【转帖】standard for bom ballons
 

standard for bom ballons>
what is the standard when applying bom balloons to an assembly drawing that contain more than one of the same component?
the top picture in your attachment.
chris
solidworks 08 0.0/pdmworks 08
autocad 06
top? really? i've never seen it done that way.
i've seen both other methods.
the top one is what i have seen at several companies.
chris
solidworks 08 0.0/pdmworks 08
autocad 06
i've seen bottom the most, or similar to the middle example without the extra balloon. quantities are defined in the bom.
"art without engineering is dreaming; engineering without art is calculating."
i've never seen the top version either, but then i've never worked for a company which needed to adhere to an externally recognised standard. if it is the official standard it doesn't really make sense to differentiate between items. the bom states the quantity anyway.
madmango,
total quantities are defined on the bom. the same part, especially a fastener, could be used in several places on the assembly. often, i want to show how many screws are needed to attach a part. this can be hard to show on the drawing.
i have never seen it done the top way. i have seen the other two.
jhg
i guess i should be more clear. sorry.
the bottom is standard, calling out the qty next to the balloon. if another assy view or detail is called out on the dwg, the part can be called out again, but as reference illustrated in the top pic.
the middle pic should not be used.
chris
solidworks 08 0.0/pdmworks 08
autocad 06
i find it strange that the one which most clearly denotes which component is which and where it is, is the one which shouldn't be used.
having said that i normally only balloon an item once and without the quantity.
the way i've always done it is to use one balloon on one part and then have the quantities in the bom list. i don't show the same balloon on an identical part elsewhere in the assembly unless there's a chance it could get goofed up. i've never seen a repeated part in parenthesis though.
powerhound, gdtp t-0419
production supervisor
inventor 2008
mastercam x2
smartcam 11.1
ssg, u.s. army
taji, iraq oif ii
if i were checking my drafters work, i would reject the top and middle drawing for redundancy. the bottom is what i have always been taught is correct.