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What are the applications of square tubes in the energy industry

Source:m.brill-sh.com.cn      Release date: 2025-07-21
Information summary:Square tube (steel pipe or alloy pipe with square cross-section) is widely used in exploration, mining, transportation, storage, and equipment manufacturing in the energy industry due to its high structural strength, good stability, high space utilization, and strong corrosion resistance (some materials). The specific scenarios are as follows:
       Square tube (steel pipe or alloy pipe with square cross-section) is widely used in exploration, mining, transportation, storage, and equipment manufacturing in the energy industry due to its high structural strength, good stability, high space utilization, and strong corrosion resistance (some materials). The specific scenarios are as follows:
1、 Oil and gas extraction and transportation field
      The oil and gas industry is one of the core application scenarios for square tubes, especially playing a key role in surface equipment, pipeline support, and downhole tools:
Drilling platform and oil production equipment structural components
      The frame structure of offshore or onshore drilling platforms (such as platform columns, operation platform supports, equipment bases) needs to withstand extreme loads (wind, wave impact, equipment self weight), and square tubes are often used as load-bearing skeletons due to their superior torsional resistance compared to circular tubes. For example, high-strength low-alloy square tubes (such as Q355B) are used to build platform guardrails and drilling rig base support legs, which are welded or bolted together to form a stable frame that balances lightweight and deformation resistance.
      The valve bracket on the Christmas tree and the auxiliary support of the crank connecting rod of the pumping unit are also commonly made of small-sized square tubes (with a side length of 50-150mm), which are easy to install and fix, and save space.
Oil and gas pipeline auxiliary facilities
      In the supporting facilities along long-distance oil and gas pipelines (such as the West East Gas Pipeline Project), square pipes are used for:
      Pipeline support: In the overhead pipeline section crossing rivers and highways, square tubes are used as support beams or columns to support the weight of the pipeline and resist lateral wind force, avoiding deformation of the pipeline due to vibration or settlement;
      Cathodic protection device framework: To prevent pipeline corrosion, sacrificial anodes or external current devices need to be installed along the line. Square tubes are used to build the equipment protection framework to protect the device from external collisions;
      Equipment framework of oil pumping station: The fixed brackets for pump bodies, filters, measuring instruments and other equipment in the station are welded with square tubes to facilitate the integration of pipeline and cable layout.
Underground tools and wellhead equipment
      The telescopic arm components of some downhole salvage tools and well repair equipment are made of high-strength alloy square tubes (such as 27SiMn), which utilize their good rigidity and resistance to bending to transmit torque or thrust in high-pressure downhole environments; The base of the wellhead device's blowout preventer and the support frame of the throttling manifold are also commonly reinforced with thick walled square tubes (wall thickness 10-30mm) to enhance overall stability.
2、 Power industry (generation, transmission, and energy storage)
      In the power system, square tubes are mainly used for equipment structural support, cable protection, and energy storage facility framework:
      Structural components of power generation equipment
      Thermal power plants: auxiliary supports for boiler steel frames, crossbeams for turbine bases, conveyor belt supports for coal conveying systems, etc. are constructed with square tubes to support the load-bearing structure. Especially in high-temperature environments (such as near boilers), heat-resistant steel square tubes (such as 12Cr1MoV) are selected to resist deformation caused by thermal expansion and contraction;
       Wind power generation: The internal platform support of the wind turbine tower and the fixed frame of the equipment in the engine room (such as the generator base support) are made of anti-corrosion treated square pipes (such as galvanized square pipes), which are suitable for outdoor humid and windy environments and reduce corrosion;
       Solar power station: The beams and columns of the photovoltaic brackets are made of aluminum alloy square tubes or galvanized steel square tubes, and the cross-sectional design is conducive to fixing the tilt angle of the photovoltaic panels, while saving installation space and improving land use efficiency.
Transmission and distribution facilities
       Substation architecture: The equipment brackets (such as support columns for circuit breakers and isolating switches) and cable tray frames of high-voltage substations are commonly welded with square tubes, which are simpler and have better resistance to lateral forces (such as typhoons) compared to angle steel frames;
       Cable protection tube: When laying some outdoor cables, square tubes are used as protective shells (with insulated cables inside), especially in areas where multiple cables run parallel (such as power plant areas). The square cross-section of the square tube is easy to arrange, reducing space occupation and preventing damage to the cables from external collisions.
Energy storage equipment framework
       The shell frame of large energy storage power stations (such as lithium battery storage cabinets and auxiliary equipment for pumped storage power stations) adopts lightweight alloy square tubes (such as aluminum magnesium alloy square tubes), which not only meets the structural strength requirements, but also reduces the overall weight and facilitates modular assembly; The internal support grid of the energy storage battery pack is also commonly separated by small-sized square tubes to improve heat dissipation efficiency.
3、 In the field of new energy (photovoltaic, wind power, hydrogen energy)
      The new energy industry has higher requirements for equipment lightweight and weather resistance, and the application of square tubes focuses more on customization and material adaptation:
Photovoltaic power station bracket system
      The brackets for ground or roof photovoltaic arrays are widely made of aluminum alloy square tubes or high-strength galvanized steel square tubes:
      Aluminum alloy square tube is lightweight and corrosion-resistant, suitable for rooftop photovoltaics (reducing building load-bearing pressure);
      Galvanized steel square tube has lower cost and higher strength, suitable for large-scale photovoltaic power stations on the ground. It can be quickly assembled through bolt connections and can withstand loads such as snow and hail.
Auxiliary structure of wind power equipment
      The transportation bracket for wind turbine blades and the maintenance platform frame at the bottom of the tower are made of thick walled square tubes (such as Q460 steel square tubes) to ensure that the blades do not deform during transportation and are easy for maintenance personnel to stand and operate; The collection line towers of wind farms are partially constructed with square tube composite structures, replacing traditional cement poles and shortening the construction period.
Hydrogen energy and energy storage equipment
       In the hydrogen energy industry chain, the frame of electrolytic cell equipment and the support base of hydrogen storage tanks are made of stainless steel square tubes (such as 316L) to resist corrosion in hydrogen environments; The stack support frame of the flow battery energy storage system is constructed with a multi-layer structure using square tubes to improve space utilization and facilitate the layout of electrolyte pipelines.
4、 Coal and mining energy sector
      During coal mining and processing, square tubes are used for equipment structure and conveying systems
Mining machinery and equipment
      The frame of the coal mining machine and the side support of the scraper conveyor are made of high-strength wear-resistant square tubes (such as 20CrMnTi alloy square tubes) to resist the impact and wear during coal seam mining; The shell frame of underground explosion-proof equipment (such as ventilation fans and water pumps) is welded with thick walled square tubes, which have both compressive and explosion-proof functions.
Coal transportation and processing facilities
      The bracket of the coal conveyor belt and the equipment platform of the coal washing plant (such as the support structure of the jigs and filters) are constructed with square tubes for easy installation of protective barriers and maintenance channels; The discharge port frame of the coal bunker is reinforced with square tubes to prevent deformation of the silo wall caused by coal accumulation.
5、 Nuclear energy field
      The nuclear energy industry has strict requirements for material safety and radiation resistance, and square tubes are mainly used for auxiliary equipment structures
Nuclear power plant auxiliary facilities
      The safety shell support and the base frame of the circulating water pump around the nuclear reactor are made of low-alloy steel square tubes (such as 16MnDR), which have been quenched and tempered to have low temperature resistance and fatigue resistance; The pipeline support grid in the nuclear power plant is welded with square tubes to form a grid structure, fixing steam pipelines and cooling water pipes to avoid leakage at the connection caused by vibration.
Nuclear waste treatment equipment
      The transportation bracket for nuclear waste storage tanks is made of steel square tubes coated with lead alloy, which not only meets the load-bearing requirements but also shields radiation through a lead layer to ensure transportation safety.
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