The advanced equipment used for Folding processess is amongst the best of it's kind in the world, the tooling Folding uses has improved over the years to virtually eliminate distortion when Folding.
St Anns Sheet Metal Company can service all your Folding requirements with our on site press brakes, allowing us to form simple shapes right through to the most intricately folded precision components. We are also able to offer a high volume rolling service using our precision rolling machines.
Our brake presses are:
- AMADA ITS 50 Tonne 2 MTR
- PROMECAM 80 TONNE 2.5 MTR x2
- PROMECAM 50 TONNE 2 MTR x2
- PROMECAM 25 TONNE 4 FT
We hold a library of tools suited for a wide range of folds, bends and folds, these tools enable St Anns to achieve exceptional accuracy and quality. Folding ranging from standard 90 bends, deep Folding for enclosures, L-shapes and hemming through to radius Folding and radius rolling are all professionaly achieved. Each type of folding requires different tooling (Tools are otherwise known as Dies)
Machines used to bend metal are called a press brakes also known as CNC Brake Presses. They are able to fold sheet metal which is just a few mm long through to many metres long.
These presses contains a V shaped groove, called the die. The upper part of the press contains the punch that presses the sheet metal down into the die (down forming), causing it to bend. There are several techniques used, but the most common modern method is air Folding.
In Air Folding the die has a sharper angle than the required bend and the upper tool is very precisely controlled during its stroke, pushing the material down the required amount to bend it. A general purpose air Folding machine has a Folding force available of around 25 tonnes per metre of length.
The opening width of the lower die is typically 8 to 10 times the thickness of the metal to be bent, the inner radius of the bend formed is determined by the lower die width. Typically, the inner radius is equal to 1/6th of the V width used in the forming process.
Some bottom tools are adjustable, so, by using a single set of top and bottom tools and varying press-stroke depths, many different profiles and products can be manufactured. Different materials and thicknesses can be folded adding to the advantage of the flexibility of air bending. Often air folding requires fewer tool changes resulting in higher productivity.
Precise and accurate
Press brakes usually have a back gauge to position depth of the bend along the workpiece, this backgauge can be computer controlled to allow the operator to make a series of bends to a component to a high degree of repeatable accuracy.
Simple machines control only the backstop, more advanced machines control the position and angle of the stop, the height and positioning of reference pegs used to locate the material. These machine also record the exact position and pressure required for each Folding operation, allowing operators to achieve perfect 90 degree bends across multiple operations.
Roll Forming Machines
Roll Forming metal is a continuous Folding operation, long lengths of metal are fed through consecutive roller stands, each set of rolls the metal passes through perform an incremental part of the overall bend, the desired cross-section profile is obtained once the process is complete.
Roll forming is ideal for producing components with long lengths and producing open profiles, and is ideal for producing large quantities. Roll formed sections have many advantages, they are often lighter, have thinner walls and yet are stronger than 'extrusions' of similar shapes. Roll forming machines are useful for producing longer lengths, large batches they can produce shapes of different sizes and material thicknesses using the same rolls, as the distance between the rolls can be adjusted.
Roll-forming lines can be set up with multiple configurations, sections can be punched and parts removed in one continuous operation.
For cutting a component to length, lines can be established using pre-cut die's where a single blank is passed through the roll mill or post-cut die's are utilised, where the profile is removed after the roll forming process.
Features such as holes, notches, embossing or shearing may be achieved in one continuous operation by setting up a roll forming line with multiple configurations. Features such as these can be done pre-punch (before roll-forming), mid-line(during roll-forming) or a post punching application (after roll-forming).
Some roll-forming lines will incorporate only one of the above 'punch' or 'cut-off' applications others may incorporate most or all of the applications in one line., they really are so versatile.
In Roll Forming a variety of cross-section profiles can be produced, with each profile requiring a carefully crafted set of roll-tools.
Design of the rollers starts with a flower pattern, which is the sequence of profile cross-sections, one for each stand of rolls. The roll contours are then derived from the profile contours. Due of the fact that the cost of the roll sets is high, simulation is often used for validating the designed rolls and to optimize the forming process. This simulation validation minimizes the number of stands and limits the material stress present in the final product.