Electric metal welding is used to connect metal parts of machines, mechanisms, devices of building structures and carcasses of buildings without additional fastening devices. Work on the erection of metal structures is performed by manual welders. The quality of the connection on new products and during repair work depends on the level of workmanship.
Inaccuracies and negligence allowed in the work lead to premature destruction of structures, accidents on a large scale. The specialist understands the specific features of welding, knows the essence of the process, uses new methods and complex techniques in work. Manual welders work at those business facilities where automatic units cannot be used.
The welding process of two metal surfaces consists in melting with the help of an electric arc the upper layer into which the substance of the electrode penetrates. After cooling, a strong metal seam is formed. Electric welder services are required in almost every organization or enterprise.
Qualities and skills of an electric welder
The specialty of the welder is complex and harmful, therefore, before hiring a person, he undergoes a medical examination in the established framework to identify health problems. The job seeker understands that this is a difficult profession. Manual welder has the following qualities:
- perseverance and hard work achieves the goals in the work;
- is hardy in psychological and physical terms;
- patiently endures prolonged stay in uncomfortable poses and in enclosed spaces;
- has by nature or develops visual perception, vision, knows how to determine the size by eye;
- knows how to deftly and accurately move;
- without fear works at height;
- performs work efficiently and accurately.
Contraindications to the profession include: diseases of the skeletal system, rheumatic complications, respiratory ailments, allergic manifestations, increased blood pressure, visual impairment, insecure movements and tremor of the extremities.
Specialist Tools and Accessories
- Convenient and high-quality electrode holder (lightweight - up to 0.5 kg).
- Mask on the head or shield of the welder to protect the eyes and face from infrared rays.
- Cables for connecting the device to an electric current source and for creating a working arc.
- Manual welders use metal brushes to clean the surface.
- Hammer for beating slag from the seam.
- Chisel to remove weld defects.
- Ruler, square, roulette, set of patterns.
- Special clothes of the welder.
The complexity of the work
In welding, there are certain process violations, expressed in the appearance of deformation stresses from various causes. Partial intermediate heating of the weld, its shrinkage, improper change in the structure of the deposited area and much more contributes to deformations. The manual welder manual provides for the use of a work project in the work, which indicates the design of the welding unit.
To combat process abnormalities, the method of balancing deformation, rigid and durable fastening of parts, preliminary annealing, temperature dressing of the product after welding is used. For various reasons, internal and external defects, cracks, violation of the seam geometry, pores on the surface, undercuts appear.
All violations of the integrity of the seam affect the quality of the connection of the product, a highly qualified welder tries to avoid violations of the technology. Violations that have arisen are necessarily corrected. Some defects are corrected without cutting the seam; on others, the weld is repeated after the mechanical removal of the failed joint.
The duties of an electric welder of manual welding include a thorough check of the quality of the connecting seam, identification of deficiencies, taking into account the allowed tolerances, in accordance with the norms and rules. If the tolerance is not in compliance with the standards, the welder corrects poor-quality work.
Instructions for the protection of labor of an electric welder manual welding
The welder begins work by checking the working condition of the unit, the insulation of the power supply cable and the state of the electrode holder. The next is the arrangement of the workspace for work and listening to safety instructions at the place of work.
Before starting work with the welding machine, the protective grounding of the unit body and the secondary motor winding is checked, without which work does not start. An electric welder of manual arc welding earthing a work surface in the form of a metal table. To protect others, the welder installs protective shields made of non-combustible material.
The work of an electric welder of manual arc welding is fraught with the danger of electric shock, so welding in damp, damp rooms and on metal surfaces must be performed standing on a rubber mat underfoot. Be sure to wear rubber shoes (galoshes, boots), rubber gloves are used. Eyes are protected by welder's glasses or a special mask.
The primary power supply circuit is not made longer than 10 m. Work in the area with flammable substances is carried out in accordance with the instructions for special welding conditions. Repair of vessels of flammable substances is done after cleaning their surface with washing with heated water.
Working electric cables are arranged so that they do not touch metal objects, heated pipelines. They do not weld the walls of pipes that are in the system under the pressure of water, gas, oil, etc. Breaks are made after disconnecting the device from power and removing the voltage from the electrode holder.
An electric welder of manual welding is allowed to work if he has a qualification discharge of at least the second. Work inside closed tanks, tanks and other containers is performed only in pairs, work begins after providing natural or installation of forced ventilation of the workplace.
The welder's overalls are in accordance with the norm and are in good condition. The material is a thick, dense, non-combustible fabric that does not melt from sparks - a tarp is ideal. A warm hat is chosen without a visor that interferes with the proper placement of the working mask. Shoes are worn with a dull top, which prevents a burn from sparks, it is sized and tightly laced. Canvas gloves are put on so that the jacket sleeve is covered.
Non-observance of safety measures leads to various industrial injuries:
- burns;
- lacrimation
- electric shock of varying degrees;
- poisoning by vapors of zinc, silicon, lead, manganese, nitrogen;
- traumatic injuries from explosions;
- irradiation with gamma particles during suturing.
Fire Fighting
An electric welder for manual arc welding always complies with fire regulations. He does not start work until the workplace is provided with fire extinguishing means: a box with sand, a shovel, buckets and a fire extinguisher.
Explosive and flammable substances, flammable materials, and wooden structures are not necessarily protected by sheets of metal or asbestos at or near the workplace. After completion of work, the remains of an open flame are checked and do not leave pockets of flame.
Job description for the welder
A qualified electric welder is included in the category of specialists. The employee is hired and dismissed by the head of the department in agreement with the immediate supervisor. Below we list the main competencies, rights and obligations of the welder, as set out in the job description of a specialist.
Welder knowledge
To qualify for a specialist, a welder has certain skills and knowledge. Manual welders know:
- properties of titanium alloys, their variety and physical properties;
- kinematic device of automatic and semi-automatic welding units, general information about the electronic control filling;
- data on the susceptibility to corrosion of various metals and its causes;
- test methods for finished welded products;
- types of heat treatment of joints and joints;
- general fundamentals of weld metallography.
Job responsibilities
The job description of a manual welding electric welder determines the terms of reference within which the welder works. The specialist performs work in various fields.
It carries out gas, arc and plasma welding of very complex hardware components, parts and structural components of pipelines made of steel, non-ferrous metals, cast iron. It works with alloys designed for use in dynamic and vibratory structures with high pressure.
Performs gas and arc welding of dynamically working building and other structures. It applies automatic welding to join parts from alloyed, titanium alloys on complex modern devices. It makes mechanized welding of structural units of pipelines, joints of buildings working under vibration. Welds ceiling joints and joints on a vertical wall.
Manual Welder Rights
In each enterprise, in accordance with the norms, a manual welder is vested with certain rights, the work of which intersects with other specialists. Employees subordinate to him receive instructions from him in the field of issues within his competence.
The specialist monitors the process of completing tasks, monitors the timing of the execution of orders of his subordinates. An electric welder has access to all necessary materials, documents according to the nature of his activity and the work of subordinate links. The employee interacts with the technical support services of the enterprise and production departments.
He has the right to familiarize himself with the orders and decisions of senior employees on issues of their own activities. It offers innovative ways to improve welding techniques and submits to competent services. Based on the results of the work done, he offers for consideration by the head a list of employees who have distinguished themselves in their work, and also asks to consider the question of punishing violators. Reports to the immediate supervisor about all unplanned changes in technology and emerging shortcomings.
Welder Responsibility
The welder, within the limits of the legislation, is responsible for the following actions:
- poor performance of work or failure to perform official duties, violation of the internal regulations of the enterprise;
- legal violations provided for by criminal, civil and administrative laws;
- damage to the material plan;
- non-observance of trade secrets of the enterprise and confidentiality;
- failure to comply with safety standards and labor protection.
3rd category manual electric welder
The specialist performs manual and arc plasma welding, makes a seam of medium complexity, makes up units of carbon and structural steels, non-ferrous materials. It works in any position of the selected connection, except for the ceiling. Makes oxygen cutting of parts of medium complexity from alloy steels and low-carbon iron, non-ferrous metals. Fuses worn tool parts made of structural and carbon metal.
Knowledge and skills determine the categories of manual welder. The specialist is well versed in the design of electric welding machines and chambers of welding equipment, knows the requirements for the quality of the seam and the surface of parts after cutting. He knows how to distinguish the properties of electrodes of various types, knows techniques for determining the quality of the suture joint. The worker understands the causes of internal structural stresses and prevents them.
4th category manual electric welder
A worker of the 4th category performs plasma welding of parts, structures, pipelines of medium complexity from cast iron, non-ferrous alloys, carbon metal in all positions, including the ceiling location of the weld. Makes cutting of cast iron, non-ferrous metals, special steels, high-carbon alloys. Able to weld heated pipes and tanks, chips of machine parts, assemblies, tools. Understands in complex drawings.
He knows the principle and schemes of electric welding equipment, the features of working with apparatuses for alternating and direct current, the technology of welding in chambers, the basics of electrical engineering, the mechanical characteristics of metals.
5th category manual welder
It performs manual plasma and arc welding of complex assemblies, structures and piping assemblies from various steel grades; it is allowed to connect building structures operating in difficult conditions. The job description of the electric welder of manual welding of the 5th category indicates that the specialist is welding the block structures in any position of the seam. Makes correction of defects of complex nodes by fusing the missing parts. The welder reads complex drawings of spatial structures made of metal.
6th category manual welder
The welder specializes in connecting complex units and apparatuses, pipelines from any type of steel or alloy, and is allowed to build dynamic building cores and technological vibration structures. Welds seams in experimental structures made of metals with poor weldability, titanium and its alloys. He knows the design scheme of working equipment.
It uses knowledge of the mechanical properties of metals, types of damage from corrosion, the causes that cause them. It applies in practice the fundamentals of weld metallography and heat treatment of compounds.
In conclusion, it should be noted that the work of the welder is complex, the work of structures without accidents and breakdowns depends on it. The specialist has good health and is allowed to work after passing certain standards.