Posts tagged auto shredder

May 7, 2017

Used Scrap Metal Ferrous Shredding System for Sale

Tom Stanek

An effective energy efficient metal shredding line up

Update: This unit has been sold  

5000 HP Ferrous Scrap Metal Shredding System for sale.  The heavy duty shredder box is 88 x 101 inch with 4 inch thick walls.  This is a complete package with infeed conveyor, ferrous line, motors, pumps, water injection, and coolers.  Many extras such as power systems and a computer managed over sized double feed roll allow this machine to shred serious volume in a compact package.  150 tons per hour ferrous out production.

The primary drive is a 5000 HP (3730 KW) A/C Wound Rotor Motor.  The hard charging Schorch motor keeps churning day after day.  Dual axial pole magnets, cyclone air cleaning system, and split picking station allow for extremely clean and dense ferrous scrap.

Slip Power Recovery Drive is included.  Motor rotor current is managed in a switchable duel system using either liquid rheostat or solid state SPR drive.  The SPR efficiently runs the motor with greater power, cooler temperatures, more tons per hour, while allowing less flicker and inference with local electrical grid, thus greater options for relocating the installation.  Comes with heavy duty GE transformer (25kV/4160), power factor capacitors, and many extras that take the added cost out of relocating the machine.

The system includes infeed conveyor, shredder dampening springs, under mill oscillator, conveyors, magnets, water injection system, de-dusting air cleaning zee box, dual picking station, stacking conveyor, and non-ferrous radial stacking conveyor.  Many spare casting wear parts and spare parts are available.  The motor room is protected by an air filtration system.  Roof mounted coolers, control cabin, infra red camera, and shredder management computer round out the system.  Non-ferrous separation system as NOT part of this package.

An effective and energy efficient equipment line up.  A very complete system, well cared for with low tons on the machine.   This unit represent an excellent opportunity for a new installation or if you are looking to replace an aging shredding plant.

Spare motor and rotor available as extras.

Contact us at for more details.  Serious inquires only.


December 6, 2012

Shrink Fit Coupling Removal

Tom Stanek

High torque drive couplings usually involve a shrink fit.  The coupling is machined with a smaller diameter than the mating shaft.  The coupling is heated 300-400 degrees hotter, expands and can be slipped onto the drive shaft.  It cools, shrinks in diameter, and a tight mechanical fit is accomplished (with keyways or splines as well).

You may have to remove a shrink fit coupling when changing out drive motors or rotors.  Your manufacturer’s rep can get you some advice on the pulling force and strength needed for a successful removal.  Without adequate set up, you’ll bend or snap rods, and be left with hours of time to shed enough heat before you can work on the unit again for another attempt.

  1. You’ll need a lifting device and rigging to hold up several hundred pounds of coupling as you slide it off the shaft.
  2. 6 to 8 full diameter threaded rods seated full depth in your coupling’s end holes, and a few dozen nuts.  Use grade 8 rod (150 ksi tensile) to give you full strength and minimal elongation.
  3. 2 inch thick backing plate
  4. 12-20 tons of jacking force.  Hydraulic jack (s) and enough jack stroke to pull off the coupling.  This may require a stub shaft insert if you the jack stroke is less than the coupling length.
  5. Torches and heating tips.  Rosebud heating tips of proper size (8 or 10) are important.  Using both propane and oxy acetylene torches is wise.  Acetylene burns hotter and there is limited space to apply torches to the coupling.  Make sure you have enough gases on hand in case you need more than one attempt to remove the coupling.
  6. Fire retardant blankets
  7. A clean and clear work area
  8. Fire fighting gear, a clear work area, and heat resistant PPE for personnel
  9. Your safety program may require a hot work permit

The key item is to heat the coupling quickly, so it expands before the shaft it’s mounted on heats up and expands as well.  The difference in temps for allows for expansion.  Also, excessive heat in the shaft can lead to damage of bearings, seals, and other components.


Always let things air cool.  Never cool with water or gases like a CO2 fire extinguishers.  If you have a fire emergency, do what you need to do to minimize loss of property or life.  However quenching with water or anything else would likely damage the coupling or shaft steel.