sm_jamieson explained :
I have a gas hob to be fitted in the worktop of a standard fitted kitchen
with laminate worktop. Underneath is a 3-draw cabinet with 60mm pipe space
behind. The connection from the 22mm supply will be 15mm copper rising
vertically behind the unit in the pipe space, a right-angle elbow into the
cabinet and copper running just below the worktop for an inch or two, then a
15mm x 1/2" iron elbow connecting to male bsp taper on the hob.

What is the usual procedure to make the connection, since there is no access
behind the cabinet when the worktop and hob is being fitted ?

There's only a couple of inches in which to make the connection below the
worktop, so it seems that the pipe would have to be positioned very
accurately before the units are fixed in place.

Use a gas plug and socket, with flexible pipe. Mount the socket far
enough away from the hob, to get an easy sweep of the flexi pipe and
ensure there will be no contact between hot hob and pipe once all in
situ.

--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk