In this article we have discussed about the difference between welder and welding operator, purpose of their qualification and how ASME section IX divided the welding in manual, semi-automatic, machine and automatic welding.
ASME section IX gives requirement for the qualification of the personnel engaged in welding. Section IX divided the personnel engaged in welding as welder and welding operator and gives different criteria and variables for the qualification of them.
Purpose of Performance Qualification
The purpose of Performance Qualification of welder is to determine the ability of the person using a material joining process to produce a sound joint.
In Operator Performance Qualification, the basic criterion is to determine the ability of the operator to properly operate the equipment to produce a sound joint.
Welder and Welding Operator Definition
What is a welder: One who is performing manual or semi-automatic welding is called a welder.
What is welding operator: One who operates a machine or automatic welding equipment is called a welding operator.
As defined above the welder and welding operator is dependent on the technique of welding being used. So to understand the difference between welder and welding operator one shall understand difference between manual, semi-automatic, machine and automatic welding. We have described these terms below with pictures so difference can be understood easily:
Difference Between Manual, Semi-automatic, Machine and Automatic Welding
Manual Welding: Manual welding is type of welding technique in which entire welding operations are controlled by hand i.e. the electrode holder, welding hand torch and blowpipe is controlled by hands only. No mechanical devices are used to control these equipment is used. The examples of this technique are SMAW & Manual GTAW arc welding.


GTAW Manual Welding
Semiautomatic Welding: Semi-automatic welding is one in which equipment used controls the filler metal feed but the advance of the welding is manually controlled i.e a wire feeder is attached to the welding equipment which advances the filler metal continuously through welding torch and the torch is controlled manually for the welding. The examples of this welding technique are FCAW , GMAW and GTAW welding with fire feeder as shown in below figure

Machine Welding: Machine welding is defines as the welding done with the equipment that has controls that can be adjusted by the welding operator , or adjusted under the welding operator’s direction, in response to changes in the welding conditions. The torch, gun or electrode holder id held by a mechanical device i.e. in this technique all of the welding operations is controlled by either of mechanical or electronic devices and welding operators may manually vary during welding as per the configuration of the welding joint to create sound weld. The examples of this welding technique are SAW, GMAW, FCAW and GTAW when the torch and is held mechanically and feed of filler metal is controlled electronically and welding operators manually alters parameters only when required to produce sound weld. Below pic demonstrates the machine welding operation.

Automatic Welding: Automatic welding is defines as the when welding is done with the equipment which perform the welding operations without adjustment of the controls by a welding operator i.e welding operator do not require to control parameters in this technique during welding instead of that before start of welding program is made in which welding parameters are preset and performed by the welding equipment automatically during the process. The example of this kind of welding is robotic welding in which program is stored before welding and operator just need to start the program and all the welding activities will be done automatically. Loading and unloading may not be done by welding equipment. Image below describes the automatic welding

The definition reference is taken from ASME BPVC section IX, AWS 3.0 & BS 499-1. You may check these codes for standard definitions applicable.
Also visit our other posts at below links for more knowledge