What Is Surfacing Welding

Have you been trying to extend the life and performance of your mechanical equipment? Surface welding is the only solution.

Using the surface welding technique, a metal coating resistant to wear, corrosion, and heat is deposited onto the surface of a workpiece, resulting in cost savings, increased service life, and improved product design.

This in-depth manual covers all aspects of surface welding, such as its equipment, classification, and range of applications. Whether you're a mechanical engineer or just interested in the newest welding technique, this article is a must-read!

WHAT IS SURFACE WELDING?

In "surfacing welding," a heat-, wear-, and corrosion-resistant metal coating is deposited on a workpiece's surface or edge. Surface welding can improve product performance, maximize material utilization, and increase part useful life.

Different surfacing methods are needed for different electrodes and workpieces.

Surface welding fixes damaged or worn-out parts.

APPLICATION RANGE OF SURFACE WELDING EQUIPMENT

Equipment utilized in the cement industry, including vertical mills, roller mills, screw conveyors, fans, and rotary kilns, often has automated surfaces. Convertors, rollers, blast furnaces, continuous casting equipment, and conveyor wheels can all use automated surfacing. Automated surfacing is used for coal mills, grinding rollers, boiler tubes, turbines, drain pipes, and gears in power equipment.

FEATURES OF A SURFACING WELD

In the process of "surfacing welding," materials with particular qualities are applied to the surface of a workpiece using welding techniques. Surface welding serves a different purpose than conventional welding techniques.

Surface welding alters the workpiece's surface rather than joining the pieces together to create a cladding layer with certain attributes, such as resistance to heat, corrosion, or wear, or to restore a workpiece's inadequate size due to wear or manufacturing mistakes. "repair" and "strengthening" refer to these two surface engineering applications.

Surface welding has the following benefits over other surface treatment techniques:

• High bonding strength and superior impact resistance are produced via metal-to-metal bonding between the surface layer and the base metal.
• The regularly used arc welding surfacing or flux-cored electrodes allow practical formula modifications. This makes it possible to modify the surfacing layer metal composition and performance. Different alloy systems can be created to adapt to various working environments.
• The surfacing layer's thickness can be changed from 2 to 30 mm, making it better suited to harsh wear.
• Surface welding reduces costs and improves the economy. It is possible to save a lot of precious metals when the workpiece substrate is constructed of common materials. In addition, the surface of the workpiece is welded with high alloys. When performing maintenance, a sensible choice of surfacing alloy and surfacing repair on the surface of a damaged workpiece can significantly increase the workpiece's service life. This can lengthen the maintenance cycle and save production costs.
• Because it involves expanding or shrinking pieces through welding or applying an alloy layer with unique qualities to the surface of the parts, surfacing technology is very practical. This kind of work can only be done by welding technicians.

How to clean welds faster with a wire brush? The wire power brushes are versatile and effective tools for weld cleaning. They remove surface impurities, such as rust or heat discoloration, without removing base material.

SURFACING WELD CLASSIFICATION

A form of fusion welding known as "surfacing welding" uses all fusion welding techniques. The table shows typical surface welding techniques. The two techniques most commonly used are electrode arc surfacing and oxyacetylene flame surfacing.

CLASSIFICATION OF POPULAR SURFACING TECHNIQUES

SURFACING WELD APPLICATION

The welding field's branch, known as "surfacing welding technology," offers various industrial applications. It is widely used in manufacturing, including tool molds and metal structures. It is also used in mining, transportation, metallurgy, power, agriculture, vehicles, and chemical and petroleum equipment.

Based on the intended use and operational circumstances of the workpiece, the following features of surface welding technology are illustrated:  

The service life of repaired workpieces is frequently longer than the service life of the original workpieces, in addition to functioning normally. This is so that modern surfacing repair techniques and materials can greatly enhance the performance of the original parts.

These repairs include resurfacing worn sections of agricultural machinery such as tractors, agricultural vehicles, transplanters, and harvesters. In addition, they include hot, cold, and profiled roll surfaces.

1. SURFACES THAT RESIST WEAR AND RUST

Material failure is primarily caused by wear and corrosion. One or more layers of wear- or corrosion-resistant material can be deposited on the surface of a metal workpiece to increase its wear and corrosion resistance, satisfy working conditions, and lengthen service life.

A bimetallic workpiece can be created by choosing distinct materials for the substrate and surfacing layer of the workpiece. This is because only the workpiece's surface layer needs to possess the necessary unique wear and corrosion resistance characteristics. Doing this increases the material's use and potential while conserving precious metals.

2. MAKE NEW COMPONENTS

Surfacing an alloy onto a metal substrate makes it possible to produce bi-metal machine components with a wide range of qualities. These parts' substrate and surface alloy layers each have unique qualities that can be used to meet distinct performance criteria. This method fully realizes material potential.

3. THE AREA OF APPLICATION FOR SURFACING

A. THE PRODUCTION OF MOULDS

• Plastic mold surfaces can be roughened to improve the aesthetic appeal and service life.
• Surface welding is recommended for mending a helmet plastic mold's separating surface.
• Surface strengthening is required for the diffuser cone of an aluminum alloy die-casting die.
• A mold cavity must be strengthened and repaired if it wears, scratches, or deviates from tolerance.

B. PLASTIC RUBBER

Repair rubber and plastic mechanical parts, including replacement of worn or out-of-tolerance rubber and plastic parts.

C. AEROSPACE

• Repair of turbines, turbine shafts, and aviation engine components.
• The rocket nozzle's surface and the aircraft's exterior panel components have been strengthened and improved.
• Improving or fixing the artificial satellite casing.
• Titanium alloy components are strengthened locally by carburization.
• Strengthening of an iron base superalloy through local carburization.
• Magnesium alloy surfaces are covered with anti-corrosion coatings like A1 and others.
• Surface welding fixes small dents in magnesium alloy items.
• Nickel base and cobalt base superalloy blade workpiece local surfacing repair, such as ablation of guiding vane and wear of blade tip and crown dampening surface.

D. ELECTRICITY USED IN SHIPS

• repairing electrical parts, resistors, bearing bushes, bearing sleeves, and other associated machinery.
• A locomotive's wheel and the track bottom are connected by a welded component.
• Creating and fusing copper-aluminum electrodes with metal oxidation characteristics and conductive rollers in an electroplating factory.

E. MACHINERY SECTOR

Correction of workpieces out of tolerance and repair of machine tool guide rails, different shafts, cams, hydraulic presses, hydraulic press plungers, cylinder walls, journals, rolls, gears, pulleys, mandrels for spring forming, plug gauges, ring gauges, various rolls, rods, columns, locks, bearings, etc.

F. FOUNDRY SECTOR

Fix casting flaws such as sand holes and air pockets in iron, copper, and aluminum, as well as mold wear.