Patent ID: 8016031

Claim:
An erosion resistant frac head, comprising: a frac head body having a top end with an axial port and a central passage that extends through the axial port and the frac head body, an annular shoulder that surrounds the axial port and is downwardly inclined with respect to the axial port at an angle of about 45° with respect to a central axis of the frac head body; at least two top entry ports welded in respective circular sockets machined in the annular shoulder, the at least two top entry ports being in fluid communication with circular bores that communicate with the central passage; the central passage including a convergence chamber where the central passage and the circular bores converge, an expansion chamber with a downwardly and outwardly inclined sidewall directly below the convergence chamber and a mixing chamber directly below the expansion chamber; and a bottom leg removably received in a bottom leg socket in the frac head body with an elongated pin thread that cooperates with a box thread of the bottom leg socket to secure the bottom leg in the bottom leg socket, and a lock nut threadedly secured to the elongated pin thread, the lock nut being tightened against a bottom end of the frac head body to lock the bottom leg in the bottom leg socket.