruded cylinders, the system automatically adjusts rotation and welding gun speeds, with automatic speed reduction at corners and steps to maintain arc stability, balancing high production capacity with complex surface quality control and stable output for batch processing of non-standard components.
Advantages of Cobalt-based Welding Materials: Suitable for Strict Service Conditions of Extrusion Cylinders. Core failures in extrusion cylinders primarily result from high-temperature wear, chemical corrosion, and material adhesion or scratching. Cobalt-based alloys are industry-recognized superior welding materials for wear and corrosion resistance. When combined with dual-tungsten electrode high-speed automatic welding technology, the alloy layer achieves optimal performance: thorough fusion without porosity or cracks, uniform hardness of the wear-resistant layer, and resistance to continuous erosion by fillers such as glass fibers and calcium carbonate, thereby extending extrusion cylinder service life. The stable thermal field of the dual-tungsten electrode arc minimizes element consumption in the cobalt-based welding wire; the resulting weld exhibits high temperature resistance, resistance to adhesive materials, and tolerance to acid and alkali corrosion, making it suitable for processing high-temperature modified plastics, rubber, and chemical melts. High-speed welding reduces base material dilution, prevents carbon steel components from infiltrating the wear-resistant layer, preserves the inherent wear and corrosion resistance of cobalt-based alloys, and eliminates wear-induced spalling during short-term use.
Dedicated adaptation capability for non-standard and irregular workpieces, addressing key processing challenges in the industry. Most automatic welding equipment on the market is only suitable for standard straight cylinders and proves ineffective for forked extrusion cylinders, variable-diameter cylinders, or closed-bottom irregular cavities, often requiring manual supplementary welding with inconsistent quality results. Our comprehensive process is specifically designed for welding inside irregular extrusion cylinders: combining an infinitely rotating spindle with a telescopic deep-hole welding gun enables full coverage of various internal geometries including straight cylinders, conical cylinders, bifurcated double-cavity structures, stepped diameters, and closed bottoms. The CNC program allows customized adjustment of spiral weld bead spacing, penetration depth, and welding thickness, with automatic thickening of wear-resistant layers at wear-prone sections such as feed ends, discharge ends, and diversion corners. The fully automated operation minimizes human intervention, eliminating issues like uneven thickness distribution and insufficient local wear resistance inherent in manual welding, ensuring uniform performance of the wear-resistant layer across all extrusion cylinders.
Comprehensive Implementation Value: Cost Reduction and Efficiency Enhancement – Setting a New Standard for Extrusion Tube Wear Resistance Processing. Significant cost reduction: Ultra-high welding speed reduces processing time, markedly lowers energy consumption and labor costs per unit, and shortens delivery cycles for batch orders; Extended part lifespan: High-quality cobalt-based wear-resistant coatings minimize extrusion tube replacement frequency, substantially cutting maintenance costs for downstream extrusion equipment; Adaptability to All Non-Standard Orders: Infinite rotation capability combined with adaptive processes eliminate the need for complex tooling changes for irregularly shaped tubes, enabling flexible production of small batches and multiple models; In the manufacturing sector of wear-resistant components for rubber/plastic and chemical extrusion equipment, efficiency, quality, and customization capabilities are core competitive advantages. The dual-tungsten electrode cobalt-welded wire automatic welding process leverages ultra-high welding speeds (6,000–8,000 mm/min), 360-degree infinite rotation CNC systems, and customized processing solutions for irregular extrusion tubes, effectively addressing industry challenges such as low welding efficiency, difficult processing of irregular shapes, and inconsistent wear layer quality. Moving forward, we will continue refining deep-cavity interior wall welding technologies to deliver comprehensive automated cobalt-welded wire solutions with enhanced efficiency, stability, and performance for various specialized cavities, high-pressure barrels, and wear-resistant conveying tubes, empowering equipment manufacturers to achieve integrated upgrades in component quality, productivity, and cost-effectiveness.
