Is noc required for a huf flat from all members?what are opt

the share of the father in the HUF, upon his death, can go to his legal heirs, which will be their individual property , if the father has left behind him any female relative or a male relative claiming through such female relative , as in Class I of the schedule to the Act.

You are a coparcener in the HUF property. For obtaining loan on the said property, the Karta as a manager of HUF can apply and avail loan for the benefit of the property and the other members of the HUF  but it will be restricted to that property alone.  However, if you are compelled to give NOC, you may consult a local lawyer with the papers and take a decision.

a] Is noc required to be given.

Yes most of the Banks ask for NOC.

b]I do not want the burden of this mortgage to be transfered to me {being elder son} after his death.

And i do not want any rights whatsoever also.

Make partition 

c]so what precauutions shoud i take so that in future even after the karta, the mortage amount is not burdened on me as being the elder son.

Liability is of all Coparcener/Members of HUF

d]also the thing is from last several years my brother and him without informing us taking several loans against the property and this cycle of taking loans goes on and it creates huge burden on the family.

Make family division through court.

I do not want this and want to break this cycle. So is it necessary to sign this NOc.?