Has anyone ever used safflower oil on moulded biscuit dough? After replacing sunflower oil by it in a trial (1:1), it was impossible to extract dough pieces in good condition (they seem to be dry and heterogeneous). Should I make changes in oil quantity?
I don't know safflower oil, but you describe a common problem when there is little fat in the recipe or you don't use a remolding agent like lecithin. Are you using it? If yes add some more if not add 1% of the fat.
Using sunflower oil or safflower oil in short dough moulding variety will have very short shelf life and highly prone to rancid. As these oils are unsaturated oil and very highly prone to oxidation if any chance there. Normally for moulding variety with reasonable high fat with respect to semi sweet or cracker biscuits should be careful in selecting the fat to be used. Instead using these two oils I suggest use palm oil which will give you perfect biscuit as well shelf life.
In theory sunflower and safflower oil should give the same result on your dough consistency and so on dough handling. Possibly you have a critical recipe, which results in variation in dough consistency.
Most probably your sunflower is has a different fat spectrum than safflower. (SFA-MUFA-PUFA) therefore adding some emulsifier as per suggestion of mr Pimper is correct. 1-1,5% of the fat level is quite common to start with.