Orbital welding is Automatic Tunguston inert gas welding. It eliminates odds of manual errors in welding. It creates identical welds for hundred of times hence accuracy in welding. – Orbital Welding
Orbital welding was first used in the 1960`s if the aerospace industry recognized the requirement for a superior joining strategy for aerospace hydraulic lines. A mechanism originated in which the arc from a tungsten electrode was rotated round the tubing weld joint. The arc welding current was regulated with a control system thus automating the complete process. The result was a more precision and reliable method compared to the manual welding method it replaced.
Orbital welding became easy for many industries in early 1980`s when combination power supply / control systems were developed that operated from 110 V AC and were physically sufficiently little to be carried on your travels on a construction site for multiple in-place welds. Present day orbital welding systems offer computer control where welding parameters for a variety of applications can be stored in memory and called up when needed for a specific application. The relevant skills of a certified welder therefore are built into the welding system, producing enormous variety of identical welds and leaving significantly less room for error or defects.
Orbital Welding Equipment
In the orbital welding process, tubes / pipes are clamped in position and an orbital weld head rotates an electrode and electric arc across the weld joint to make the required weld. An orbital welding system includes a power supply and an orbital weld head.
Power source: The power supply / control system supplies and controls the welding parameters based on the specific weld program created or recalled from memory. The energy supply provides the control parameters, the arc welding current, the ability to drive the motor in the weld head and switches the shield gas (es) on and off as necessary.
Weld Head: Orbital weld heads are normally of the enclosed type and supply an inert atmosphere chamber that surrounds the weld joint. Standard enclosed orbital weld heads are practical in welding tube sizes from 1/16 inch (1.6mm) in order to six inches (152mm) with wall thickness` of up to 0.154 inches (3.9mm) Larger diameters and wall thickness` could be accommodated with open style weld heads.
The Physics with the GTAW Process
The orbital welding process uses the Gas Tungsten Arc Welding process (GTAW) because the source of the electric arc that melts the beds base material and forms the weld. In the GTAW process (also referred to as the Tungsten Inert Gas process – TIG) an electrical arc is established between a Tungsten electrode and the part to be welded. To begin the arc, an RF or high profile signal (usually 3.6 or 7 KV) is used to break down (ionize) the insulating properties of the shield gas and make it electrically conductive to be able to pass through a tiny quantity of current. A capacitor dumps current into this electrical path, which cuts down on the arc voltage to a level the location where the power supply can then supply current for your arc. The power supply responds to the demand and provides weld current to keep the arc established. The metal to become welded is melted by the intense heat of the arc and fuses together. – Orbital Welding
Reasons for Using Orbital Welding Equipment
Many reasons exist for for using orbital welding equipment. The opportunity to make high quality, consistent welds repeatedly at a speed close to the maximum weld speed offer benefits to the user:
o Productivity. An orbital welding system will drastically outperform manual welders, many times paying for the cost of the orbital equipment in one job.
o Quality. The grade of a weld created by an orbital welding system with the correct weld program will be superior to that of manual welding. In applications including semiconductor or pharmaceutical tube welding, orbital welding is the only means to attain the weld quality requirements.
o Consistency. Once a weld program has been established an orbital welding system can repeatedly carry out the same weld hundreds of times, eliminating the conventional variability, inconsistencies, errors and defects of manual welding.
o Orbital welding works extremely well in applications in which a tube or pipe to be welded cannot be rotated or where rotation with the part is not practical.
o Orbital welding can be utilized in applications where access space restrictions limit the physical size of the welding device. Weld heads can be utilized in rows of boiler tubing where it could be difficult for a manual welder to use a welding torch or view the weld joint.
o Many some other exist for the use of orbital equipment over manual welding. Examples are applications where inspection from the internal weld is not easy for each weld created. Start by making a sample weld coupon that passes certification, the logic holds when the sample weld is acceptable, that successive welds created by an automatic machine with the same input parameters also need to be sound.