what is soldering and brazing ?

 Soldering

                     Soldering is the process of joining two similar or dissimilar metals by using a low melting alloy called solder.

     Solder is an alloy of tin and lead. it melts at low temperature(150 Celcius to 350 Celcius). the edges are not melted in this method.

         First the edges to be jointed are prepared and cleaned throughly. the parts are arranged in correct position.

           A flux like zinc chloride is applied at the edges to prevent oxidation. a welding torch or electric soldering iron is used for heating the work piece and melting the solder.

 The molten solder fills the edges  to be jointed. then joint is formed after solidification.

Applications

1) Connections in wireless set, Tv sets, etc.

2) Wiring joints in electrical connections, battery and other terminals.

3) Radiator brass tubes for motor car.

4) Copper tubing carrying liquid fuel, gas or air used in engines

5) Drain water pipes

Advantages

1) Low cost

2) The equipment is simple and cheap.

3) Effective sealing in fabrication.

Disadvantages

1) The joints are weaker.

2) It is not suitable for joining thick metals.

3) Joints are damaged under high temperature.

Brazing

        Brazing is similar to soldering. it is the process of joining two similar or dissimilar metals by using a high melting alloy called spelter. the spelter is a mixture of copper and zinc alloy.

 The melting temperature of spelter (60 celcius) is lower than the melting temperature of work piece. the edges of work pieces are not melted in this method.

      

                First the edges are prepared by filling or grinding. flux (borax) is applied and the work pieces  are assembled in correct position the work pieces are heated to a temperature below its melting point.

 The molten filler metal fills the edges to be jointed. then joint is formed after solidification.

Application

        Brazing can be done in brass, bronze, copper, steel and stainless steel.  brazing is used in radiator works, joining pipes with drums and tanks, joining carbide tips on tool shank, etc.

Advantages

1) Thin metal can be joined.

2) It is a fast process.

3) No distortion occurs.

Disadvantages

1) It is not suitable for joining thick metals.

2) The cost is more.

3) The strength of joint is less.