Tube benders for large diameter tubes and bars are systems capable of applying the considerable thrust forces and bending torque required to bend large pipes and are also able to optimally control the force exerted on the tube and the deformation of the material through the interpolated movement of the core, slide and clamping.
As the diameter of the tube to be bent increases, the technological complexity of the machine also increases: the support structure of the equipment becomes more robust, and the tube handling systems must be carefully designed to adequately manage the deformation of the material.
For this reason, when bending large diameter tubes and for thick or solid bars, tube benders with only right or left bending directions may be preferred, where the bending torque is strong enough to bend tubes even up to 150 mm in diameter.
This type of system is ideal for hydraulic and structural applications, in the frames of industrial vehicles and agricultural machinery, in the naval and energy sectors and sometimes, they are also used in aerospace when the materials have very high rigidity and strength, despite being thin.
Usually, when producing components with large-diameter tubes, the capability of bending in only one direction – either right or left – is completely sufficient because the resulting parts are typically short and have a simple shape.
However, there are some applications that require bending tubes with larger diameters – up to 63 mm – smaller tubes with high-strength materials or those with particularly complex shapes, for which it is necessary to use an in process right- and left-hand tube bender.
A classic example is torsion bars, which must be made as a single part for proper mechanical resistance and safety, and within a single system to guarantee precision and repeatability.
When manufacturing torsion bars, the tubes may have significant thickness even with small diameters and the material may have a high yield strength. Therefore, the tubes will require a much higher bending force to process.
Contractors are also core users of right and left CNC tube benders for large diameters. In fact, all those who work on behalf of third parties can take advantage of the wide range of diameters that these tube benders can support, to more efficiently satisfy the needs of different sectors.
For example, a tube bender with two bending directions, capable of mounting up to 8 bending tool stacks, allows fabricators to work on different diameters without having to change tools, only the clamp and mandrel, thus being considerably easier to use and efficient.
There are also other applications where the ability to bend right- and left-hand large diameter tubes offers a significant advantage, as it makes the production process more efficient and simpler. For example, in sectors such as industrial plants, water treatment, pharmaceutical and petrochemical, the production of complex shaped pipes in a single piece eliminates welds, which are generally the weakest points of the pipeline, hinder the flow of fluids and are easily subject to oxidation.
In-process right- and left-hand tube benders must have specific technical characteristics for producing complex tubular components of large diameter, thickness or high-strength material. This distinguishes them from other right- and left-hand in-process tube benders, commonly used for smaller diameters.
Familiarizing yourself with these differentiating factors will help you understand how the machines work and be an integral component of evaluating your next bender purchase. Here are some of the features that a right- and left-hand tube bender must have for large diameter and thick tubes or material of high resistance.
When bending torque increases, a compact bending head is imperative for in-process right- and left-hand tube benders. This is critical for part geometric feasibility.
The perfect balance of these elements can significantly expand the number of possible applications and is a main deciding factor for your machine purchase. The process of arriving at this balance is arduous and can only be achieved by extremely experienced manufacturers.
To ensure optimal versatility and usability as well as increase the range of feasible applications, independently bending head locks are critical.
With these independent head locks, it is possible to mount equipment with very different Center Line Radii (CLR) between the right and left side and greatly increase the number of parts that can be produced in a single work cycle.
High thrust force becomes essential in all cases that involve variable radius tube bending. When performing variable radius bends, the thrust force of the carriage drives the process, and more power is required as the diameter of the tube increases. Therefore, the ability of the machine to carefully adjust the thrust force over the course of the bend is critical.
The bending of torsion bars and high-strength materials is taxing to the system. Therefore, the frame structure and the head kinematics must be appropriately designed to support the high-dynamic loads involved and ensure the reliability of the system over time.
The ability to quickly change production is one of the fundamental requirements for a modern automatic tube bender. This feature is especially essential for subcontractors, as it allows them to adapt with great versatility to the different industrial sectors in which they operate.
This type of system is driven by tube bender programming software that simplifies production changes by estimating the elongation and springback of the tube during bends and adjusting the part program parameters accordingly.
BLM GROUP tube benders use VPGNext, a programming software that precisely calculates the tube's response to bends and grants the first right part to be obtained at every production change based on pre-programmed material data and the individual machine’s specifications.
The new E-TURN63 tube bender from BLM GROUP offers all these features. The careful design of every detail, the new generation VGPNext software and the wide versatility of use combined with the powerful working capacity, make it the perfect system for right- and left-hand in-process bending for tubes of large diameter, thickness and high rigidity.