January 8, 2019

How is the theoretical weight of spiral steel pipe calculated?

  The theoretical weight of steels is obtained by calculating nominal dimensions and density (which is called specific weight in the past). This is directly related with the steel length, the cross section area, and the allowable size deviation. Because of the allowable deviation in the process of manufacturing, the calculated theoretical weight is somehow different from the actual value, and the theoretical value is only for reference while estimating. The fundamental equation is as follows: Steel pipe single meter weight calculation (kg / m): W = (outer diameter – wall thickness) * wall thickness * 0.02466 = 2408 * 12 * 0.02466 […]
January 7, 2019

Corrosion Resistance of API 5L Pipeline Steel with Coating Protection

ABSTRACT The corrosion resistances of enamel-coated steel pipe in  3.5 wt% NaCl solution was evaluated and compared with those of epoxy-coated pipe using open-circuit potential, linear po- larization resistance, and electrochemical impedance spectros- copy tests. T-001c enamel slurry and GP2118 enamel powder were sprayed to steel pipe in wet and electrostatic processes, respectively. The phase composition and microstructures of the two enamels were characterized with x-ray diffraction and scanning electron microscopy (SEM). The surface roughness of enamels and their bond strength with steel substrates were quantified to understand coating quality. SEM images revealed that both types of enamel coatings have […]
January 4, 2019

Casing pipe application in high-temperature gas wells

In recent years, with the decreasing number of easily exploitable oil and gas wells, it has become necessary for oil and gas wells to go deeper on both underground and underwater. And, tubing and casing strings are subjected to higher temperature and higher pressure in these wells, which would probably cause casing failure or gas leakage in the high-pressure/high-temperature (HPHT) wells. Hence, more attention has been paid to wellbore integrity in oil and gas industry in recent years.1,2 The key factor of wellbore integrity is casing string connections, which are expected to provide both structural and leakage integrity under severe environment. […]
January 4, 2019

Properties of Galvanized Steel Pipe Welds

Properties of Galvanized Steel Pipe Welds Galvanizing has been used to protect iron and steel from rusting for over a hundred years in places as diverse as the wire rope used for the suspension cables on the Brooklyn Bridge to gutters on houses. Galvanizing is simply coating of zinc over steel. Like paint, galvanizing protects steel from rusting by forming a barrier between the steel and the environment, but galvanizing goes one giant step further than paint — it also provides electrochemical protection of the steel. Since zinc is electrochemically more reactive than steel, it oxidizes to protect the steel […]
January 2, 2019

Why not galvanizing after welding for steel pipe

Why not galvanizing after welding Why not avoid the whole problem of welding galvanized steel pipe sheets after galvanizing? After all, steel products are always galvanized after manufacture, because there has been no practical way to restore the galvanizing effect after welding. Zinc plating after manufacture is still conventional, but must be done with great care. The manufacturing must be cleaned in acid, the acid must be neutralized, and then made into a liquid zinc can that must be immersed in excess of 900 °F. People must be very careful to make it dry when it is put into zinc, […]
December 26, 2018

A333 Grade 6 Low Carbon Steel in Pipelines – Microstructural Characterization and Hardness Properties

M. N. Ervina Efzan*, S. Kesahvanveraragu, J. Emerson   1.0 INTRODUCTION 1.1 Offshore Pipeline Material Pipelines in offshore platform are made up of various types of materials. Selection of material relies upon certain considerations such as cost, functional requirement, operating conditions of pressure and temperature, corrosion rate and so forth [1-2]. Since there are varieties of pipelines in offshore platform, material selection and those considerations are highly required. In offshore industry, metal is the highly used material that can be assorted into ferrous and non-ferrous metals [1-3]. Metals containing iron (Fe) as their premier composition are known as ferrous metals, whereas metals containing other elements are termed as non-ferrous […]
December 12, 2018

Pipe Manufacturing Process

The Manufacturing Process of Seamless Pipe and Welded Pipe Seamless Pipe Manufacturing Process Seamless pipe is strongest amongst all pipes type as it has a homogeneous structure throughout pipe length. Seamless pipes are manufactured in a verity of size and schedule. However, there is a restriction on the manufacturing of large diameter pipe. Seamless pipes are widely used in the manufacturing of pipe fittings such as bends, elbows, and tees.   Mandrel Mill Process In Mandrel Mill pipe manufacturing process, steel billet is heated to high temperature in the rotary furnace. A cylindrical hollow, which is also known as mother hollow, is produced with the help […]
December 5, 2018

Asia’s steel trade faces multiple challenges

Weak domestic demand and trade friction are important challenges that the development of the steel industry faces at present, and the abuse of trade protection measures is bringing about adverse impacts in many aspects. For the development of China’s steel market, Xia Xiaokun, who is vice president of Shanghai Mysteel Research Institute. He said, this year, the environmental restricting output normalized steel production fell year-on-year, then the strong toughness of China’s Economic ensure the smooth running of domestic steel consumption. And the whole of China’s iron and steel spot market prices is running at a high state, while the profits […]