What is Welding Preheating ?

The phenomenon of heating the joint in the weld zone before the commencement of welding procedure is known as pre-heating. Normally it is applied by the use of ovens, flame producing torch, resistive heating elements and high frequency heating elements. It helps to eliminate welding interruption and several imperfections and set the joining phenomenon on smooth track. Why to use Pre-heat ? Following are the main reasons for using the pre-heat in a welding procedure. The use of Pre-heat, eliminates the surface moisture; consequently reducing the hydrogen induced cracking. It tweaks fusion and deposition of weld metal in a better … Continue reading What is Welding Preheating ?

Thread of Bolts – Basic Knowledge

When checking Bolt material coming, do you have feeling lose in the forest of BOLT & THEARD? We will help you to identify them accordingly via this topic! It has internal thread & external thread, can call male & female also. 1)  Thread direction: The helix of a thread can twist in two possible directions.: left hand & right hand. 2) Technical terms of thread: Type of thread: Pitch / TPI ( thread per inch ): – The pitch is the distance from the top of one thread to the next in mm. – TPI (Threads per inch) is used by … Continue reading Thread of Bolts – Basic Knowledge

CSWIP 3.1: Question with Answer and Explanation – Part 20

CSWIP 3.1 QUESTION AND ANSWER SERIES 1) A solid inclusion in a welder may be: Entrapped slag.  (answer) Entrapped gas. Lack of inter-run fusion. None of the above. This is “solid” not gas! 2) Which is the following is a planar imperfection? Lack of sidewall fusion.  (answer) Slag inclusion. Linear porosity. Root concavity. 3) For fillet welds it is normal practice in the UK and USA measure: Throat thickness. Leg lengths. ( answer ) Penetration depths. Both 1 and 3. Measure “Leg lengths” is easy checking on site. 4) Heavy porosity on the surface of some MMA welds made on … Continue reading CSWIP 3.1: Question with Answer and Explanation – Part 20

CSWIP 3.1: Question with Answer and Explanation – Part 19

CSWIP 3.1 QUESTION AND ANSWER SERIES CSWIP 3.1: Question with Answer and Explanation – Part 1 CSWIP 3.1: Question with Answer and Explanation – Part 2 CSWIP 3.1: Question with Answer and Explanation – Part 3 CSWIP 3.1: Question with Answer and Explanation – Part 4 CSWIP 3.1: Question with Answer and Explanation – Part 5 CSWIP 3.1: Question with Answer and Explanation – Part 6 CSWIP 3.1: Question with Answer and Explanation – Part 7 CSWIP 3.1: Question with Answer and Explanation – Part 8 CSWIP 3.1: Question with Answer and Explanation – Part 9 CSWIP 3.1: Question with … Continue reading CSWIP 3.1: Question with Answer and Explanation – Part 19

CSWIP 3.1: Question with Answer and Explanation – Part 18

CSWIP 3.1 QUESTION AND ANSWER SERIES CSWIP 3.1: Question with Answer and Explanation – Part 1 CSWIP 3.1: Question with Answer and Explanation – Part 2 CSWIP 3.1: Question with Answer and Explanation – Part 3 CSWIP 3.1: Question with Answer and Explanation – Part 4 CSWIP 3.1: Question with Answer and Explanation – Part 5 CSWIP 3.1: Question with Answer and Explanation – Part 6 CSWIP 3.1: Question with Answer and Explanation – Part 7 CSWIP 3.1: Question with Answer and Explanation – Part 8 CSWIP 3.1: Question with Answer and Explanation – Part 9 CSWIP 3.1: Question with … Continue reading CSWIP 3.1: Question with Answer and Explanation – Part 18