System for the continuous operation of a cold pilger rolling mill

In a cold pilger rolling mill having a reciprocating roll stand with repetitive cyclic periods of operation, an improved feed system arranged on the entry side of said mill for continuously feeding a shell along a passline of said mill between rolls in said roll stand to be reduced therebetween, comprising:

• feed carriage means positioned along said passline for displacement towards and away from said stand respectively corresponding to a shell feed starting position and a shell feed finishing position, said feed carriage means including first and second tandemly arranged feed carriages having chucks engageable with said shell for said advancement of said shell through said mill in said shell feed starting position of each carriage,
• feed screw means mounted in each of said feed carriages for effecting said displacement of said feed carriages relative to said stand and each said feed screw means having an adjacent end arranged in coaxial alignment relative to each other,
• first drive means driven in a timed relationship to said mill reciprocation and connected to said each feed screw means to impart a translational movement thereto to reciprocate said feed carriages together as a unit with said reciprocation of said rolling stand, and
• second drive means selectively driven by said first drive means including a gear unit connected to each said feed screw means of said first and second carriages and shaft clutch assembly means selectively engaging and disengaging said each gear unit so that upon said engagement superimposed on said reciprocation of said each feed carriage rotation is imparted to said feed screw means to move said first and second feed carriages separately and independently in unison in the same direction or in opposite directions relative to each other and said stand, and upon said disengagement rotation of said feed screw means is discontinued to maintain said feed carriages separately and independently in a fixed position,
• said gear unit for said second carriage which is closer to said roll stand than said first feed carriage includes thrust bearing means supporting and mounting said adjacent end of both said feed screw means in said coaxial alignment and effectively located between said two gear units in close proximity to said carriages to offset thrust loads on both said feed screw means and their said respective gear unit caused by said operation of said first and second carriages and said roll stand.