Welding Case Study

CHAPTER 1:- INTRODUCTION

Company profile:

Surya steel tube limited, a branch of Surya group of industries, is leading in the manufacturing of line pipes in the country. It was established in 2005. At present Surya steel tubes is manufacturing long sheet saw, hot and cold finished pipes and tubes, ductile iron pipes.

Surya organization is one of the India's largest business groups. The company has diversified into various business areas in a professional manner.

The company's manufacturing plants are situated at many places across India.

The company's products have valuable demand in the market of India. The manufacturing capacity of the plant is 300000 tons per year. These pipes have cleared many quality checks there after transported all over

1.1 Problem Summary

The company is facing many problems related to Submerged Arc Welding (SAW) such as:-

• When the Quality checks are performed errors are detected in the thickness of the welded joint.

• As they need to perform Quality checks, the number of quality checks performed increases.

• The production process is time consuming as they need to perform no. of Quality checks.

• The workers perform manual welding at the start of the SAW; an initial start is must to initiate the Submerged Arc Welding of Spiral Steel Pipes.

The entire flow process of Spiral Steel Pipes Manufacturing includes different stages enlisted below:

Welding is one of the most widely used metal fabrication method in world wide.

Submerged Arc Welding (SAW) is broadly used in Spiral Steel Pipe Manufacturing its ease of operation, flexibility and efficiency make welding a variable and attractive process in modern industries.

Our project mainly focuses on to eliminate errors / faults in production of spiral pipes.

 Along with coil. The mill test certificates are verified for Mechanical, Chemical,

Corrosion (if applicable) and Dimensional characteristics with the customer’s requirements.

 Any lubricant that contaminates the weld bevel or the surrounding areas shall be removed before making the SAWH pipes.

 Width of the coil used for manufacture of HSAW pipes shall not be less than 0.8 times or more than 3.0 times specified diameter of the pipes.

 Chemical and Tensile testing samples are withdrawn from the coils on per heat basis and they are tested before manufacturing of pipe.

 If the result matches with customer’s requirements then Coils are accepted. After review of MTC the Coil no’s and their respective heat no’s are entered into the PC based Pipe tracking system (SAP) and coils are released for production.

Chemical analysis.

In these analysis various alloying element are tested and compared the standardized value of these element.

Mechanical testing

To check the mechanical properties of the material like tensile strength, hardness, fatigue, universal testing machine for tensile testing and brinell hardness machine for hardness