| 摘要 |
<p>Metals which are molten up to 600 degrees C are metered by a device which comprises a conical steel valve seat with two grooves at an angle of 90 degrees C. In the grooves is a conical graphite plug which has a bore inclined towards the rotation axis. Specifically, when the plug turns, the upper bore end slides past the upper groove and, after a further rotation through 90 degrees, the lower end slides past the lower groove.</p> |
