Rightchuffed

Hi I'm a newbie here..! I've recently purchased some Dundas 009 wagon kits and needed a little advice. In the kits are two 'L' shaped whitemetal pipes and I was curious as to the positioning of these. I have noticed on a lot of RTR wagons they are in the centre of the end but somebody told me that they go to one side , the side nearest to the brake lever ? Is this correct? I'm tempted to just position them in the centre. Also does the pipe run under the carriage. Also as a newbie , what are they ? Brake pipes ? and do I need to put them on. Finally the wagons do not have buffers on them is this common ? Sorry for all questions but i'm new to modelling trains .