material properties of metal that extensively used in oil and gas facility

In general, the materials used in oil and gas facilities are classified into 3 basic groups: metals, ceramics, and polymers. This scheme is primarily based on the chemical makeup and atomic structure. However, metallic materials are the most widely used group.   Metal for example, carbon steel, Alloy (stainless steel etc), aluminum, copper, titanium, and nickel. Atoms in metals and alloys are arranged in a very regular and relatively dense manner. With regard to mechanical characteristics, these materials are relatively stiff and strong, but ductile (ie, capable of large deformations without fracture), and are resistant to fracture. Material properties of metal that usually considered :   yield strength ultimate strength allowable stress at elevated temperature strain modulus of elasticity hardness toughness poison ratio coefficient of expansion   Performance of material depends on its properties, which in turn is a function of its structure; Furthermore, the structure is determined by how the material has been processed. The facility engineer used the properties to make design calculation for equipment. Allowable stress at elevated temperature is used to determine the equipment thickness. Below is example of pipeline thickness requirement as per ASME B31.3. The lower the allowable stress (S), the higher thickness required[…]

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what is the best material used in oil and gas facility

do we need the best material at any cost? In the oil and gas industry from upstream to downstream using various types of metal materials. This material is used for operating temperature – 40 oC to 1,000 oC. How do we choose the best materials for oil and gas facilities? Facility engineers are often confronted with conditions to choose the best type of material. In general, there are 3 main criteria that are often used. 1. best material for possible operating conditions. These operating conditions will largely determine the required material properties. For example, we will use pressure vessel on operating conditions at high pressure and temperature, then we will need material that has high strength property and holds at high temperature. There is only a rare chance that a material has a maximum or ideal property combination. So, it may be necessary to trade off one property to gain another property advantage. Classic examples involve strength and ductility. usually, the material that has high strength will only have limited ductility. In such cases, a reasonable compromise between two or more properties may be required. 2. material property damage that may occur during operation. Property of material is not always[…]

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what is wet corrosion in oil and gas industry?

wet corrosion There are many ways to classify corrosion. However, in general, corrosion is divided into 3 major groups namely Wet corrosion, Dry corrosion, and biological corrosion. Wet corrosion, as the name implies, occurs only in the presence of an aqueous solution or an electrolyte. Dry corrosion or dry corrosion occurs when there is no fluid present or temperature above the dew point of the environment. Biological corrosion or biological corrosion is a specific type of wet corrosion that occurs in the presence of living organisms. sometimes wet corrosion is named as aqueous corrosion. Wet corrosion is an electrochemical process, and electrochemical reactions are used to explain it. Wet corrosion, as the name implies, occurs only in the presence of an aqueous solution (including condensation of moisture) or electrolyte and is the most common type of corrosion. Wet corrosion can be further categorized by the appearance of rusty metals : a. Uniform Corrosion b. Galvanic Corrosion c. Crevice Corrosion d. Pitting e. Intergranular Corrosion f. Selective Dealloying g. Erosion corrosion h. Stress Corrosion Cracking (SCC) Metals corrode through simultaneous oxidation and reduction reactions. The oxidation reaction generates electrons and places the ions in the solution. This reaction occurs at the[…]

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What is the best practice of corrosion monitoring ?

why we need to conduct corrosion monitoring? Corrosion monitoring is an activity to check corrosion happened in an equipment. before we conduct a corrosion monitoring, we must understand the basic of corrosion and corrosion type. Corrosion is the destruction or degradation of a metal due to a redox reaction between a metal and various substances in the environment that produce undesirable compounds. The most common example of corrosion is iron corrosion. In the event of corrosion, the metal undergoes oxidation, while oxygen (air) is reduced. The metal rust is generally an oxide or carbonate. The chemical rust formula is Fe2O3.nH2O, a solid brown-red substance. Corrosion is an electrochemical process. it means we must understand an electrical side and chemical side. In iron corrosion, certain parts of the iron act as the anode, in which iron oxidizes. Fe(s) <–> Fe2+(aq) + 2e The freed electrons in the anode flow to another part of the iron acting as a cathode, in which the oxygen is reduced. O2(g) + 4H+(aq) + 4e <–> 2H2O(l) or O2(g) + 2H2O(l) + 4e <–> 4OH–(aq) The iron ions (II) formed at the anode subsequently oxidized to form iron (III) ions which then form the hydrated oxide compound,[…]

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