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Detailed Description of the Welding Process

Author: Jessica

Sep. 22, 2022

71 0 0

Tags: Transportation

Thermit Welding Consumables

Exothermic welding provides a superior solution through permanent molecular bonding. Exothermic welding is the preferred linking method in many industries because of its inherent molecular-level reliability for conductors and joints. The Exothermic Welding Materials Manufacturer from China provides Exothermic Welding Materials for railway welding construction teams, railway contractors, railway procurement departments, railway supply trading companies, etc.

Welding requires no external heat or power source
Does not loosen or increase resistance over time
Conducts electricity better than the conductor itself
Will not corrode, oxidize or degrade over time
Compatible with copper, steel, coltan, bronze, iron, copper-clad steel, stainless steel, Monel, niobium, brass, and silicon bronze
Requires no special skills
Highly portable
Reduced labor costs


Exothermic welding process

Exothermic welding is a process for joining similar metals that uses an exothermic reaction (a chemical reaction that releases energy in the form of extremely high temperatures and light) of aluminum thermite (metal powder) to heat the metal and permanently join it. The exothermic process involves a chemical reaction that releases heat and does not require an external heat source. A lightweight clip-on die is used to safely position and accommodate any welds required.

The exothermic reaction produces an intense miniature furnace with temperatures over 2,500°F, instantly generating a flow of molten metal into the weld cavity, filling any available space. After waiting a sufficient amount of time after the initial process, the die can be released and the completed joint removed.

Two types of crucibles for aluminum thermal welding of steel rails

Disposable crucible technology: Soldering materials require solder, sand, high-temperature matches, sealing sand and disposable crucible.
Multi-purpose crucible technology: Soldering material requires solder, sand, high-temperature matches, sealing sand, multi-purpose crucible holder, multi-purpose crucible liner, as well as self-fusing plugs and sealing sand.



Molecular formula

3Cu2O +2Al → 6Cu + Al2O3 + HEAT
Copper oxide + aluminum → copper + aluminum oxide (slag) + heat
Reaction temperature approx. 2500°C (4500°F)

If performed correctly, the exothermic solder connection is homogeneous after cooling, which means that a true solder has been formed and the components are completely fused. The connection is permanent and irreversible and does not require additional methods to hold it together.


Advantages of the exothermic welding process for building railroads

Low resistance is maintained over time due to the fused connection.
Does not deteriorate over time due to limited susceptibility to corrosion.
Outlasts the life of the conductor it is connected to.
Eliminates any risk of loosening due to molecular bonds.
Will resist repetitive fault currents.
Provides the lowest possible ground path resistance.
Can be visually inspected for quality control.
Is safe and easy to use, requiring minimal training and protection requirements.
UL® meets UL 467 standards.
Exceeds the requirements of IEEE 837.

Our Advantages

1. tensile strength of welded joints is 5%~18% higher than peers
2. Welding quality testing meets railroad requirements.
3. Three-piece die sand type can meet the welding requirements of rail cross-section, weld width, and the use of special processes
4. Price is 8%~25% lower than peers.
5. Free training, humanized service.
6. Free samples

Application areas

Steel rail aluminum heat welding flux is mainly used in railroad line maintenance, line overhaul, and new line construction.
Use scenarios: such as railroads, subways, factories' lifting rails, elevated railroads, city rails, etc.

Main export countries

Philippines, Vietnam, Thailand, Indonesia, Singapore, Malaysia, Myanmar, Laos, Cambodia, Sri Lanka, Korea, Russia, Turkey, Tajikistan, Pakistan, Bangladesh, etc.

Product Customization Service

China railway line, generally 50KG/m, 60KG/m rails, lifting rails QU120, QU100, QU80, QU70, the international use of more models are UIC60, UIC54.
According to the customer's rail type, we can make sand design and special customized rail type with a minimum order quantity of 300 sets.



Thermit Welding Consumables / Exothermic Welding Materials

Thermite Welding Powder: Thermite powder is a pyrotechnic composition usually consisting of metal powder and metal oxide. Thermite welding powder is not usually explosive, but it does create extremely high temperatures in a very small area for a short period.
Sand Mould: Preformed refractory receptacles that are placed around the rail at the gap to be welded and which receive the molten metal from the crucible.
Luting Sand: Luting Sand's Main material is SiO2. It is used to seal the gap of the sand mold, to avoid the liquid steel leaking.
One-Shot Crucible: One-Shot Crucible of the inner crucible is MgO, and the outside is a steel plate barrel. It is used as the reacting container of portion powder.
Crucible Lining: Crucible Lining is sintered at a very high temperature, so it should be protected from any moisture at all times, otherwise it may cause failure when welding.

Exothermic welding consumables work with rail welding equipment and rail welding tools during rail welding jobs.


Welding Consumables Procurement - When you buy Exothermic Welding Materials, we provide online after-sales service for free!

We can't reach the site because of the epidemic, so we provide online technical guidance, technical training, technical support, remote guidance, teleconferencing, and other services for free! (Get free guidance)

Thermite Powder/Thermite Welding Powder

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