Bulletin 4391-B400S
EXACTOL
®
400 Series Tube Benders
5
Parker Hannifin Corporation
Tube Fittings Division
Columbus, OH
www.parker.com/tfd
Medium to Heavy Wall Tube Bending
Step 5: Select Slide Block Groove
Select the proper groove of the slide block for the outside diameter
of the tube (sizes are marked on the end of the slide block) and
position the slide block accordingly, against the slide block vise face
with the end of the block adjacent to the tube clamp of the radius
block. Lubricate the slide block to facilitate sliding. Then, advance
the slide block by means of the telescopic adjustment screw, to rest
snugly against the tube, but not with so much pressure as to pre-
vent the block from sliding easily along the slide block vise face.
Step 6: Using the Tie Bar (if required)
When it becomes difficult to hold distortion of the tube within 5%
because of deflection of the bender, place the tie bar over the
center post and the dowel pin. Always use the tie bar with heavy
wall tubing — sizes 7/8" or above.
Step 7: Bend the Tube
Tube bending is accomplished with ease by means of the crank
handle operating the mechanism through 60:1 ratio worm gear.
As the bend is being made, the slide block travels with the tube
and bears lightly against the radius block to form a true round die
enclosing the tube, providing a smooth, full cross-section bend. The
angle of the bend is indicated by the marks on the radius block. At
the completion of bend the desired degree mark will be in line with
the left side of the bender.
Step 8: After Bending the Tube
First, remove the tie bar, if in use. Next,
retract the slide block vise and remove the
slide block.
Step 9: Completed Bent Tube
Loosen the wing nut on the clamp, open, pull
the tube out from the radius block and lift up.
Your tubing is smoothly bent, without flatten-
ing or cracking.
To reset the tube bender, turn the worm
wheel shaft counterclockwise to disengage.
Turn the radius block back until the 0° mark
is at its original starting point. The bender is
then ready for inserting the next tube. Then
turn the worm wheel shaft in clockwise direc-
tion to re-engage the gear for the start of the
next bend.
Bends from 90° to 180° —
The 400 Series Tube Benders bend tubing up to 180° with ease. The procedure for
bends over 90° is the same as for bends to 90°. See Step 4.