equals sign for symmetry representation 1

[Karthi Vignesh]

which standard recommends using equals sign on either side of dimension for symmetry.

 

[chez311]

I've never heard of such a requirement. Could you provide an example of what you're talking about.

 

[mkcski]

Figure 4-33 in Y14.5-2018 (figure 1-35 in 2009) shows the "equal" signs. I think this is what the OP is referring to.

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[chez311]

Ah - that might be, however that would be utilization of the double bolded lines/"equals sign" to denote symmetry lines which are applied to lines in drawing views across which the part is symmetrical, and are not applied to dimensions as OP suggested.

Karthi - if this is indeed what you are referring to, these are noted in ASME Y14.5 and further clarification is provided in ASME Y14.2 - there may be an ISO equivalent as well. If not, as I said perhaps you could provide an example. See below for examples of symmetry lines.

Y14.5-2018 fig 4-33

Y14.2-2008 fig 3