Rolling Process Of Roll Forming Machine
Cold rolling is a metal processing method at a temperature below the crystallization temperature, i.e., metal processing at normal temperature (Tcan Tktl ). The product of cold-rolled steel has a thickness ranging from (0.08 1.0)mm.
Compared to hot rolling, cold rolling has the following characteristics:
The technological process of cold rolling is much more complicated, it includes many stages from preparation of the blank to refinement and requires many complex equipment.
Due to the large deformation resistance of metal in a cold state, it consumes a large amount of energy (force F, rolling torque M, engine power P). Friction between the rolling material and the rolling axis is high, so the rolling axis surface wears quickly, requiring a special, high-wear-resistant axis.
The metal’s ability to be compressed is low, thus resulting in low productivity.
Cold rolling causes metal grain to fracture, and crystal lattice to become distorted, resulting in increased metal strength (hardness). Depending on the degree of increase in hardness of each material, each metal can only be cold-rolled to a certain degree of thickness reduction. If we continue to roll beyond that, cracks, fractures, and breaks will occur in the rolled sheet. To overcome this, we perform intermediate annealing to restore the original mechanical properties. However, it must be done within a certain thickness range that the machine can handle.
When rolling, the generated stress must be much lower than the allowable yield strength of the material axis.
To achieve high quality and mechanical properties of cold-rolled sheet products, the technology must be carried out with strict procedures, good equipment, and high-precision machine operation with minimal vibration.
The mechanical and physical properties of the metal after cold rolling increase because the mechanical and physical properties of the metal change when cold-rolled, and the metal organization before deformation has a form of grains, meaning the metal has isotropic properties (all properties in all directions are the same).
However, after deformation, the grain structure is broken, elongated in the rolling direction, and has a fiber-like or filament-like form, meaning the metal has anisotropic properties (properties in different directions are different).
4. The operating principle of roll forming machine
As a model machine, it can only roll 3-wave steel, so we use cut steel sheets. The initial flat sheet is fed into the guide table and then pushed to the pair of driving rollers. This is the initial feeding mechanism often made of 2 circular shafts with a diameter of 40, covered with rubber. When it is necessary to create pulling force, the flat sheet is inserted into the gap between the 2 shafts (the lower shaft is the driving shaft), adjusting the gap will create a pressure from the upper shaft down.
Thanks to the friction between the 2 rubber rollers and the sheet, the sheet is driven through the first rolling pair, the lower shaft is fixed, while the upper shaft is mounted on a sliding plate in a U-shaped groove on the machine body for adjusting the gap between the 2 shafts to ensure that the gap is the most reasonable. After passing through the rolling system, the product is formed with waves as required.
Operation and maintenance of the machine:
Only trained workers are allowed to operate the machine.
Before operating, check the safety systems such as the covers of moving parts, electrical safety conditions such as voltage, fuses, relays, wires…
Perform lubrication and maintenance before each shift and clean the machine before starting work.
Before putting the machine to work (with load), run the machine without load from 1 to 3 minutes to check the transmission parts.
5. Benefits of using a roll forming machine
Roll forming machine not only increases productivity but also saves costs for businesses. With advantages such as high rolling speed, high productivity, automation, the machine provides practical benefits:
Ensuring that the roll forming machine is rolled according to customer requirements, thereby increasing customer trust and revenue for the business. The machine can roll sheets of different thicknesses, colors, and materials according to customer orders.
Helping businesses save labor and insurance costs: The cost of a sheet metal rolling machine is reasonable, fully automated, and does not require many labor resources to operate.
Helping businesses save on maintenance and repair costs: If a good quality sheet metal rolling machine is purchased, it can significantly reduce maintenance and repair costs, thereby increasing productivity.
Saving costs leads to reduced prices, increasing competitiveness in the market.
The machine usually runs stably for many years, so businesses do not have to plan for frequent replacement
6. Choosing a suitable roll forming machine is a prerequisite
Currently, there are many types of metal sheet rolling machines available on the market, and selecting the most suitable one for a company’s production model is still a question that many investors are concerned about.
6.1. Choosing a rolling machine based on the practical needs of the company
The first thing to consider when choosing a metal sheet rolling machine is to calculate the actual production needs of the company, as each sheet production unit will have different customer segments, and each customer segment will correspond to the use of different types of sheets.
Choosing the most suitable metal sheet rolling machine for the production needs will help the company optimize the investment cost of machinery, save labor costs, and save production costs.
The questions to be asked are:
• What type of roll forming machine should be chosen to fit within the given workshop area?
• What is the maximum and minimum length and width of the sheet that can be produced?
• What is the material being processed?
• What is the thickness of the sheet tole?
• Is the price of the metal sheet rolling machine suitable for the financial capacity of the company?
Based on this information, the supplier will advise the customer on the most suitable and cost-effective metal sheet rolling machine.
6.2. Choose a reputable supplier of rolling machines with a well-known brand on the market
In addition to the issue of usage needs, the brand of the rolling machine is also a significant factor influencing the investment decision of most customers when choosing. When companies introduce good product lines to the market along with favorable pricing policies and good after-sales service, they will build a reputation and brand for their products.
Therefore, choosing a product based on the brand is not just following the majority, but it is also based on the experiences of other investors who have purchased and used the product and left a good impression about it. This is something that investors evaluate the quality of the rolling machine.
6.3. Consider the after-sales service and warranty of the supplier
Finally, a crucial factor that customers need to pay attention to is the after-sales service and warranty of the supplier. Vietsteel Machinery Co., Ltd understands that for technical machinery products, after-sales service and post-sale care are essential. Installation or repair, and warranty services are carried out by a team of knowledgeable, experienced, and enthusiastic staff. Vietsteel commits that when the machine has any problem, the technical team will be present promptly to avoid affecting the production progress of the factory.