Chapter 1. What is a pipe bending machine?
The pipe bending machine is a kind of equipment for cold bending processing of metal pipes and profiles. The bending process is a stretching process. During the bending process, no coolant is required. In some cases, drawing oil is required to reduce the resistance between the pipes and the pipe bending tools, which could improve the quality of bends, and extend the service life of the pipe bending dies.
Chapter 2. What exact materials can pipe bending machine bend？
The pipe bending machine can bend stainless steel, iron, carbon steel, copper, aluminum, and titanium, and other metals. Usually, the default bending material is metal, not other materials such as plastic. Because the metal material has a certain degree of ductility and small elastic deformation, and the material itself has a certain degree of support for the curved section structure, through the work of pipe bending tools, the quality of the bends can be guaranteed, no collapse on the outer curve and no wrinkles inside.
Chapter 3. What are the applications of tube bending machines？
Pipe bending machines are indispensable for many industries, such as furniture, construction, lighting, various types of transportation, and so on.
Let’s take a look at which industries are using tube bending machines.
1. Automobiles: Pipe bending machines are seriously needed in the automotive industry. At present, the most extensive pipe bending is mainly used for auto parts. Many pipe bending processes such as exhaust pipes and radiator pipes are more complicated. Most of the pipe bending machines used are CNC pipe bending machines. Exhaust pipes, fuel brake pipes, air conditioning refrigeration pipes, mufflers, seat frames, headrests, hood struts, door lock levers, etc. all need a pipe bending machine to bend.
2. Motorcycles: handlebars, bumpers, chassis, etc.;
5. Bus, passenger car
6. Truck: fuel line, engine pipe
7. Agricultural equipment: such as harvesters
8. Food processing equipment, such as milk sterilization equipment pipeline
9. Iron, steel, aluminum furniture: office desks and chairs, student desks and chairs, beds, sofas, mirror frames, ironing boards, aluminum ladders, etc.
10. Boiler, heat exchanger, condenser, evaporator
11. HVAC and refrigeration pipes, pipes and components
12. Lighting: street lights and signs
13. Construction: staircase handrails, guardrails, scaffolding, etc.
14. Fitness and leisure equipment: trampoline, beach chair, boat awnings, treadmill
15. Medical equipment: medical beds, wheelchairs
16. Bathroom: faucet, wall-hung accessories for bathroom
17. Fences: dog cages, cowhouses, etc. to protect cows, horses, and other livestock and domestic pets
18. Hydraulic system (oil pipes for excavators, cranes, etc.)
19. Children’s playground facilities
21. Aerospace and navigation Industry
22. Others: baby stroller, wheelbarrow, shopping trolley, baby bed, luggage frame, etc
Chapter 4. What are the main types of tube bending machines？
According to the customer’s technical requirements for different pipe outer diameters, materials, pipe shapes, operating conditions, and automation requirements, pipe bending machines are divided into hydraulic NC pipe bending machine, CNC tube bender, twin head pipe bending machine, and roll bending machine.
1. Hydraulic NC pipe bending machine
The hydraulic NC pipe bending machine is also called semi-automatic tube bending machine. It is mainly used for the processing of a product with only a single bend or multiple bends on the same plane. The feed and rotation are controlled manually, the bending arm is controlled by a hydraulic cylinder, and the bending speed is controlled by multiple sets of solenoid valves to adjust the output flow of the hydraulic cylinder.
- The price is cheap;
- The touch screen is easy to set up and operate, with good stability
- The basic bending requirements can be completed;
- The maintenance is relatively simple;
- Rotation and feed require manual operation, which is difficult to automate
- Unable to bend complicated pipes
- The bending accuracy is not as good as CNC
2. Twin head pipe bending machine
Twin head pipe bending machine can bend both ends of the pipe at the same time, which is especially suitable for symmetrical pipe bending. They are usually used to bend car seat frames, motorcycle bumpers, furniture frames, with high production efficiency. In the process of bending the pipe, the twin head pipe bending machine cannot install mandrel and wiper die, therefore, the bent pipe requires a relatively large bending radius and thick wall thickness.
- Simple and easy to operate
- Double-axis synchronous work, good for the symmetrical job.
- Can bend 2-4 pieces at a time, high efficiency
- Unable to bend very large diameter pipes
- Cannot achieve mandrel bending
- Cannot achieve complex bending requirements
3. CNC tube bender
Based on the functions of the semi-automatic pipe bending machine, the fully automatic CNC tube bender adds the functions of automatic feeding and pipe rotation, that is, the distance between multiple bends and the space angle in a product are all digitally inputted through the touch screen. Automatically complete the feeding and pipe rotation, and the processed pipes have high precision.
The CNC tube bender is divided into full electric structure (full servo )pipe bending machine and partial realization servo structure pipe bending machine. The full-electric structure pipe bending machine is completely independent of the hydraulic system. All transmission mechanisms are replaced by servo motors, and all clamping mechanisms, electric control system or pneumatic structure or pneumatic hydraulic control system are also using servo motors, which eliminates the hydraulic system, eliminates the accuracy error caused by the change of oil temperature, no oil pollution, and improves environmental protection conditions.
At present, the Chinese market is still dominated by CNC tube benders with partial servo structures. Full servo pipe bending machines are mainly found in imported high-end pipe bending machines.
According to the number of installed bending tools, the CNC tube bender can be divided into single-stack tool models and multi-stack tools models. Single-stack tool pipe bending machine includes 2-axis and 3-axis.
The 2-axis means that the feeding and rotation are controlled by a servo motor, and the bending is controlled by a hydraulic cylinder.
The 3-axis refers to the feeding and rotation, and the pipe bending all controlled by servo motors.
For special pipe bending requirements, such as multiple bending radii on a pipe, we can use double-stack or multi-stack models to bend. The bending process does not need to be stopped, avoiding the trouble of changing the tool, and can effectively ensure the accuracy and size of the bending pipe. The up and down tool shifting, left and right tool shifting can be controlled by a cylinder or a servo motor.
According to the bending direction, the CNC tube bender can be divided into left pipe bending machine and left-right co-direction pipe bending machine.
- High product accuracy and repeatability
- Easy to operate, suitable for high volume production
- Multi-layer dies can be installed for multi-curvature, multi-diameter, mixed bend, enabling the bending of more complex tubing.
- An automatic loading or unloading device can be installed for unmanned automatic operation.
- Relatively expensive
- Requires the operator obtain some expertise
4. Roll bending machine
The roll bending machine is suitable for rolling processing of pipes and profiles with a large bending radius. It can process product shapes such as arches, coils, etc., and is mostly used in industries such as bridges, stadiums, engineering buildings, and street lights.
The most common type is 3 roller pipe bending machine. There are also 7 rollers and 9 rollers bending machine.
- A variety of tube radii can be performed on the same machine including variable angles.
- Sections such as pipe, bars, and angle can also be formed with this method
- Slower process as each tube is manually processed with difficulty in obtaining exacting results.
- Thin-walled tubing can easily collapse if the bend radii are too small.
- Accuracy and repeatability are not very good
The above are the four types of pipe bending machines, under each type, according to the maximum bending capacity, the pipe bending machine is divided into several models, so when buying a pipe bending machine, if you do not know the specific model you need, it is better to provide product drawings to suppliers and ask them to recommend the right model for you.
Chapter 5. What drive systems pipe bending machines adopt？
Pipe bending machines usually use the following types of power source systems. Hippo will briefly introduce and analyze the advantages and disadvantages of each method, hoping to help you choose a pipe bending machine.
1. Pure hydraulic system
This system is mostly used in semi-automatic pipe bending machine, using hydraulic oil as the medium, and the electric motor refueling pump as the power core, through the hydraulic valve group, to control the movement of the cylinder to achieve the overall motion system of the equipment.
- The technology is mature. The system has been used and developed for at least 30 years. As long as qualified quality hydraulic components are used, the failure rate of the entire system is extremely low.
- The pressure is stable and the action is consistent.
- Large transmission power and relatively fast response speed
- Economical and practical
- It is difficult to achieve precise motion control.
- High energy consumption. As long as the device is turned on, whether it is active or not, the device will maintain high power consumption.
- The system generates a lot of heat.
- The hydraulic oil needs to be replaced regularly.
- When the oil temperature of the hydraulic system is different, the accuracy of the bent pipe and the rebound coefficient are different
2. Hydraulic + servo system
This system is mostly used in fully automatic CNC tube benders. The hydraulic action drives the clamping and mandrel pulling actions without precision requirements, and the precise action control is carried out through the servo motor, such as pipe bending, feeding, pipe rotation, tool change, etc.
- Can be used for precision pipe bending machines.
- Reduced energy consumption, because the servo motor shares part of the actions that were originally hydraulically driven.
- The price is not very expensive, users can accept it.
- The system generates a lot of heat.
- The hydraulic oil needs to be replaced regularly.
- The energy consumption is still relatively large.
3. Pneumatic + servo system
This kind of system is mostly used in small automatic pipe bending machine. Cylinders control clamping, mandrel pulling and other actions without precision requirements. Servo motors are used for precise action control, such as pipe bending, feeding, pipe rotation, tool change, etc.
- Can be used for precision pipe bending machines.
- The energy consumption is greatly reduced.
- The system generates little heat.
- Quick action and high production efficiency.
- Because the cylinder output is too small, it is mostly suitable for small pipe bending machines.
- The working noise is relatively high.
- There are certain requirements for compressed air quality.
4. Full servo system（full electric)
The system is that all actions of the whole machine, all driven and controlled by servo motors, completely abandoning the hydraulic system, including auxiliary push, wiper dies, etc. The advantage is that there is no hydraulic system caused by oil temperature changes. The instability error is stable, the running speed is stable, the noise is reduced to very small, and there is no oil circuit pollution. At present, there are very few all-electric pipe bending machines on the market, and they often appear on imported pipe bending machines. Many domestic manufacturers are developing such new products, but the prices are relatively expensive, and stability and reliability need to be further tested by the market.
- High precision, high controllability, flexible action combination.
- The energy consumption is greatly reduced.
- The system generates little heat.
- Quick action and high production efficiency.
- High hardware cost is high.
- The system cost is high, and it needs to be supplemented by a high-end pipe bending machine system to take advantage of the multi-servo.
Chapter 6. What control systems does a tube bending machine use？
The pipe bending machine usually uses the following methods as the carrier of the control system: microcomputer chip (NC control system), PLC control system, industrial computer system, PLC+ industrial computer system.
1. Microcontroller system (NC control system)
The action of the hydraulic pipe bending machine is integrated on a circuit board chip, and the system is completely locked, that is, it can only be used and cannot be modified. But the advantages are obvious, the principle is simple, the components are few, the price is good, and it is used in most single-end pipe bending machines. In addition, the single-chip microcomputer has also been maturely applied to pipe end forming machines, rolling machines, pipe cutting machines, and other equipment.
2. PLC control system
The control system is a mainstream system with PLC as the core of the system and a touch screen as the display carrier. The system has a high degree of openness and powerful functions and is suitable for automatic pipe bending machines. Most automation equipment on the market today uses this system, and the system is also very suitable for online use with robots.
3. Industrial computer system
The industrial computer system is a system based on an industrial computer as the core and an industrial touch screen as the display carrier. The system has high specificity. Compared with the PLC system, the industrial computer’s strength is the calculation function, which can easily realize multi-axis linkage and simulation. Simulation and display function.
4. PLC+ industrial computer system
This is in line with the hardware architecture of the international general machinery and equipment, and it combines the computing of industrial computers, the high openness of PLC programming, and the stability of motion control. This structure can further improve the performance of the pipe bender, improve the continuity of action, and the response efficiency of the equipment.
Chapter 7. How does a pipe bending machine work?
In the pipe bending process, the pipes or profiles are bent around the center bending die. The bending die is installed on the main shaft. The clamping die clamps the pipes to prevent the pipes from moving. The pressure die presses the pipes with appropriate pressure, the mandrel fills the cavity of the workpiece to prevent wrinkling, flatness, thinning, and other failures when the tube is bent. When the shaft rotates, the tube is wound on the bending die and bends with the shaft rotation, and then the workpiece is fed and rotated. The bending radius is determined by the radius of the bending die. If you want to get different bending radii, you only need to replace the pipe bending tools with different radii.
Chapter 8. What pipe bending tools are used in pipe bending machines？
When we use the pipe bending machines, the indispensable tool is the pipe bending tools. The design of the pipe bending tools is very particular. For example, bending stainless steel thin-walled pipes is technically difficult, so the tools must be revised and adjusted repeatedly.
Only the tools design is reasonable, the pipe bending machine can bend reasonably.
1.Pipe bending tools types
For common hydraulic semi-automatic pipe bending machine and fully automatic CNC tube benders, a full set of tools include:
(1) Ordinary bending die -designed according to your bending radius
⑵ Clamping die-designed according to the minimum straight section length allowed by your bending product.
⑶ Pressure die-designed according to the maximum bending angle of your product.
⑷ Mandrel-according to your pipe diameter to match the appropriate gap, the mandrel has a variety of connection forms, it is necessary to design the number of mandrel ball according to the bending radius R and bending angle of the product.
⑸ Wiper die-according to the material of the pipe, the material is generally selected (A3/20#/45#/tin bronze) according to the pipe diameter/bending radius
⑹ Collet—used for fully automatic models.
In addition, for some special products, such as the two bends of the product are too close and the straight section is short, which makes it impossible to clamp, it is necessary to design an integrated compound bending tools.
For products with multiple different bending radii, we need to design multi-stack tools, switch the tools up and down, left and right, so that it can be processed at once.
The material of the pipe bending tools needs to be made according to the material of your pipes. For different parts, the materials are different, mainly depends on the strength, toughness, and wear resistance of the tools.
(1) For bending die/clamping die/pressure die, 45#, CR12, CR12MOV, 42CRMO can be used. Under normal circumstances, dies made of Cr12MoV can meet the needs. Of course, if the dies made of 42CrMo with higher prices are used, the quality of the production will be better. This is because 42CrMo is a higher strength alloy. High-quality steel has very good strength and toughness and can be processed and produced at a temperature of about 500 degrees.
When bending aluminum profiles, it is best to use nylon for clamping and pressure dies to ensure the strength of the tools without scratching the aluminum surface.
(2) For wiper die, too hard nor too soft would be not good, so we usually use copper alloy to make wiper dies.
Hippo pipe bending tools are all quenched (heat-treated tools are more wear-resistant than ordinary tools), and the machining dimensional tolerances of all key parts have reached high precision, which can provide you with the best bending process, thereby the processing cost is reduced, and the degree of standardization is high. The quenching process of the tools is very particular. If the quenching temperature of the tool is too high, the quenching method and time are unreasonable, and the tempering temperature and time are not selected properly, the pipe bending tools will be damaged after entering the bending production. Hippo’s tools quenching process is very mature, which can guarantee durability.
1）What does mandrel bending mean?
Mandrel bending is a method of inserting steel rods into the tube to provide support during bending. This method can bend the tube perfectly, prevent the tube from flattening, and allow the tube to be bent without wrinkles or kinks.
Not all tube bending requires a mandrel. Generally, smaller diameter tubes (such as 6-8 mm tubes) have more support on their own and do not need to use a mandrel. In addition, some galvanized pipes and iron pipes with large bending radius and thick wall thickness do not require a mandrel. However, for thin-walled tubes with a small bending radius and a large diameter, the inner wall of the tube should be supported by a mandrel to prevent its cross-section from becoming elliptical and wrinkling on the inside.
2）When mandrel is needed？
Hippo has summarized a formula based on long-term practical experience, which can help you quickly determine whether a mandrel is needed to complete the bend.
D is the outer diameter of the tube, T is the wall thickness of the tube, and R is the bending radius. The difficulty of bending a pipe depends on the wall thickness and bending radius of the pipe. The smaller the wall thickness and the smaller the radius, the more difficult it is to process.
We use relative wall thickness tx = t / D and relative bending radius Rx = R / D as the bending process parameters. For pipe fittings with Rx>3D and tx>0.04, standard tools can be used. For pipe fittings with Rx <3D and tx <0.04D, mandrels, wiper die and other technical measures can be added to ensure bending quality.
3）How to choose the right mandrel？
With mandrel bending is relatively technically difficult, how should we correctly use mandrel bending to enhance the quality of the bend?
① The first is to determine the type of mandrel.
In general, the mandrel can be divided into two categories: one is the hard mandrel and the other is the soft mandrel.
For hard mandrels, the cylindrical mandrel (or cylindrical ball-head mandrel) has a simple shape and is easy to manufacture, so it is more common than claw-shaped mandrels.
For soft mandrels, the spherical node mandrel is very flexible and can swing in any direction, and can adapt to various deformations. Therefore, the spherical node mandrel is often used when bending thin-walled or small bending radius pipes.
At the same time, we have to decide the ball joint quantity according to different relative bending radii, relative tube wall thicknesses, and bending angles. If the number of ball joints is small, the expected effect cannot be achieved; If the number is large, it is difficult to manufacture and it is not convenient for the pipe to penetrate.
② The second is to determine the size of the mandrel ball.
The gap between the mandrel and the tube’s inner diameter is also an important factor affecting the quality of the bend. If the mandrel ball diameter is too small, the tube inside may occur wavy wrinkles, can’t play a role in preventing the tube outside from flattening; If the diameter is large or the mandrel ball outside is not smooth enough, the tube wall would be strained, or even break.
In a word, the selection of a reasonable mandrel diameter and its adequate lubrication are indispensable elements for the quality of the bend.
You could refer to the following empirical formula: d ≈ (0.94 to 0.98) D to decide the mandrel ball size.
d- mandrel diameter
D- tube inner diameter size.
③ The third is to ensure the mandrel toughness and lubrication
In order to avoid scratches on the inner wall of the tube, the mandrel shall be sufficiently tough and carefully deburred and polished; the inner lumen of the tube shall also be carefully cleaned and, if necessary, wet-blown sand. The arbor should also be rigid enough to avoid creases caused by shaking, and the proper lubricant should be used.
4) How to use the mandrel correctly
The position where the mandrel penetrates into the pipe and begins to bend seriously affects the quality of the bent pipe.
If the punctured position is too far forward, the pipe outside material would be easily get stretched and can be thinner.
If the penetration position is too far back, the corresponding supporting effect cannot be achieved, and the tube easily collapses, and even wrinkles on the inside.
So, how exactly do we get this right? In fact, we can combine a formula to select: e ≤ (1/4 ~ 1/2) D. The letter e in the formula represents the position where the mandrel penetrates into the pipe at the beginning of bending, the letter D represents the inner diameter of the pipe. hen the specific value can be obtained by calculation.
Finally, after determining the position scale, we should first conduct a trial bend based on this value. During the trial bending process, make appropriate adjustments in accordance with the specific conditions, so that the mandrel reaches the appropriate position. In this way, the resulting bending products can be satisfying.
In addition, when bending square (rectangular) pipes, the cross-section shapes of the mold and the mandrel are different from the round steel pipe, but the selection and use of the mandrel and the bending method are basically the same.
5）Why after use mandrel, the bend still have wrinkles?
Sometimes even when a mandrel is used, wrinkles occur when the pipe is bent.
The following are six main causes of wrinkles when pipes are bent:
①The tube slides in the clamping die
②The mandrel is not far enough
③The wiper die is not installed correctly
④ Wiper die is worn or not fit
⑤The gap between the mandrel rod and the tube is too large
⑥Improper or an excessive amount of lubricant
If both the mandrel and the wiper die are in place, check the pressure inside. You may need to apply more pressure on the dies to keep the tube. Slowly adjust until there are no wrinkles.
4. What should I do if the mold is worn out?
We will debug all the bending tools before they leave the factory, so in your daily use, there will be no major problems when you follow our instructions.
However, because the bending tools are wearing part, in the process of long-term use, there will still be a certain amount of wear. The worn bending tools will have problems such as non-standard bending angle and deformation when bending the pipe. If you find the above problems, you should contact us to re-customize the tools.
In addition to the long-term use of wearing, there are the following reasons also cause the tools wearing.
1) The material of the tools is inappropriate
2) The quenching process of the dies is unreasonable
3) When using the pipe bending tools, the position and direction of the parts are installed incorrectly or the bolts are not fastened
If you encounter tool wearing problem, please contact us to find a solution in time.
Chapter 9. What is the pipe bend radius?
The bending radius is the bend centerline curvature radius. The bending radius is usually determined according to the design requirements. The larger the bending radius, the higher the smoothness of the pipe. Generally speaking, if the pipe diameter is large and the bending radius is small, it is easy to cause internal wrinkles or cracks during bending, and the bending quality is difficult to guarantee. Therefore, it is generally recommended that the bending radius is 2-3 times the pipe diameter, at least 1.5 times.
For a pipe, no matter how many bends, regardless of the bending angle, the bending radius better to be uniform.
For some other situations, such as narrow assembly space and limited pipeline layout, which leads to the need for multiple bending radii on a pipe, or when the straight section is short, you will need to consider double-stack or multi-stack tools, or compound tools.
Chapter 10. What to consider when buy pipe bending machines？
Here are the important factors to consider before you buy pipe bending machines.
1. Determine the type of tube bending machine. Tube bending machines include hydraulic semi-automatic tube bending machine, fully automatic CNC pipe bender machine, and twin-head pipe bending machines. You need to combine the products you currently need to process (considering the material, thickness, and bending requirements) and future production requirements to determine the type of purchase. This not only affects procurement costs but also affects bending efficiency and bending accuracy. The cost of hydraulic semi-automatic machines is lower, but the bending efficiency and accuracy are not as good as CNC pipe benders. Double head pipe bending machines are more suitable for specific products, and their versatility is not as strong as single-head tube bending machines.
2. Determine the machine capacity. Determine the appropriate machine model according to the pipe diameter, wall thickness, bending radius, bending accuracy requirements, and bending process of the required bend.
3. Select the machine quality and accuracy. After the model and configuration are selected, it is necessary to investigate the manufacturing quality of the pipe bending machine, like the machine structure, the quality of the motor (servo motor), the quality of the rack and pinion, guide rail, and the accuracy of the pipe bending machine.
4. Check the stability of the control system. The CNC system is the heart of the pipe bending machine, and the hardware configuration of the CNC system determines the stability of the CNC system and the efficiency of the pipe bending.
5. The durability of the tools. The material of the pipe bending machine tools and the design is also very important. A good tool can enable you to obtain a perfect bend, ensure the bending quality, and save your future costs.
6. The operation is easy to learn and use. This is the most concerning issue for users. For an enterprise to be profitable, the tube bending machine must be understood and proficiently operated by the operator in a short time, reducing the intermediate links of adaptation and learning, thereby reducing operating costs.
7. Warranty. A good supplier should provide its pipe bending machine with a warranty period of up to 2 years.
Chapter 11.How to choose the suitable pipe bending machine model？
This is the responsibility of the pipe bending machine supplier. We are obliged to recommend suitable models for you in combination with your production needs when you consult. Specifically, to recommend the correct model for your application, we need to know 6 factors. Especially diameter, wall thickness, and bending radius, three are correlated.
carbon steel, stainless steel, copper, aluminum or others?
Outer diameter and wall thickness
①When we talk about bending radius it refers to the radius measured to the centerline of the tube. (If yours is the inner radius, please let us know.)
②Don’t get bending radius and bending angle mixed up! This photo for your reference.
4）MULTIPLE BEND RADII
If there are multiple bend radii, please advise clearly.
(Design with multiple radii only do it if you really need to! Better to use the same radius for one pipe.)
6）ANNUAL VOLUME FOR YOUR PROJECT
Chapter 12. How much does a pipe bending machine cost？
The price of the tube bending machine is a very broad issue, which is related to the type, model, machine configuration (motor brand, hydraulic system, transmission system, etc.) of the pipe bending machine, and the number of tools. Ask hippo team for the accurate pipe bending machine cost！
Chapter 13. How to bend the pipe accurately
You must be very concerned about the accuracy of the pipe when using the pipe bending machine. To ensure the accuracy of the pipe bending, it must first be controlled from the raw materials. It is best to purchase all pipes from the same supplier, preferably the same batch, which helps to keep the pipe size consistent. So how to bend the pipe accurately?
- Choose suitable pipe bending tools. Choose the right pipe bending dies, the pipe bending speed and feed rate can be maintained at a high level, so the accuracy of the pipe bending can be guaranteed.
- Control the tightness of the sprocket chain, which is an important factor affecting the accuracy of the pipe bending.
- Fine adjustment of the tools. Fine-tuning the tools can overcome tools wear and have a good effect on improving the accuracy of the tube bending machine.
- Bend angle measurement and manual intervention of spring back compensation, this method can improve the accuracy of product production
- Compensate the matching accuracy of the slider, the pipe bending head, and the pipe bending arm. During the long-term use of the pipe bending machine, wear is inevitable, but the accuracy of the pipe bending machine can be improved by replacing a small amount of wearing parts.
Buying a suitable pipe bending machine is not an easy task, we hope after reading this guide, you can fully understand all aspects of the pipe bending machine and avoid some problems of importing it from China, after international after sales service is tricky.
Of course, Hippo, we are your reliable partner for purchasing tube bending machines in China.
If you have any needs, please contact us.