Assertion: valve's ball | /r/CapableOf | rotate 90 degree
Facets:
Source sentences:
text: When the ball rotates 90 degree, the spherical surface will completely present in the inlet and outlet to close the valve, and block the flow of the medium.
text: When the ball rotates 90 degree again, the full ball mouth will present in the inlet and outlet to allow the flowing, and there is almost no resistance.