considerations for choosing a press brake lenmark industries

Looking for a brake press? Read Lenmark's quick guide to take you through the most important criteria for choosing:

What is a brake press?

A press brake is a metalworking tool used to bend various types of metals, such as stainless steel and mild steel. It employs hydraulic or electric technology to exert force on a metal workpiece, enabling precise bending based on specific characteristics like tensile strength, thickness, and length. Press brakes play a vital role in metal fabrication, offering flexibility in bending operations. Whether hydraulic, electric, or hybrid, these machines are essential for achieving accurate bends in metal sheets. Incorporating advanced features like back gauges and angle control, press brakes enhance efficiency and safety in metalworking processes.

Brake presses are essential for a variety of industries, including automotive, metal artwork, furniture, etc; they are typically used to create parts such as brackets, metal containers, automotive panels, hinges, and more. 

About CNC:

At Lenmark, we sell MVD CNC Press Brakes. CNC stands for computer numerical control; this is a system that guides the bending process, allowing for hyper-precision and speeding up the entire process. 

 Advantages of CNC press brakes include: 

  1. Versatility to handle diverse materials and fashion intricate shapes.
  2. Reduced material wastage when compared to traditional bending methods.
  3. Enhanced precision and accuracy attributable to the CNC controller.
  4. Various automation options contributing to heightened productivity.

Step 1: Determine Materials Characteristics

The first thing you'll need to do before choosing a press brake is to determine the type of metal you need to bend - this is going to be crucial in determining your selection. Here's what you should know about the metal you'll be working with before making your decision:

  1. Tensile strength
  2. Thickness & length of metal
  3. The press brake's folding or bending length
  4. The width of the V
  5. Inner radius of the parts

Step 2: Understand Types of Press Brakes

Hydraulic press brakes

Hydraulic Press Brakes utilize hydraulic cylinders, allowing for higher bending capacities than electric or hybrid press brakes. These machines are typically stronger and thus suitable for a wider range of bending operations. Hydraulic brakes tend to have a lower initial cost than electric or hybrid machines. 

At Lenmark, we're proud partners with MVD Machinery. MVD manufactures an industry-leading line of hydraulic press brakes that allow customers to achieve efficiency, precision, and speed. Check out all of the MVD products we sell here. All MVD press brakes are CNC, allowing for a higher level of precision, lower material wastage, flexibility to create complex shapes and handle a wide variety of materials, and giving the user a wide range of automation options to help increase productivity. 

Choose from a variety of series:

  1. A-series
    • 3-axis standard (can be configured up to 4 axis
    • Stroke: 210 mm
    • Throat depth: 410 mm
  2. B-series
    • 3-axis standard (can be configured up to 8 axis
    • Stroke: 260 mm
    • Throat depth: 410 mm
  3. C-series
    • 3-axis standard (can be configured up to 8 axis
    • Stroke: 310 mm
    • Throat depth: 410 mm
    • Manual anti-deflection crowning system
  4. D-series
    • 3-axis standard (can be configured up to 8 axis
    • Stroke: 410 mm
    • Throat depth: 510 mm
    • Motorized CNC anti-deflection crowning system

Hybrid press brakes

Hybrid systems offer a blend of features, employing a mix of different features from both all-electric and hydraulic press brakes. Hybrid brakes will usually use hydraulics for bending operations, but may have servomotors rater than gear pumps. 

Hybrid systems are generally considered to have high accuracy (comparable to all-electric), a low running operating cost, are typically a cheaper options than an all-electric press brake, and are eco-friendly. 

Electric press brakes

Electric press brakes utilize servomotors rather than hydraulic cylinders. Electric press brakes can come with less maintenance, but are typically more expensive than hydraulic options. Electric brakes also have limited tonnage and may not be as suitable for high-volume production. They are also generally considered to be relatively inexpensive to operate. 

Electric press brakes may have some tonnage limitations compared to hydraulic; electric brakes come with high precision and speed, but typically for thinner metal sheets. If you're looking for a high tonnage machine, you may want to consider hydraulic. 

Step 3: Choose Bending Type

Air Bending

In the air bending technique, a vertically adjustable punch exerts force on the metal sheet within a V-shaped or U-shaped die groove. Notably, the punch doesn't reach the bottom of the groove, allowing a gap or air space to remain. This design permits varying the depth of the punch within the groove to achieve different bending angles.

The versatility of air bending lies in its ability to generate various bending angles using the same punch and die tool, making it the preferred method for sheet bending in many applications.

However, due to the incomplete compression between the punch and die, the bending force in air bending tends to be weaker, resulting in a 'spring back' effect. It becomes crucial to account for this spring back when calculating the bending angle or punch depth.

Air bending is particularly suitable for scenarios involving thin sheets requiring diverse bending angles, where strict accuracy requirements for bend angles are not paramount.

Bottom Bending

In contrast to air bending, bottom bending exerts significantly greater force through the punch, completely molding the sheet onto the cavity surface without leaving any air gap. The force applied in bottom bending is 3-5 times higher than that in air bending, effectively eliminating the spring back effect. This technique is well-suited for bending thicker sheets (above 2 mm) with more stringent requirements for bending angles.

In bottom bending, the bending angle is determined by the angle of the die. Consequently, a distinct die is necessary for each specific bending angle. This characteristic makes bottom bending particularly advantageous in situations where only a single type of bend is needed, such as in the production of hinges or clips.

Need further assistance? 

Let us help! Talk to our expert sales team for more information on brake presses, tooling options, and picking the perfect machine. Give us a call or submit a contact form here to talk to our staff.