Assertion: hammer's piston | /r/AtLocation | top or bottom dead centre
Facets:
value: simultaneously
type: MANNER
Source sentences:
text: A two-cylinder locomotive has its two cranks "quartered" — set at 90° apart — so that the four power strokes of the double-acting pistons are evenly distributed around the cycle and there are no points at which both pistons are at top or bottom dead centre simultaneously.