Thermit Welding — Typical Industrial Applications Thermit (exothermic) welding is commonly employed for which of the following tasks in heavy fabrication and maintenance?

Introduction / Context:
Thermit welding uses a highly exothermic reaction between aluminum and iron oxide to produce molten steel, which fuses parts without an external power source. It is widely used in field conditions where large, rigid components must be joined or rebuilt.

Given Data / Assumptions:

• Process: thermit welding with crucible and mold around the joint.
• Application scale: heavy sections and field repairs.
• Desired outcomes: strong metallurgical joints and material buildup.

Concept / Approach:
The process excels for massive components where mobility, simplicity, and high heat input are advantageous. The molten thermit steel fills the prepared joint gap and solidifies, creating a robust bond suitable for dynamic service such as rails or heavy frames. It can also rebuild broken or worn features like gear teeth and shear edges by casting-on and subsequent machining.

Step-by-Step Solution:
Identify typical tasks: rail joints, frame repairs, and feature restoration.Assess process capability: intense localized heat and cast-on potential.Map tasks to capability: all listed operations are feasible and common.Select the most inclusive correct option.

Verification / Alternative check:
Railway permanent-way maintenance globally uses thermit (aluminothermic) welds for rail joints.

Why Other Options Are Wrong:
Choosing any single task underestimates the broad applicability of thermit welding.“None of these” contradicts standard practice.

Common Pitfalls:
Confusing thermit welding with fusion arc welding; thermit is a casting-like process using chemical heat.

Final Answer:
all of the above