This type of engine could do several jobs.
Whilst it could have been used at sea, it never had the additional capstan ends that many marine winches had.
It could and did work as a shaft winder but would have been equally at home as a main and tail haulage engine.
Morlock, have a look at the main and tail haulage system and you will see that two drums are required, one pulling and one braked.
B Eng, whilst the actual shaft may be imaginary, the headframe (visible from the A6 ), is not.