What is a Hydraulic Press Brake?

Hydraulic press brakes are essential tools in sheet metal fabrication industries. Not only is it secure and user-friendly, but its convenience also makes it perfect for any shop.

When selecting a press brake, make sure to choose one capable of bending the material you require. Additionally, select an ideal model with suitable tonnage and bending length for your application.

What is a Hydraulic Brake?

A hydraulic press brake is a machine tool used to bend sheet metal. This device consists of a die set and punch that precisely bends the metal at an angle.

The bending force for this ram is provided by synchronized hydraulic cylinders on the C-frame that move it. This gives the ram complete control while in motion and even allows it to reverse a stroke at any time.

This type of press brake is ideal for processing large volumes and heavy tons of workpieces. Furthermore, it offers stability and dependability during bending operations.

CNC hydraulic press brakes offer multiple shapes and can process various metal types. Not only do they reduce job setup time, but they also drastically increase productivity levels.

The Die

The die is an essential element of a press brake, responsible for bent sheet metal and producing desired profiles.

Utilizing the correct tooling can enhance bending efficiency, reduce costs, prevent profile deformation and safeguard press brake operators from injury. Additionally, it has an effect on the bending angle, internal radius, minimum flange length and aesthetic appeal of a workpiece.

A suitable die should be constructed from material matching the tensile strength of the metal sheet it will bend. Different press brake dies exist for different tensile strengths and thicknesses.

The V-die is the most commonly used die type. It features a V-shaped opening that permits metal plates to be bent according to engineer's specifications. This shape evenly distributes force across the plate surface, preventing cracks in the sheet metal.

The Ram

The ram is the part of a press brake that compresses sheet metal and bends it into its desired shape. It works like a plunger, activated when hydraulic fluid flows through pipes and into an enlarged cylinder.

Hydraulic rams come in various sizes and capacities to handle large loads. Not only are they accurate and dependable, but they use minimal energy as well.

Mechanical rams require more maintenance and are costlier than hydraulic rams, but they offer greater customization and precision. Operators can input data such as bending angle and plate thickness into a controller which then directs the machine's action.

A distributed drive system evenly distributes the weight across a ram rather than placing it all in one spot, which could cause deflection at its center. Wedges and hydraulic cylinders help compensate for this deflection and ensure the ram is crowned properly.

The Upper Table

The upper table is another essential component of a hydraulic press brake. It consists of a welded steel plate that moves along a gibbed way system with either mechanical stops for fine adjustment or more accurate electronic scale feedback methods that provide precise positioning and angles of bend.

In the past, hydraulic press brakes applied their bending force through two rams on each side of the bending bed. Unfortunately, this can result in an uneven distribution of force across the bending area.

This can lead to a phenomenon known as "canoeing" of the internal bend angle. This occurs when pressure from hydraulic cylinders on either side of the bed concentrates near their respective centers, then diminishes toward their outer edges.

To combat this, press brakes are often designed with either a fixed crowned table or adjustable table that can be quickly adjusted to create the desired curve. This helps minimize set up time and maximize production rate while producing high quality parts.