Abstract: An improved railroad trackwork spring wing frog assembly having a selectively releasable hold-open subassembly for the spring wing rail is provided with a combined compressible shock absorber and compression spring that are functionally connected to the assembly spring wing rail and to the assembly base plate, and that function to generate an opposing force in connection with opening movement of the spring wing rail and an augmented force in connection with closing movement of the spring wing rail.

Abstract: A railroad trackwork frog assembly is provided with a base plate, a spring wing rail supported by and movable laterally relative to the base plate, and a hold-down subassembly attached to the spring wing rail and to the base plate, the hold-down subassembly comprising, in combination with a horn housing, a horn element having a cross-section area moment of inertia about a transverse horizontal axis intersecting the cross-section area center of gravity that is smaller than the cross-section area moment of inertia about a transverse vertical axis intersecting the cross-section area center of gravity.

Abstract: .[.A method and apparatus for enclosing, controlling and suppressing the detonation of explosives in an explosion chamber is disclosed. The device comprises an elongate double-walled steel explosion chamber anchored to a concrete foundation, and having a double-walled access door for charging new workpieces, and a double-walled vent door for discharging the products of the explosion. The double walls of the chamber, access door and vent door are filled with granular shock damping material such as silica sand, and the floor of the chamber is covered with granular shock-damping bed such as pea gravel. Along the outside of the chamber are steel manifolds from which a linear array of vent pipes penetrates the double walls of the chamber, with each pipe terminating in a hardened steel orifice through which the explosion combustion products pass. Within the chamber, plastic polymer film bags containing water are suspended from steel wires over the explosive material, and at each end of the chamber..]. .Iadd.