Robotic welding or automation is welding process is basic need or current technological era when every machine need precise finishing. When we talk about the welding suddenly a picture appears in our mind that it is the process of joining two metal parts. But to have a better understanding of the topic, welding is not limited to metal and ceramics only. It is also used in the plastic industries for the same purpose to join the two plastic parts.
In manufacturing, the term joining and the assembly comes frequently,
it is commonly used for welding, brazing, soldering, and adhesive bonding to get the assembled entity. This assembled entity is joined permanently and it is difficult to separate it. Joining is one of the most important process of the mechanical industries (aerospace ,automotive , oil and gas). Let us consider oil and gas industries what will happen with oil and gas if the tank is and pipe is joined by some other mean instead of welding, brazing and soldering.
It is the manufacturing process of joining two parts into a single entity using nut, bolt, and fastening and these methods gives the flexibility to dissemble the entity into individual parts. It is very progressive way of joining the parts together. In the floor of manufacturing the assembly lines are sequential organized whether it man power , tool, machine and parts to be assembled. To understand the importance of assembly, let us consider that the whole car parts is join by welding and you want to change the cylinder from the engine?
Welding is the process of joining two individuals parts at the contacting surfaces by using the heat or pressure or filler material and combination of it. Some of the welding processes are achieved by pressure or heat alone. The filler is an Extra material that is used in the welding to make joining strong. The welded parts are called weldment.
Why we require Robotic Welding or Automation in welding?
As we are well familiar with automation, it is the process of doing something efficiently without human intervention. At the same time, it is also very important to know why do we automate the welding process.
Safety and health
It was found that in the welding process that it produces hazardous gases that affect the life of the welder. Generate particular fumes, noise, toxic gases and a certain range of electromagnetic radiation which varies from ultraviolet to X rays. In addition to these methods related to hazard. There is also risk associated with application constraints. If the project of shipyard then it is very difficult for welder and associated team to work underwater and a risky as well. So to overcome with all these applications constrain automatic welding offer to perform all these projects efficiently without compromising the welding quality.
Manual welding does not give efficient and accurate weldment that leads the further process to find out the irregularities, gap, and defects in the welding to achieve the quality and standard set by the client and at last, the whole process consumes more time and capital.
It is very clear that the production of the product directly depends on the manpower skills and the understanding of the process. Many of the research reports found that the demand for skilled welder increasing gradually but there there is not enough skilled welders who can perform the work within the given span of time. Automation in welding is classified as-
- Machine welding
- Automatic welding and
- Robotic welding
Welding automation gives a very vast configuration of the system from simple arrangements to the fully integrated systems some of them are as mentioned below-
- Simple mechanism
- Customize and dedicated automation.
- Robotic welding
- Modular automation
- Programmable control
- Remote control slave.
- Simple mechanism Robotic welding
- An industrial robot is not a humanoid welder.
It is a programmable device specially designed for both manipulate and transport parts and tools through variable program motion to perform the specific task of the manufacturing. As far as welding robot concern tool or specialized manufacturing implementation is grouped of welding head wire feed and tracking device. Here wire a filler material which is feed into the joint to make the welding strong. The tracking system gives direction to the robotic movement. robotic process are now used in many of the welding processes that includes – GMAW, FCAW, SAW, GTAW, plasma, resistance spot, and laser welding, etc.
Components of the robotic welding are asleep follows:-
- Manipulation arm
- Welding package
- Control system
Mechanical manipulation system that gives the common configuration of manipulating and the most common is articulated arm usually having six and more axes of movement and the benefits of this articulated arm are its degree of freedom and flexibility to reach the narrow access area.
There are many systems to drive the robotic arm by the pneumatic, hydraulic and electrical actuator is used for the movement of the arm. Hydraulic power systems are recommended in this because it has to carry the high load more than 35 kg. If this is used for resistance spot welding then the speed must be limited. Now in most of the fusion welding, DC servo motor drive is being used.
The welding package basically depends on the welding operations being used. It varies process to process
- Resistance welding
It is known for pick and place type welding application. Welding head is brought by the robot at the joint location that is being welded. Electrode palaces near on the joint and the welding is being performed. Once the welding done robot moves the next position of the welding and the same is repeated until the desired operation performed.
- Laser welding
Please keep in mind that robotic welding has not changed the composition of the welding it has just the way of the process and eliminates the direct Human interaction. So in the laser welding, everything would be as the traditional welding like co2, etc.
As the name itself says what control system does. It has the following task to perform-
- Provide program storage
- Interface with the operator
- Control the welding package
- Control the welding head position.
Mechanized/ machine welding.
In this welding, process adjustment can be done during the welding process. In this process the welding is being perform under the supervision of the operator. Basically the welding is achieved by moving the welding head mechanically with respect to the stationary work or by moving work and stationary welding head.
Adjustment during the welding is not at all required. Everything is being set and programmed prior to the process start there is no need to have someone for supervision. A person is deployed just to oversee the process and detect the variation from the set condition or normal condition.
I think we late to know the welding mechanization because the pipes welding expert are using these technologies since the 1960s and the TIG welding process still use more or less manual intervention.
Once the welding is done there is the number of inspections methods is being implemented to check the quality of the welding by automation or robotic way of inspection.