Abstract: A safety brake unit for use in hydraulic or fluid power systems. The brake includes interleaved fixed and rotating discs held in compression by actuation pins and spring biased by a piston. As fluid pressure to the piston is relieved, the piston retracts to compress the discs and engage the brake.

Abstract: The sampling tube of the present invention is cost effective in its design and operates efficiently and relatively quickly in order to obtain a complete hydrogen sample although its application is not necessarily limited to the sampling of hydrogen content of a molten specimen.A sampling tube includes a pair of concentric tubes with an inner tube projecting outwardly and having a fusible end cap at an extending end which, when submerged in a molten sample, admits the molten sample into the evacuated tube. The inner tube has a substantially uniform cross-sectional diameter to freely allow the molten sample to fill the inner tube and solidify as the tube is removed. Diffusible hydrogen flows from the inner tube into the outer tube through a flow-reversing cap and passageway at the opposite end of the inner tube.