To pull down a building, the concrete is crushed using an excavator, and then the steel is cut with an oxyacetylene torch. Though, excavators cannot be used in various high-rise structures, also the oxyacetylene torch cannot deal with concrete demolition. Working for concrete demolition and pulling down of mining closure is a dangerous task, and thermic lance-using construction businesses are ignorant of what to look for to ensure safety. There is a knowledge gap about the use of thermic lances to deal with hardened concrete demolition. It is optimal for the customers to find a suitable method to have concrete demolition and steel structures with highly considered safety and security for old high-rise buildings that cannot be demolished by excavators because of lack of sufficient space.
In this content, we’d like to discuss about thermic lance and its one of the various solutions for cutting hardened concrete structures in high-rise buildings not including the use of an excavator.
Thermic Lance and the Demolition Test of Concrete Structures
Source: Daiwa Lance International
Demolition Works
Demolition is the process of pulling down, wrecking, or destroying a building or structure, in whole or in part. Construction work is described as any task related to the demolition of a structure. Many of the risks involved in concrete demolition are present during demolition work. Moreover, concrete demolition activity is especially perilous because it involves additional risks as a result of incomprehensible elements
Primarily, the workers will use excavators or concrete demolition hammers to pull down interior walls, buildings, construction, ore bin of mining closure, and so on. Nevertheless, due to particular areas, the harness of buildings, and the construction of concrete, using those tools and equipment would be challenging for operators. By this, utilizing a stronger flame generated by thermic lance steel pipes would be an accurate choice to solve the situation.
Ore bin of Mining Closure
Thermic Lance for Demolition Works
Thermic Lance is an oxygen lance steel pipe filled with wires or a mixture of wires and an inner pipe, producing flame up to 4,000℃ by blowing oxygen, with various applications as below:
- Opening tap hole and iron notch of Blast furnace and Electric Furnace.
- Eliminating metal and slag stuck to mixer car, converter, and Electric Furnace.
- Cleaning tundish nozzle and ladle nozzle in continuous casting equipment.
- Fusing and cutting steel pipes and large scrap objects.
For Demolition purpose:
- Types of pipes for concrete demolition of high-rise buildings, ore bin of mining closure
- Thermic lance 17.3 Type-W is suitable for thicker and harder areas.
- Safety use Thermic Lance
The standing of the operator should be higher than the cutting point so that the thermic lance makes an angle of around 45 degrees. Oxygen pressure should be regulated at about 9 bar for seamless cutting.
Position of the operator cutting Concrete by Thermic Lances.
Protective equipment
The operator must wear protective gear to shield from the particle projection and sparks
Performance of Thermic Lance for Concrete Demolition
The test has been performed with 2 sizes of thermic lance OD17.3 and OD16.0 for both Type-W and Type-T. The test result shows that Type-W is more suitable for concrete cutting than Type-T of the same pipe size. And our recommendation is to use Thermic lance OD17.3 which performs better than OD16.0.
Structure of concrete with steel bar inside
The steel bars are put inside together with concrete demolition for the testing operation of Thermic Lance and the below shows how it performs during our internal test.
Whole Concrete with steel bar inside before cutting by Thermic Lance
Whole Concrete with steel bar inside after cutting by Thermic Lance
The testing result shows that the pipe consumption speed at 10.4 (mm/sec), the cutting ability for 1 meter of pipe is 8300 mm2, and the cut
speed rate at 86 mm2. Therefore, we recommend the Thermic Lance OD 17.3 Type W for concrete demolition, especially for the mining industry.
Conclusion
Working for concrete demolition and demolishing portions of mining closure is a risky task, and thermic lance-using construction enterprises are uninformed of what to look for to ensure safety. There is a lack of information regarding the usage of thermic lances to cut hardened concrete structures. It is ideal for consumers to be able to find a way for having steel structures and concrete destruction that is well regarded for safety and security for old high-rise buildings that cannot be demolished by excavators owing to a shortage of room.
If you wish to know more about our solution for concrete demolition, especially for the Mining industry, please contact our team to support you during your journey.
To know more about our various products, please feel free to contact us at sales@daiwaanayasteel.com.
Daiwa Anaya Steel Private Limited is a part of Anaya Steel, LLC (US parent company). Our company has over 30 years of involvement in steel products. It mostly deals in:
- Specialized steel hardware – punched, pressed, galvanized, powder coated.
- Steel pipes and tubing – specialized, color coated, galvanized and structural.
- Our lance pipes are manufactured by Daiwa Lance International (DLI) in Vietnam.
