Requirements in tube bending

The three principal requirements in tube bending are simply: machine, operator and tooling.

All three factors must be especially good to work with thin wall tubing on tight radii. Too many facilities still depend on the operators genius to compensate for near useless tooling. Poor tooling results in longer set-up time, scrapping of expensive tubing, poorly bent tubes and fail to produce an acceptable pipe bender. Highly competitive custom tube bending companies realize cheap and inferior tooling is the most expensive they can buy. Interlock tooling represents the ultimate in tube bending tooling. Complete interlock tooling, although developed and successful for numerical control tube benders, has proven advantageous for conventional machines. Each tool of the matching set is laterally locked in alignment. The clamp die is keyed and locked to the bend die, the wiper die located and locked to the pressure die, and the pressure die in turn is locked in alignment to the bend die.

Field reports have confirmed several advantages of interlock tooling. The clamp die, with all the hydraulic pressure available to it, will not crush or even mark the tube, thereby providing vastly improved gripping properties. Bend die and pressure die marks on the top and bottom of the tube are completely eliminated. In 23 instances tested, set up averaged one-third the time allotted for conventional tooling. A 32% reduction of scrap was recorded over previous runs using conventional tooling.

The five pieces of tooling (bend die, pressure die, wiper die, mandrel and clamp die) must all be close-tolerance excellent tooling. The bend die should have a maximum run out at the bottom of the bend groove of not more than . To help prevent tooling marks on the top and bottom of the tube bending machines, the bend groove should be deeper than half the tube diameter. The bend groove should be dead round and the diameter should measure 10% timeís wall thickness over tube diameter. The clamping area, unless cleated or with other provision such as flaring, beading, etc., should be three to six times tube diameter with a sandblasted or rough finish. The diameter of a clamp area should not be undersize more than 10% of wall thickness. Grip or pinch clearance should be held to a minimum. To permit the bend die to be used on right and left hand machines, the counter bore and keyway often are machined on both sides of the die. Centerline height must be maintained for both sides.

BENDING WITH BALL MANDREL AND WIPER DIE

When the radius of the bend is smaller and/or the wall is thinner, it becomes necessary to use a

ball mandrel and wiper die. The wiper die is used to prevent wrinkles. The ball mandrel performs like a plug mandrel. The balls are used to keep the tube from collapsing after it leaves the mandrel shank.

Bending issues are enlarged when making tight bends or with thin wall tubing. It becomes more difficult to retain the material during compression.

The pressure is so intense the material is squeezed back past tangent and buckles. This area must be supported so that the material will compress rather than buckle; this is the prime purpose of the wiper die. Note, the wiper die cannot flatten wrinkles after they are formed; it can only prevent them.

Bending thin wall tubing - requirements for the bending of thin wall tubing with tight radius bends of centerline radius equaling the tube outside diameter have become more common in recent years.

To increase the problem, new alloys have been developed that are extremely difficult to bend. The proper bending machine, good tooling, and a trained operator can make all the difference.

To facilitate this type of tube bending, the material to be bent should receive special consideration. To help maintain the consistency of the tubing dimensions and characteristics, the entire material required for a given job should be acquired from one supplier, preferably even from the same lot or heat number. Premium-priced close-tolerance tubing should be considered. It often saves many more times its added cost. It may be necessary on occasion to size certain tubing before bending.

There are many pipe bending machines but only a few are capable of thin wall, 1 x D bending.

Even those machines best suited for this special bending must be in excellent condition and of a size large enough to assure rigidity. The machine must be capable of retracting and advancing the mandrel with the clamp and pressure dies closed. A hydraulically actuated pressure die is desirable. One feature of this system is that it provides identical pressure on the tube regardless of wall variation.

A pressure die boost counteracts the drag of the pressure die, mandrel and wiper die. It pushes the tube into the bending area, preventing excessive wall thin out.

Without a pressure die boost, the thinning that normally can be expected is about three quarters of the elongation of the outer wall. Companies specialized in steel bending automation for a broad array of fabricated products, includes CNC tube benders, tube measuring equipment and complete cellular integrated systems.

BENDING TUBE

A bend die, clamp die, and pressure die are the minimum essentials for tube bending. The bend die helps to prevent the tube from flattening and forms a given radius of bend.

The clamp die holds the tube in position while bending. The pressure die forces the tube into the bend die.

Springback is excessive when a mandrel is not used. This should be considered when selecting a bend die. Springback is the term used to describe the tendency of metal that has been formed to return to its original shape. Springback will cause the tube to unbend from two to ten degrees depending on the radius of bend, and may increase the bend radius of the tube. The smaller the radiuses of bend the smaller the springback.

The tube may kink or buckle, this may be due to hard material which will not compress on the inside radius of the bend. The material, not being able to compress, pushes in toward the centerline of the tube. This condition can be corrected (provided the tube is not too hard) by proper set up of the tooling. A plug mandrel is indicated if the tube buckles and is still within the wall factor and the diameter of the bend.

The purpose of a plug mandrel is to prevent the tube from flattening and to bend without wrinkles or kinks. The mandrel is held in a fixed position while the tube is pulled over it. The tube stretching process is localized on the outer radius of the bend and the material is work hardened to retain its shape and not flatten. The material stretching is done on the forward tip of the mandrel. This force, acting on the mandrel tip, supports the inner radius of the bend, holding it firmly into the bend die groove. CNC bender is used on CNC benders from 0.25" inch to 6" inch tube bending machines.

The pressure die should be adjusted for a light pressure against the tube. The purpose of the pressure die is to keep the tube against the bend die through the duration of bending. The pressure die also keeps the mandrel from bending and maintains a straight tube between tangent points of bends (the portion of ubing left on the mandrel after steel bending). The location of the mandrel affects the amount of springback. The mandrel in a forward position (toward tangent) will stretch the material on the outside of the bend more than is necessary. This increases the length of material on the outside beyond that which is required to make a bend. When the bent tube is removed from the bend die, it will conform to the die and there will be little or no springback.

TUBING BENDERS

Tubing benders come in many sizes, for use in everything from heavy construction to auto building to home landscaping. They range from a 16-ton hydraulic pipe bender to a handheld bender for small-gauge copper and aluminum tubing. All of them, however, use one of four basic methods. Ram bending is the cheapest and easiest method. Tube benders are restrained at two ends and a ram deforms the pipe in the middle. This is suitable for light gauge tubing only. Rotary draw bending is the most commonly used method, and maintains the diameter of the pipe without deformation. In this method, the tube is drawn through a stationary counter-bending die onto a forming die of a specified radius. These tube bending machines are used in the formation of exhaust pipes, process pipes, and any aluminum or stainless steel application where interior deformation can't be tolerated. Bending is similar to rotary draw bending, except that the interior of the tube is supported by a flexible mandrel. The mandrel bends with the tube, ensuring that the interior diameter is not deformed. Ring roll bender is used for bending pipes and tubes with a large diameter. There are three rollers, two on the bottom and one on the top. As the pipe is rolled through, the top roller exerts a downward pressure, bending the pipe. The pressure of the top roller can be adjusted manually or hydraulically, and either two or all three rollers can be powered. This method is used to make drum barrels, awnings, and other circular shapes.

For a tube bending, two things happen to metal. The outside wall is reduced in thickness due to the stretching of the material and the inside wall becomes thicker due to the compressing of the material. The material actually is formed approximately about the centerline of the tube. The material that forms the outside of the bend has further to travel and therefore is stretched; the inside of the bend has less distance to travel and is compressed.

When the ratio of the tube diameter to wall thickness is small enough, the tube can be bent on a relatively small radius. Excessive flattening or wrinkling of the bend should not occur. The outside and inside of the bend tend to pull towards the centerline of the tube. Two factors that help prevent this from happening are a grooved bend die, which supports the tube along the centerline and the natural strength of the tube.

Tube and pipe rollers

The tube and pipe roller or roll bender machines consists of manual or electronic driven single pinch ring roller machines (noting some have a hydraulic top roll with DRO) and hydraulic driven double pinch models with two hydraulic bottom rolls. The company has a very diverse line of angle roll bender machines to bend tube, pipe, angle iron, solids, squares, and much more.

The manual pipe bender machines consists of two manually driven ring roll benders for bending up to 1-1/4" tubing. These are great tube roller machines for the hobbyist or metal artist. The company also has several ring roller machines that are electronically driven with variable speed inverter drives. These ring roller machines have greater capacities and are easier to operate with two driven bottom rolls. These powered tube roller machines can bend vertically or horizontally for larger section angle bends. All versions in this category have manually adjusted top rolls and are considered single pinch style machines.

The single pinch angle rolls bender line with hydraulic down feed of the top roll has digital positioning readouts for repeatability. The tube benders in this category have three driven rolls for extra power. These roll bender machines are perfect for production fabrication settings where the fabricator is making hay hoops, spiral stair cases, and much more.

Finally the company offers two versions of double pinch angle rolls, hydraulically driven roll benders with hydraulic positioning of the two bottom rolls that are coupled to two separate digital readouts. These angle roll machines have three hydraulically driven rolls. We also have two angle bending machines that have hydraulically driven rolls, hydraulically positioning bottom roll, as well as hydraulically driven lateral guide rolls. These ring roller machines are for bigger section bending projects or for more structural applications. A double pinch bender allows the operator to pre-bend and post-bend the material saving the fabricator time and money. These roll bender machines are easy to use, cost effective, and built for decades of service.

Features:

· Bending capacity to 6″

· Bend any angle to 180° with independent material spring back compensation for each bend

· Bend to CLR as small as 2.5D

· Ideal for producing consistent quality bends in large diameter pipe, tube, squares, rectangular, solids and other profiles

· PLC touch screen control offers easy access to operating modes, programming, system diagnostics and multiple language capability

· Patented quick-change tooling system with multiple radii available

· Remote foot pedal for hands free operation

TOLEXPO – 15-18 November 2011

A partnership with the Midest and Maintenance Expo to create:

· a communication synergy promoting the sector

· a technological showcase bringing together subcontractors' and equipment manufacturers' know-how

The 4^th edition of TOLEXPO, the international show for sheet metal, coil, tube and section

equipment, organized by DBR Event will be held at Paris-Nord Villepinte Exhibition Centre from 15 to

18 November this year. As the economic recovery begins, Tolexpo confirms its position as an

industrial event firmly dedicated to the sector and confirms the success it has achieved, with both

exhibitors and visitors, since its creation in 2005.

6 months before the show opens, Tolexpo already has more than 200 exhibitors, among them both French leaders in the sector and the majority of foreign manufacturers, between them there is also Tauringroup which is a world leader in tube and pipe bending machines.

Almost 11,000 targeted visitors looking for new equipment will discover the products and technical innovations offered by suppliers at the show.

At Tolexpo, visitors will find solutions to all their needs, whether they are looking to renew or modernize their equipment, begin using new technology, improve their productivity, bring their businesses into line with standards and regulations, etc.

For the first time this year, in partnership with the Tolexpo show, Tôlerie magazine is organizing a

competition for students in the various areas which involve sheet metal working.

A Challenge which will bring students together: the Tol&Design Challenge has been created to put the spotlight on the expertise of young people who have chosen the various subjects which involve sheet metal working, and aims to promote these subjects and the production chain itself, by bringing students together to work on an industrial project.

It is also an opportunity for the students to present their expertise to industry professionals by

creating finished products - in this case a chair - using precise specifications.

An initial analysis of the applications shows that students are particularly committed to this project

which is closely connected with the world of work. Teamwork, together with the students' fabulous

motivation, gives them the opportunity to bring their apprenticeships to fruition by carrying a

project through from A to Z.

The organizers of Tolexpo, Midest, the global sub-contracting show and Maintenance Expo, the

maintenance solutions show, are continuing to work together in order to create communication

synergies and boost their industry sectors.

The major objective is to create a technological showcase which will bring the expertise of subcontractors together with that of production equipment manufacturers.

Further insights:

http://www.tolexpo.com

BATIMAT – 7-12 November 2011

BATIMAT is the essential meeting place for the French and international construction industry. Playing a central role in tackling the energy challenges facing buildings, BATIMAT is the place where the technical solutions emerge that will characterize sustainable construction and renovation projects. BATIMAT is a real springboard for manufacturers who want to launch their technological innovations and massively speeds up the rate at which new ideas and products are adopted, one of these is Tauringroup that offers top quality angle rolls and bending machine.

As well as its professional role, BATIMAT is also the place where the entire profession gets together in a pleasant atmosphere.

BATIMAT 2011 will serve as one of the shop windows for these developments by featuring innovations and model projects by architects and hosting conferences and events. It will enable professionals to find out about the products that will take centre stage tomorrow.

BATIMAT will also speed up progress. For example, another major theme of the 2011 show will be accessibility for persons with restricted mobility. On 1st January 2015, existing buildings that are open to the public and residential buildings will have to comply with the requirements of the new law on accessibility. BATIMAT will feature this theme through conferences, demonstration areas and round tables.

The 2011 show will be right at the heart of developments in the energy efficiency of buildings.

One of the objectives of the Grenelle de l’Environnement (the French environment initiative) is to spread the concept of the “Low Consumption Building” from 2012 onwards through the adoption of a new set of thermal regulations, the “RT2012”, which will replace the current 2005 thermal regulations.

These new regulations will come into force in the second half of 2011, will result in a major development in technical and architectural approaches on buildings. This development will bring an increase of innovative products and an increasing demand for training from professionals.

Editions des Halles presents a modular wood-home prototype. Located at the center of this 6-day event, this is the opportunity to follow-up on the wood industry's desire to answer the environmental preoccupations of construction.

With the support of France Bois Forêt (French Wood Promotion Fund)

The aim of the Zero Carbon Habitat is to prove that, today, one can build and live all while drastically reducing their carbon footprint.

In these times of urban densification and the desire to optimize real-estate resources, the Zero Carbon Habitat delivers simultaneously an economical and environmental answer, two dimensions that are often hard to conciliate.

Further insights:

http://www.batimat.com

BATIMAT – 7-12 November 2011

BATIMAT is the essential meeting place for the French and international construction industry. Playing a central role in tackling the energy challenges facing buildings, BATIMAT is the place where the technical solutions emerge that will characterize sustainable construction and renovation projects. BATIMAT is a real springboard for manufacturers who want to launch their technological innovations and massively speeds up the rate at which new ideas and products are adopted, one of these is Tauringroup that offers top quality angle rolls and bending machine.

As well as its professional role, BATIMAT is also the place where the entire profession gets together in a pleasant atmosphere.

BATIMAT 2011 will serve as one of the shop windows for these developments by featuring innovations and model projects by architects and hosting conferences and events. It will enable professionals to find out about the products that will take centre stage tomorrow.

BATIMAT will also speed up progress. For example, another major theme of the 2011 show will be accessibility for persons with restricted mobility. On 1st January 2015, existing buildings that are open to the public and residential buildings will have to comply with the requirements of the new law on accessibility. BATIMAT will feature this theme through conferences, demonstration areas and round tables.

The 2011 show will be right at the heart of developments in the energy efficiency of buildings.

One of the objectives of the Grenelle de l’Environnement (the French environment initiative) is to spread the concept of the “Low Consumption Building” from 2012 onwards through the adoption of a new set of thermal regulations, the “RT2012”, which will replace the current 2005 thermal regulations.

These new regulations will come into force in the second half of 2011, will result in a major development in technical and architectural approaches on buildings. This development will bring an increase of innovative products and an increasing demand for training from professionals.

Editions des Halles presents a modular wood-home prototype. Located at the center of this 6-day event, this is the opportunity to follow-up on the wood industry's desire to answer the environmental preoccupations of construction.

With the support of France Bois Forêt (French Wood Promotion Fund)

The aim of the Zero Carbon Habitat is to prove that, today, one can build and live all while drastically reducing their carbon footprint.

In these times of urban densification and the desire to optimize real-estate resources, the Zero Carbon Habitat delivers simultaneously an economical and environmental answer, two dimensions that are often hard to conciliate.

Further insights:

http://www.batimat.com

MADE EXPO – 5-8 October 2001 industry machinery

Made Expo is an international architecture and building trade show.

The third edition closes on an high note with 242,152 visitors, an increase of 21%, of whom 23,810 were foreigners (+24%).

This international event dedicated to the world of planning and building confirms its role as leader in the sector, a must-visit business appointment on the trade fair calendar and at the same time a chance for collation by operators and relaunch by the industry sector, a showcase for qualified goods with a high innovation content.

“We are completely satisfied by the result achieved”, state the organizers, “not only in terms of figures, but also and above all for the positive mood felt in the halls during the event. Over 1,700 companies took part, 254 of them from abroad, in more than 90,000 net m² of exhibition space, showing great tenacity and a desire to react to this difficult economic period. MADE expo once again proved to be an effective tool for companies, which found important business opportunities, services and in-depth analysis at the show. There was unanimous positive feedback from visitors regarding the high machine innovation and research content presented both on stands and in the cultural and technical initiatives”.

Over 180 meetings and events were on the agenda during the four days, highlighting the most relevant issues for contemporary building.

“Thanks to an innovative format that combines services and products with technology and culture”, continue the organizers, “MADE expo does not stop when the fair closes but heads towards the fourth edition, scheduled from 5 to 8 October 2011. During this period, MADE expo will continue to work, through international appointments and initiatives that will mark the months leading up to the next show. The priority for MADE expo is to support companies along the road leading to the great challenge that is EXPO 2015, which has chosen this trade fair as a benchmark for the construction system, a sector playing a lead role in development of the planet from a new perspective of sustainability for the environment and man”.

The new edition, with these conditions, will be a success. An event that was created to meet the needs of the international market, which has increasingly felt the demand of a larger trade show that allows companies to expand their commercial horizons, to make connections with international customers and search for new sales channels.

MADE expo, the landmark international event for the world of architecture and design, has responded to these needs by developing plans for a new exhibition specifically dedicated to the design world, contracting and for the interior decoration.

A showcase filled with proposals, suggestions and ideas which becomes, for the visitors of MADE expo, an opportunity to update on the latest innovations and trends. Among the last Tauringroup successes the company will present advanced technology in CNC bender.

Further insights:

http://www.madeexpo.it/en/

EMO HANNOVER - 19 September 2011

On 19 September 2011 the EMO Hannover, the world's premier trade fair for the metal working technology will be opening its gates. For six days the city of Hannover will be the center of attraction for production specialists from throughout the world, the meeting point for the entire international sector.

Round about 2 000 companies from 40 countries will be showcasing the entire spectrum of products and services almost for the metalworking technology - spotlighting their performance capabilities and innovative vigour for the highly qualified experts. This year's EMO Hannover is presenting its products and events under the motto "More than machine tools".

Whether as an exhibitor or a trade visitor, a journalist, technically oriented youth or a representative of the political and academic communities, on our website you will find all the important information you need on EMO Hannover 2011.

Display Categories:

· Machine tools for cutting, splitting and milling

· Sheet metal, wire and tube working machines, metal forming machine tools

· Machine tools for thermal, electro-chemical and other processes

· Surface finishing technology, thin-film processes

· Software for entire manufacturing technology area

· Control systems

· Components for flexible automation

· CAD/CAM

· CNC bending machines

· Quality management systems

· Robotics and automation

· Material flow and storage technology

· Industrial electronics, sensor and diagnostic technology

· Precision tools, diamond tools, measuring tools

· Metal forming machine tools

· Tube benders

· Machines and systems for tool and mould construction, rapid prototyping, model construction

· Instrumentation and control technology

· Coolants, lubricants

· Welding, cutting, hardening, heating

· Mechanical, hydraulic, electrical and electronic accessories for manufacturing technology

At EMO Hannover 2011 we again will offer trade visitors a series of events, supplying them with additional information. Also Tauringroup, leader in metal bending machines, will show its new products in this exhibition.

One of the theme of the conferences is new manufacturing production technologies for the aerospace sector. The aerospace industry has become a significant technological and economic motor for the manufacturing location Germany over the past years. High market requirements with regard to minimal fuel consumption, high cargo capacities and extended range of airplanes lead to a growing demand for light and high-strength structures at the same time. For the first time, the Institute of Production Engineering and Machine Tools (IFW) at Leibniz Hannover University will be hosting its prestigious conference entitled "New Production Technologies in the Aerospace Industry" at the EMO Hannover. The event is co-organised by the nationwide Machining Innovations Network (MIN). EMO visitors from the aerospace industry will be offered a top-class forum for acquiring new information and exchanging news and views about the status of research work on an international level.

Further insights:

http://www.emo-hannover.de/homepage_e

BENDING STEEL

The equipment used for bending is the most advanced of its kind in the world. Tooling has been developed over many years to virtually eliminate distortion of the section when bending. If there is a critical application where section integrity is important the company should be your choice of curved steel supplier.

The company is technologically advanced in all aspects from customer communication and work administration to computer controlled bending and cutting.

Capacity in each of the specialist services covers the whole range from very small sections and thin plate up to huge sections 1000 mm in size and plates up to 100 mm thick. Production system is modern and efficient. Small orders for two rings can run alongside large multi million-pound call off orders.

The company has mastered the craft of bending steel. It can produce virtually any metal component that needs to bend or curve and has an impeccable reputation in the steel bending and fabrication industry, for producing difficult and unusual parts that require bent steel, for tube bending or pipe bending machines.

This is an industry leader in structural steel bending, steel rolling and steel forming. The company works with all forms of structural steel (angle, wide flange and I-beams, channels, rectangular and square tube, and bars), as well as virtually any other ferrous and non-ferrous metals. Metal bending machine and steel forming expertise allow to produce state-of the art canopies and roof trusses, bridges, entry-ways and store fronts, stadiums and parking garages.

In addition to structural steel bending, our tube bending machines and pipe bending capabilities range from the very small to the very large. Pipe bends and metal tube bends can be found in the form of modern art sculptures, pedestrian bridges, exercise equipment, furniture, playground equipment, bike racks and bollards, and much more.

This is an industry leader in spiral, circular and helical bending, that has the ability to produce steel and metal spiral stringers and staircases. Other ornamental applications include custom handrails, decorative gates and fences, and unique signage.

Other bent steel applications include parts supplied to light and heavy industrial customers. Products include boiler tubes, heat exchangers, coils, pipe sections and tanks, pipe spools, hydraulic lines, solar panels, chip lines and much more. In addition, the company serves the marine, locomotive, aviation, automobile, agricultural, and medical and dental industries with unique, high quality parts that require metal rolling or bent steel.

To the most common forms of structural steel, the company also bends other miscellaneous material types, like architectural rail cap, railroad iron, rounds bars, square bars, etc.