University of Birmingham has recently acquired a low pressure boiler for its energy research and teaching laboratories. The boiler is made from seamless steel pipes, in accordance with the GB3087-1999 standard. The purpose of this article is to provide an overview of the properties of the seamless steel pipes and how they are used for low pressure boilers.
The seamless steel pipes used for low pressure boiler applications are produced from several traditional types of steel. These include carbon steel, low alloy and stainless steel. Carbon steel is the most common type of steel used for low pressure boilers, as it is cheaper and easier to work with than the other materials. Low alloy and stainless steel are preferred for high temperature applications, due to their greater resistance to corrosion and better thermal stability.
The pipes used for low pressure boiler applications must meet certain criteria. Generally, they should have a smooth internal surface, with a minimum wall thickness that is suitable for the intended application. Steel pipes are usually produced to order, according to customer specifications.
The most important property of seamless steel pipes used in low pressure boilers is the tensile strength. This is the maximum amount of force that the pipes can resist before being deformed or broken. The ultimate tensile strength of the seamless steel pipes must be at least two times greater than the maximum pressure that the boiler will need to operate at. This ensures that the steel pipes will be strong enough to contain the steam pressure generated by the boiler.
Another important property to consider is the impact resistance of the steel pipes. This is the ability of the metal to withstand impacts, such as those caused by the sudden release of pressure or the formation of bubbles in the steam released. The metal should have a minimum impact resistance of 15 times the maximum operating pressure of the boiler.
The strength of seamless steel pipes used for low pressure boiler applications is also affected by the thermal expansion coefficient. This is the amount by which the metal expands or contracts when subject to changes in temperature. A higher coefficient of thermal expansion is desirable, as it will reduce the effects of thermal stress on the metal, increasing the life of the boiler.
Finally, the corrosion resistance of the metal should also be taken into consideration. Low pressure boilers operate in humid environments and can quickly corrode if not properly protected. A low corrosion resistance will reduce the life of the boiler and increase the cost of replacement parts.
In summary, seamless steel pipes are used for low pressure boilers due to their high strength and impact resistance, as well as their ability to resist corrosion. To ensure the pipes last as long as possible, it is important to select ones with a minimum wall thickness and low thermal expansion coefficient, as well as good corrosion resistance.
