what is the use and the locations of nacelle hinge bracket?
I'm assuming that you're talking about the part below. The part was changed from cast steel to titanium DMLS additive manufacturing technology.



Image from belement.co.il

The hinge is used to hold the engine nacelle cowling when opened. YOu can see four of them (older versions) on top of the open cowing in the image below:



Image from article.wn.com