The occurrence of corrosion at heat affected zoneof a weld in stainlesssteel and corrosion prevention with a different welding process are to be explained. Concept introduction: Welding is a metal joining process by heating and melting a filler material and depositing at joints. Corrosion is a chemical reaction occurring due to reaction with atmospheric moisture and oxygen and results in the formation of oxides. Heat affected zones are the areas near the welded joint affected by heat and cutting operation. Properties and microstructure of heat affected area are changed due to the high heat generated during welding.

Question

! Required information Air at 25°C (cp=1006 J/kg.K) is to be heated to 58°C by hot oil at 80°C (cp = 2150 J/kg.K) in a cross-flow heat exchanger with air mixed and oil unmixed. The product of heat transfer surface area and the overall heat transfer coefficient is 750 W/K and the mass flow rate of air is twice that of oil. NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part. Air Oil 80°C Determine the effectiveness of the heat exchanger.

Answer 1

Question

Chapter 18, Problem 18.26P

Interpretation Introduction

Interpretation:

The occurrence of corrosion at heat affected zoneof a weld in stainlesssteel and corrosion prevention with a different welding process are to be explained.

Concept introduction:

Welding is a metal joining process by heating and melting a filler material and depositing at joints.

Corrosion is a chemical reaction occurring due to reaction with atmospheric moisture and oxygen and results in the formation of oxides.

Heat affected zones are the areas near the welded joint affected by heat and cutting operation.

Properties and microstructure of heat affected area are changed due to the high heat generated during welding.

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