Tube bending tools engineering


Tube bending for lot of people seems to be a very easy job. That is why there are a lot of discussions when the case is to sell the modern and high technology tube bending machine. Manufacturer tries to explain what all the options for, what are the problems and why finally the machine cost so high! Sure thing all the things are clear enough for the people in really productivity industries like automotive. But when the story is for other applications…

Tube bending tools could be quite expensive as well. Mainly there are two main principles – main sizes and complexity of development and production. Any even simple tools for big diameters for oil and gas lines, shipbuilding etc. when the diameters are nearly hundred and more cost lot of money. For small diameters the cost could be for complicated tools with the special surfaces, short clamping parts for tight block of the tube, multi-stack tools with several radiuses on one tool to work with different planes…

Moreover the responsibility is high! There are no unification and standardization; tooling is only for the specific machine and specific job to do. Even sizes of the tools are different – all manufacturers have their own connections to tie the customer with the future tooling supplies. And for bending tools there is only one result – to bend the tube with proper requirements. Yes, a lot of depends on the machine and the operator skills for setup but tool is main and general part you can’t ignore.

Complicated tube bending tools are really look impressive. And the jobs with them are the really wonderful view to explain for potential customers all the possibilities and functions. A sure thing, a lot of depends of the costs but if you run the machine for half of million USD with the thousands of parts for daily production you can’t ignore the quality tools. Otherwise why do you purchase the machine?

Profile bending machine


When you should need at and can replace standard tube bending? Profile bending machine or section bender or “3 rolls tube bending machine” is the machine to use principle of driven rollers and the force of the middle roller to form the bend. But we will not talk about the technology so we will talk when you can use it…

Main restrictions of the possibilities are small radius bends. So to form radius with 3 or better 5 diameters of tube is not the problem but with tight radiuses – forget about this type of the machinery. So it is not the machine for industrial pipelines or connections but the good machine for design and architecture, spirals and some outdoor products, greenhouses tubes.

The investments could be very low for small machinery. Machines are very simple, with mass market and a lot of manufacturers it the world so if you do not have really special product (for example to make the cabin profile with different radiuses in one cycle) you can easily find the machine with your budget and necessities. Do not ask a lot of this type of the machinery but know that real CNC versions could be very interesting to change radius. Some German and Swiss companies offer the precise versions – with more hard price but to make more precise parts for the field, for example for boat railing where pair of tubes needs to be really mirrored without any difference.

Every time note that profile bending machines has the specialization for the profiles. It is very complicated to deal with bar or beam with tube bending machine so profile bender is only choice for this kind of applications. The machine possibilities are calculated for the bending of solids and not the hollow pieces.

Tube bending fitness


Because lot of people are interested what could be created with tube bending in general life without opening covers of aircraft engine we will continue… What industry is massive, mainly tube bended and rich enough to invest with the most modern tube bending machines? For sure it will be gym and fitness equipment manufacturing. Just imagine how many cities, how many gyms, how many units inside…

Some statistic figures: in US there are more than 34 thousand fitness centers, the quantity for worldwide: around 153 thousand. The market revenue for gym and exercise equipment is around $ 2 billion USD. Under some researches gym and fitness equipment market worldwide is expected to reach $11.9 billion by 2020. And the great percentages of materials in equipment unit are the bended tubes. So you can imagine how huge this production branch!

Market leaders work with real high production so the tube parts are not the subject for manual bending technologies. Usually companies purchase electric multi-axis CNC automatic benders to make the parts with the highest speed with the best repeatability and the quality. In general, tube geometries are not very complicated but requirements for non-availability of surface deformation, scratches or tube ovality could be very high.

Manufacturing of gym and fitness equipment doesn’t require any serious special developments and complete changes of the technology. As the engineering stage everything is very near to the ideal today so the next supplier of the machinery will be the company who will offer high speed full-electric for the best price. For sure the industry is adapted for automatization solutions but this will be outside of the machine.

Tube bending parts as basic architecture product


Today designed applications and special orders are very popular in the world. Many agencies in Germany and Switzerland use really expensive and high-end technology tube bending machinery for architecture and designed tubular parts for outdoor and indoor use. With the new fashion for modern “metal and glass” buildings the tubes could be also the main part for the elegant constructions. Could be even not the part but the really monuments as in some US cities. Tubing is very popular not only for different handrails but for street furniture too. Unique pieces of stainless steel made by imagination of project engineers are the pretty part of the modern cities. Tent-like solid constructions, all circular stairs railings, roof covers – you just need to look around the best modern constructions in your city and study if they have tubes inside.

To move out from the classic street we can view the custom made boat railings. Expensive boats are every time the special and individual work so the railings (and as you can consider there are a lot on the boat) are every time different too.

What is the most interesting moment in tube bending? The classical 3D tube bending offers the movement of tube with any direction with some limitations and restrictions. But anyway it is the subject for any fantasy and idea to realize, just necessary to have the necessary tube bending tools according to your application. Usually companies involved in architecture use classic draw tube benders together with section benders (3 roller machines) because with them you do not have the necessity for tools of every radius of tube.

Tube bending part is much simpler to achieve than the classic metal construction parts. This is the reason why architecture moved to tube bending. To bend profiles more complicated for free-form solutions, other structures like bars – more complicated for machinery and realization.

The photo is the sculpture “Brain” by Paolo Matroian


Furniture – global boost for tube bending industry


If you will forget about different tube line applications what could be the big use of tube bending? Sure it is furniture. There is no other massive industry which consumes so much bended tubes for different products. You can just look around and for sure you will find something also near you. Nobody will tell you how many millions of bended tubes are produced every year for example, for iron boards. Moreover we can talk not only about mass market products. It is known that there a lot of design chairs are produced with unique styles and with the use of modern and very expensive tube bending machines.

Yes, in generally bending of tubes for furniture is very simple. In lot of cases it is enough manual or simple semi-automatic machines so the investment for start could be very low. But from other hand furniture is very profitable business for high production and where you mean high production you should consider very high speed production cycle and it is the reason why even for simple applications lot of companies use serious modern machinery. Moreover to save the time and eliminate the human factor loading and unloading operations are performed by robot or other system for automation.

Why we are talking about so serious boost. Just necessary to imagine that in the world there are so many furniture suppliers so if it is very hard to enter the automotive supplier chain it could be much easy to produce parts for furniture. Moreover high production means the development of serious automation for the maximum reduction of fabrication time. And the last thing could be that the start could be done with simple machinery so entry level is not so expensive compare to other markets.

As we said before usually products are simple. But it is very attractive to see the special designs with the bending of full chair body with one tube and full automatic cycle. 3D tube bending solutions in general have no limits so with the powerful machine you can develop a lot of various, stylish and impressive products.

Special tube bending tools


Besides all different principles of tube bending the execution of special tools is real “state of art”. What is the necessity? Some tubes, in particular in automotive industry require not the standard principle of tube bending performed by tube bending machine as “bend – straight part in min. length as straight part of the clamps – second bend…” Some tubes have no any straight part so the area of this bending is named as “bend in bend”. It is quite impossible to perform this technology with standard tube bending tools and mandrel tube bending machine – there are no possibility of clamping! The solution could be only to manufacture the special tools for the required part where the clamps dublicate the first bend in the groove to make the second one. Tooling to make these parts is really expensive so this is the big question for investments but there is no other way to do the part without the special tools.