my slides for Straightening Processes (Press Straightening)

1. Press Straightening

2. Straightening
• In metalworking, the elimination or reduction of
unnecessary curvatures in metal items by the application
of external forces. Straightening is used in the
production of sheets, tubes, rails, beams, and other
milled items. It is also used, although less frequently, in
metal consumption, for example, by forges and metal
structures shops.
• Distinctions are made between press straightening
(batch straightening) on straightening presses, parallel-
roll straightening (continuous straightening) on
straightening machines, and rotary straightening by
untwisting and stretching on rotary straightening
machines. For some cases, Straightening could be
applied manually using tools.

3. Press Straightening
It is an innovative solution in the field of
straightening technology with hi-tech Hydraulic
Straightening Presses. This press can efficiently
undergone a procedure from a round, flat and
profile material of different hardnesses. This
could be used for either C-frame presses or
Gantry style presses, Straightening presses are
mainly used for straightening medium or thick
sheet, section, tube or round bar.

4. In Press Straightening, the item to be
straightened is placed on two supports and force
applied to the uneven surface causes
elastoplastic deflection. Major disadvantages are
the low precision of the straightening operation
and the significant residual stress.

5. Straightening Process Description
The workpiece or the part is manually loaded
into the Straightening Press. The part is clamped at
centers (or rollers) and than rotated to measure the
straightening by using dial indicators. When the
upper point is rotated vertically, the lever is pressed
down causing the part to flex. After each and every
stroke, dial indicator shows the straightness of the
part so that operator can alter the depth of stroke
until the straightness is within tolerance range.
Repetition of the process occurs at determined
points to achieve the specified straightness or TIR
(Total Indicated Runout).