letang paul pdf

8/9/2019 LeTang Paul PDF

1/32

Advan c ed

Press Brake Technologies

John KempBystronic, Inc.


2/32

FABTECH Canada 2014

What you will learn about Why is Press Brake tooling so important

Why is this different than before Current trend

Future trends

Blank size and bend allowance

Bend and flatten

Short flanges

Tryout tools and other home remedies

Adjustable dies

Tool storage


3/32

Why is Press Brake tooling so important

Press Brake bending performance ultimately is determined by the

geometry of three critical points. The Upper Punch tip and theLower Die shoulders.

These are the only items that will ever contact the material!


4/32

Why is this different than before

Recent advances in Press Brake control systems have eliminated the

majority of manual operator machine tending.

Because of these high performance machines, manual operator tool

tending now consumes 90% or more of the total setup time.


5/32

What is the current trend

Almost every Press Brake sold today includes some sort of precision

ground, ergonomic tool handling system.

Traditional aligning and seating is eliminated!


6/32

What is the future trends

Better tool changing systems? Maybe?

Better tool shapes that are more versatile? Probable!


7/32

What difference does this make?


8/32


9/32

Blank size and bend allowanceWhat does tooling have to do with blank size?

This is how most systems assess bend allowance and blank size!


10/32

Here is the formula used by most CADsystems to assess the k-factor or neutral axes:

k = 0.65 + 0.5 * log (r / t)

k

r

In this formula to assess the k-factor, what 4 variables are missing?


11/32

Here is the formula used by most CAD

systems to assess the k-factor or neutral axes:

k = 0.65 + 0.5 * log (r / t)

k

r

Punch radius

Die Radius

Material type

Bend angle

In this formula to assess the k-factor,what 4 variables are missing?


12/32

What difference does this make?

Example:

Material Type = Cold Rolled Steel

Material thickness = .060”

Bend angle = 90 degrees

Punch Radius = .060”

Die opening = .500” Die radius = .060”

DIN bend allowance = .118”

Actual bend allowance = .114”

Results:

Without taking tooling and

material into consideration an

error of .004” is introduced at

step one!

Per bend!


13/32

Bend and flattenFlattening operations require a significant amount of force!

Modern tooling and machine features minimize setup times

Thickness Force TPF C Force TPF D

24

ga

.023" 3 .125" 10 .046"

20 ga .036" 4 .125" 11 .072"

18 ga .048" 6 .137" 15 .096"

16 ga .060" 8 .137" 16 .120"

14 ga .075" 14 .188" 20 .150"


14/32

Traditional hemming toolset method


15/32

Integrated hemming table method


16/32

How to “tool” for short flangesThe demand for lighter and more complicated products have driven

some flange lengths below the traditional tool limits!

Rocker dies are an effective flexible alternative to hard tooling


17/32

Sample rocker die in

action


18/32

How to “design” for short flangesThe demand for lighter and more complicated products have driven


Creative design is an even more effective alternative to hardtooling!


19/32


20/32

Relief cuts prevent bulging of the hexagonal holes during

the bend process


21/32


22/32

Tryout toolsDue to the demand for rapid prototyping, Press Brake tooling is sometimes

made from segments flame cut segments.

These tools are typically used for determination of special tool

shapes and not ideal not for mass production.


23/32

Take this process to

the highest level with

LASER cut quality

and many special

tools can be made

in-house, ondemand.


24/32

Adjustable dies Just-in-time, one-piece-flow and rapid prototyping effect heavy plate users

too. Adjustable V-dies do offer some advantages. Cost and complexity

however restrict many of their applications.


25/32


26/32


27/32


28/32


29/32

Home remediesThe demand for lighter and more complicated products have driven


Magnetic wear strips also help reduce excessive marking associatedwith short flanges.


30/32

Tool storageWith tooling setups consuming the majority of the total Press Brake

setup time, small improvements in tools handling can represent huge

productivity gains!

Many well organized and easy access systems are available.


31/32

Tools should be located at an ergonomic height.

Recessed slots should be provided to prevent

tool tipping.No drawers to open/close.

Visualization and random access to all tools at

once.Door can remain open during production

without obstructing operator workspace.

What to look for?


32/32

Thank

You

John KempBystronic, Inc.

letang paul pdf

Documents