Question

Welding Problem A gas tungsten arc welding operation is used to create a fillet weld on both sides of a T-joint between two 1" thick medium carbon steel plates. The length of the T-joint is 36". The fillet weld as has a" legs. The welding operation will be carried out at a current 300 amps and a voltage of 20V. The welding process melts a volume of the parent material that is equal to 30% of the volume of the filler metal added to form the portion of the fillet weld that is exterior to the surface of the plates. The melting factor is 0.65. The welding rods (filler metal) are 20" long and 0.125" in diameter. Only a 15" length of the electrode can be consumed before the electrode has,to be changed. In gas tungsten welding 70% of the power is concentrated in a circle that is 3.5 mm in diameter and 90% of the power is concentrated in a circle fat is 10 mm in diameter. The cost of each welding rod is $1.50, and the labor cost of the welder is $65.00/hr. The cost of the equipment is $10.50/hr of operation. The cost of each of the component parts (steel plates) that are being joined is $15.40. The setup time per piece is 20 minutes. The welder does the setup work. I. Is the power density suffice for the welding process? 2. Calculate the rate of energy input generated by the power source. 3 Calculate the travel velocity of the welding operation Calculate the time per piece required to weld the T-joint . Calculate the cost per piece for the T-joint

Answer 1

Solution set叩 diagram. orn /h : 300 x 20 H 60oH Rate of inpot energyHifxf, xH Meing focor 65 6.S

P2 -tractional volume of 疒ïllev metal melt 30 s taken in account buse 30, of Paent materials met I 0 DO 60+30 3o, i 0 65 x 13 X H3coo 273 So, whichs eval to Tm34 Tm3683 K Enevgy veuired Pe onit Volome be u 3.33 x1ox Tm So, 3.33 o x 3683 e 45-168 J/mm3 0.0354 u 7385 4644 Jnch

A : CYoss Section orea of weld x base x height 2 2 inch Let be the velccity then, 3000 738514.4644 ㄧㄣˇ-. Hi-- UA o o325 inch sec 3) Time per Piece esuire to join Time taken to join weld t lengh of wel velociti b 0325 : 1l07.7se - o 3077 hrs

Volume of toeld - Vw A x length X 36 4.sinch3 = 0-184 inch : 24.446-25 Yds 4) Total time . t T: t C Setup time (Time to Change eiectrodes Time to veposition) Xn off loading time 68.46min

5 5) Cost Pe pece Total ostC Clabour Cost equiPment Cas t (n x cost or wekling Yod) 4Pazt Cose : 127.065