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Rarely will your workups be actual.
Very seldom will the casting thickness the minimum size required. It's always thicker. (After all, they sell castings by the lb.) One structure that I was costing, had castings designed to be 38 mm thick. The joint was 1500 mm long plush run off tabs, a 45 double bevel and a 6 mm root. Switching to English measures for simplicity; gives us 79.71 cubic inches with the run off tabs or 22.17 lbs of weld. That is a lot of weld metal. Welcome to the world of over 300 ton capacity haul trucks.
The first castings come in and they are machined according to the print and concerned with joint angle and root floor. The man on the floor sets up the structure and guess what? You are called to the shop floor and find that castings are sold by the pound are way over thick. One of the castings is 47mm thick 1.85 inches. Just a little extra strength 9mm .38 inch extra built in.
This joint is 41mm 1.6” wide at the face. This will add a great deal of weld metal and time to this sturcture.
So we are using .052 ER70-S6 hard wire at 375 ipm wfs, 45 cfph 75/25 gas, 400 amp, 28 volt. Lets set the efficiency at 98%. The maximum width of a manual weld pass is limited by to .56 inch by the applicable code so we are looking at around 12-14 extra passes on this joint.
You were only about 35% off on the cost and the extra floor to floor time and it wasn't your fault
By the way, you should have caught this in the collaborative stage of design. Opps! Some companies still use “Over The Wall’” design. Shame on them. http://www.workstudy.in/ as an example.
The first thing you do is to show the work up to your boss. Join teams with engineering and purchasing to add a machining pass to both parts holding the thickness at 38 mm. Everybody is happy, especially the guy doing the welding and the bean counters. $328 per structure and 600 units a year=$196000 savings by adding one simple mill pass. And naturally we didn't subtract the extra machining time because that isn't our department. Not bad. Gold star for you. All this is a bit of a simplification but this is how it happens. …….