Automation and welding
by Prof. R. Sreedaran
Abstract
This article introduces the concept and application of meaningful automation in welding and welding related industries. The introduction of computer and software and the change in the technology has made it easier to adopt automation economically. Indian industries are slowly picking up to meaningful automation by a slow and correct approach in order to take care of the social obligation of employment. The information for this article is collected from various sources and we thank them for allowing us to use the same.
We have to clearly emphasize that we are not replacing the welder, human resources but introducing the methods to increase the productivity and quality with in the form logical, sound, foolproof systems. Robotic automation should be considered only for large mass production items and not for custom made items.
Robotic System for Continuous Welding Consumables
Introduction
Automation refers to any productive, meaningful activity-work with minimal human intervention through computer and mobile digital communications methods. The last 20 years have changed the method and system of working in industries by the introduction of computers. Computer controlled manipulators and robust software has made automation easier and economical. Automation does not refer to removal of human resources, but removing the human resources from dull, dirty, dangerous, difficult work places. The human resources can be utilized for more creative and productive tasks.
Welding Automation
In welding automation focus is given to the following aspects viz
(a) Time saving
(b) Quality
(c) Reduction of scrap
(d) Reduction of fatigue to operator (e) Minimum rework.
The top most priority is safe and comfortable working environment. All these aspects can be achieved by different kind of automation. The process of welding involves different operations namely, cutting, beveling, welding, finish grinding and testing. Automation in welding system should be designed to take care of all these activities.
Indian Industry And Automation
At present Indian industry is facing a tough competition from relatively low priced products from China, Taiwan and other East Asian countries. This is due to cheap labour & industrial policies of the countries. So to survive such competition the better quality and high productivity plays a vital role. Here a meaningful automation is important. Welding plays a major role in all industrial activities.
Welding Rotator
The introduction of continuous welding consumables in mass production items and welding fabrication is a must. It is to be noted that automation both in small, medium, large production not only improves the quality of the product, but also improves the acceptability with the customer. Automation does include fixtures, special holding mechanisms, positioners, rotators, indexing devices which help in achieving better accuracy.
Stick electrodes
Stick electrodes are used in more than 50% fabrication because of the easy availability and meeting the various mechanical, metallurgical requirements. The selection of the right type of fixtures, indexing devices helps in improving the accuracy of fitting and welding .This kind of low cost automation helps in making flanges, pressure vessels; construction items where numbers of items to be made are small in numbers.
Here positioners, rotators play an important role. Welding positioners of various sizes and ranges are available. They are very compact and solid state control with variable speed drive with all safety features and accessories. These devices make welding easy and give more flexibility to the welder. They have the provisions for angular tilting and rotation with forward and reverse motion. These are highly suitable for manual arc welding. It increases the productivity and also reduces the shop rejections.
The present day technology and use of computer and tested software enables easier and trouble free operation for the welder. This type of low cost automation can be very easily introduced in the existing systems. These are available for weight of 1000kgs and above.
Floor Mounted Positioner
Typical positioners are shown which can be remote controlled and can be used for all kind of stick electrodes. Floor mounted positioner shown is a typical example, which shows various objects can be held by suitable fixtures and indexing devices.This facilitate the welder to have an easy acccess to weld in a convinient position.This reduces welders fatigue and improved performance.This system has variable drives and solid state controls, and remote controlled panel for easier maitainence and operation.
The rotator positioner has an universal job holding fixture and an indexing device which accomodates different jobs for welding.The designs are available for light to heavy weight jobs.Custom made designs are also made to take care of the specific needs.
- How to adopt automation;
- Study the welding process.
- Study the quality and quanity of product.
- Study whether automation is justified.
- Select flexible automation method so that cost of autmation is justified.
Continuous welding consumables
Flux cored wire, co2 welding wire and other form of continuous welding wire forms an important aspect in today’s welding where mass production is needed. Here Robotic automation can be considered as it justifies higher capital cost and investments. Automobile industries have standardized on such system for various types welding application in the case of vehicle manufacturing. A typical robotic system is shown at the end of the article.
Conclusion
The introduction of automation in Indian context should be done with utmost care and should not be followed by westeren or advanced countries methods. We have a different social obligations and work culture and that should be carefully blended with approval from the work force.
