Refinery Service Research Articles

Reducing the Risk of High Temperature Creep Failures in Refinery Service Component and Equipment

Abstract This paper highlights about the high temperature creep failures affecting refinery materials, structures, and components for which good operational practices, proper maintenance, and inspection are required to avoid major failures and to maintain safety of personnel and integrity of static equipment and to avoid unplanned shut down.

Modeling and Stress Analysis of Pump Piping

Every process piping industry uses several pumps in each process unit. Sometimes the analysis is very critical. This article explains about elaborate the method followed for stress analysis of a pump piping system. The stress system consists of typical discharge and suction lines of two pumps. Fluid from the tank is pumped to another. As per P&ID only one pump will operate at a time, other pump will be a stand by pump. This article explains about the stress analysis methodology in three parts: - a) Modeling of Pump b) Preparation of analysis Load cases and c) analyzing the output results. External loads imposed by piping on rotating equipment nozzle should be less than allowed loads. If excessive loads are imposed, misalignment may result that affects mechanical operation and could cause objectionable vibration. A close alignment between rotating and stationary parts must be maintained. The provision for expansion of the casing and maintaining close clearances requires that the forces and moments due to the piping are limited. The API 610 standard gives equation to calculate allowable forces and moments in the case of pumps for general refinery service. The criteria apply for pumps with 4 Inches discharge nozzles or smaller (suction nozzle may be larger) and situations where the pump is constructed of steel or alloy steel. The modulus of elasticity of the piping material at operating temperature (known as hot modulus) can be used to calculate actual loads. Using hot modulus will result in lower loads because the piping is more flexible at higher temperature. This paper is designed for studying a wide range of abilities and backgrounds this will cover the fundamental principles, concepts used in pipe stress analysis.

Alkaline Carbonate SCC Failures at a Refinery

A metallurgical evaluation was performed to investigate two failures from carbonate-containing sour water service at a refinery. The failure mechanism for both fractured components (a pipe and a heat exchanger tube) was alkaline carbonate stress corrosion cracking. Alkaline carbonate stress corrosion cracking is a mechanism that has become more widely recognized in refinery service. This paper details the visual, SEM/EDS, metallographic, and microhardness evaluations used to determine the failure mechanism for each refinery component.

Improvement of refinery maintenance and mechanical services: application of lean manufacturing principles

Purpose: The aim of this paper is to show a successful improvement in operations with the implementation of lean manufacturing strategies in a Caribbean oil and gas company. Design/Methodology: Initially, a review of literature was performed on lean manufacturing (LM) tools. Then interviews and GEMBA walkthrough was carried out in the selected case organisation followed by the problems faced were analysed using value stream map (VSM) together with root cause analysis tools. At the end, future state VSM was developed and the benefits due to implementation of LM principles were quantified. Findings: The study revealed that a traditional approach is currently being used on the shop floor thus increasing the opportunity for hidden wastes between the processes as well as increased repair time due to defective equipment. The results concluded that improved shop floor utilisation, reduction in preparation time and hidden wastes were identified on the shop floor. Originality/value: The review of literature indicated that implementation of the lean principles in the Caribbean oil and gas sector has not been explored. Further, the study results provide a road map for similar organisations to achieve operational improvement but also is valuable for academic and research community for practical implementation of lean principles.

Standards for fired heater design: Analysis of two dominant heat flux variation factors

Many fired heaters in all parts of the globe are designed according to long-standing standards of the American Petroleum Institute. The relevant API standard 560 is to a large degree based on heat flux non-uniformity factors that have been first graphed early in the 20th century using idealised 2D calculations of radiative heat transfer. The basic set of assumptions and values for these factors has recently been challenged, as they neglect or underestimate several significant aspects of nonuniformity including longitudinal heat flux variation due to up-to-date low-NOx burners, interaction of flames from multiple burners, Coandă effect and non-ideal geometry.This paper brings new data and quantified corrections of two dominant heat flux variation factors (tube circumferential factor and longitudinal factor) that are based on numerical modelling, large-scale laboratory measurements and real-life data from operating fired heater. The new information provides evidence that standardised design calculations of fired heaters for refinery service need urgent update and revision, mainly concerning the longitudinal factor. The results show that real-life heat flux distribution can be significantly less uniform than estimated by traditional design techniques (such as API Design Standards).

Economic and Ecological Evaluation of Land Use Change: Evidence from Karelia

Land use change and a shift in economic activity often bring to unpredictable consequences for local ecosystems. There is a necessity of making preliminary evaluation and analysis of comparing the different types of economic and ecological transformation, including cost and benefit analysis, not only for business and local population, but for the whole environment. We give an example of a particular animal husbandry farm in Karelia and show how potential change in economic specialization can be effective on a 10 years horizon. Among other land use types, we chose peat mining and wetland conservation. Each type of activities was complexly evaluated with different types of costs and benefits. In the paper, we use a method of land use change evaluation including the value of ecosystem services. The monetary values of ecosystem services are given with the respect to foreign analogues and taking into account local realities and prices. Our results have shown that the most beneficial for the society and the environment is wetland conservation, due to their berries picking service, which are highly appreciated on the market, and due to low costs for the third parties, since wetlands contain regulative and refinery services for local ecosystems. As a contrary peat mining is a profitable business, but pollutes the environment because of carbon emissions into the atmosphere. The current specialization for animal husbandry is neither an optimal solution because of low profitability of the chosen farm. The results of the research can be used for optimization in regional politics in the sphere of agriculture and environment economics in order to protect the ecological balance between human activities and nature.

Carburization behavior of high velocity oxy fuel sprayed metallic coatings at 900°C

Purpose– The purpose of this investigation was to evaluate the performance of high velocity oxy fuel (HVOF) coated SS-310 samples in a carburizing environment.Design/methodology/approach– The carburization behavior of metallic coatings with three different compositions was studied under isothermal carburizing exposure conditions at 900°C for 125 hours. The coatings were deposited on SS 310 substrates using the HVOF technique. The ASTM Standard method was used to evaluate coating adhesion. Scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, X-ray diffraction and weight gain were used to evaluate the surface morphology, microchemical composition, phase constitution and degree of environmental protection imparted by the coatings.Findings– The experimental results indicate that Ni-rich coating offered better protection to SS 310 alloy compared to Co-rich coatings in carburizing environments. This was thought to be due to the formation of a continuous protective layer of Cr2O3on the Ni-rich coating surface.Originality/value– The study has direct practical relevance to the petrochemical industry, particularly for refinery applications. In refinery service, SS310 is used in header damper plates. The useful service life of such header plates can be extended by the use of high temperature corrosion resistant metallic coatings. The present investigation highlighted the protection offered by Ni-based HVOF coated SS-310 samples in carburizing environment.

Explosion and fire in a gas‐oil fixed roof storage tank: Case study and lessons learned

AbstractOn November 2, 1997, a fixed roof gas‐oil tank located in the tank farm of Ashdod Oil Refinery exploded, causing the death of one Sample Man, and a fire in two adjacent tanks located in the same dike. The fire lasted less than 3 hours, but there was significant public concern about the necessity for emergency evacuation from two neighboring settlements.Emergency operations of the refinery and outside services were very effective, and fires in both tanks and the dike were put out without any additional damage to other equipment in the tank farm. The source fire was classified as a heavy top phase pool fire.The investigation pointed out that hydrogen was the source of the explosive mixture in the tank. Hydrogen penetrated the tank as a result of non‐complete gas‐oil stripping at the exit of a hydro treating unit. The source of ignition was an electrostatic spark initiated by synthetic rope (instead of a cotton one) used with a device to obtain samples from the tank.After the accident, it was found that a similar scenario was reported about 15 years earlier. However, it was not disseminated widely enough through accident databases.

The effect of elevated temperature refinery service on the chemistry of M23C6 carbides in 9Cr-1Mo steel

en

Bellows seal takes on refinery services

Bellows seal takes on refinery services

Development of an 11000-r/min 3500-HP induction motor and adjustable-speed drive for refinery service

Faced with the need to revise the refining process to produce reformulated gasoline in compliance with state and federal clean air requirements, the Chevron El Segundo Refinery found justification to purchase special high-speed electric motors with adjustable-speed drives to replace existing steam turbine recycle compressor drivers. This paper explains the decision-making process and rationale that led to this purchase. Further, it describes the design/development process and testing/approval procedures to demonstrate the necessary reliability levels for critical refinery service in this first-of-its-kind application.

CROLOY 800

Abstract CROLOY 800 is an austenitic stainless steel intended for high-temperature service. In addition to its excellent resistance to corrosion in various media, it exhibits excellent strength and resistance to oxidation at elevated temperatures. Among its many applications are high-temperature processing of hydrocarbons in refinery or petrochemical services, superheater and reheater tubin8g, nuclear reactor steam generators, heat-treating equipment and food processing. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as creep. It also includes information on corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: SS-454. Producer or source: Babcock & Wilcox Company.

Experience With Piston and Piston-Rod Seals for High-Pressure Reciprocating Compressors Injecting Natural Gas on North Sea Production Platforms

Summary The need to restrict flaring of associated natural gas has emphasized the importance of reliability of high-pressure reinjection compressors installed on certain North Sea platforms. This paper reviews the contribution made by the development of piston and rod seals used on injection compressors, with reference to three important fields: Beryl, Statfjord, and Thistle. Early North Sea Reinjection Experience During 1977 the first associated natural gas was reinjected in the U.K. oil sector. This operation is performed by two-stage reciprocating compressors. Early experience with these compressors revealed that the piston and rod seals. which are subjected to pressures approaching 400 bar [40 MPa], were a major source of machine failures. These failures consisted of severe scuffing and wear between the bronze sealing elements (piston and packing rings) and the countersurface (liners and piston rods), causing erratic seal life, sometimes of only a few hours' duration, together with badly damaged liners and piston rods. The typical condition of used bronze piston rings is illustrated in Fig. 1, and the operating lives achieved with bronze seals are summarized in Table 1. The most serious consequence of this unreliability was its effect on continuity of oil production, and an immediate development program to eliminate such failures was begun by the platform operator in collaboration with the appointed seal manufacturer. Details of this development are presented, including an analysis of the causes of seal failures and measures taken to remedy them, with particular attention to seal material and design and to lubrication requirements. Field experience gained in the application of the modified seals is summarized in three case histories. details of which arc given in Tables 2 through 4, with comparative results listed in Table 5. Selection of Seal Material At the outset of this development program, a change to nonmetallic seal materials for both the piston rings and the rod packings was considered on the basis of a proprietary grade of filled polytetrafluoroethylene (PTFE), which had already been used successfully for packings and piston rings in various lubricated compressor installations, includingethylene primary compression to 350 bar [35 MPa],ammonia synthesis gas compression to 350 bar [35 MPa], andhydrogen compression in refinery service to 200 bar [20 MPa]. JPT P. 2294^

ACI TYPE HA

Abstract Type HA is an air-hardening iron-chromium-molybdenum alloy containing sufficient chromium to provide good resistance to oxidation at temperatures up to about 1200 F. Castings of type HA alloy are used widely in oil refinery service and in the glass industry. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness and creep. It also includes information on high temperature performance and corrosion resistance as well as casting, heat treating, machining, and joining. Filing Code: SS-301. Producer or source: Stainless steel foundries.

石油精製用プロセスポンプの動向(水力機械小特集)

石油精製用プロセスポンプの動向(水力機械小特集)

CUPRO NICKEL 30%-716

Abstract Cupro Nickel, 30%-716 is a high strength copper-nickel-iron alloy for heat exchanger tubes in power plant feed water heaters, and also for oil refinery service. This datasheet provides information on composition, physical properties, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, joining, and surface treatment. Filing Code: Cu-200. Producer or source: Anaconda American Brass Company.

Sulfuric Corrosion of Chromel-Alumel Thermocouples

Abstract An investigation of premature, catastrophic failures of Chromel-Alumel thermocouples in petroleum refinery service disclosed that failures consisted of intergranular fractures of the Alumel wires caused by sulfidic corrosion. This type of failure was observed in the laboratory to occur in the 649–816 C (1200–1500 F) temperature range and in me presence of sulfides. Sulfur was detected by electron microprobe x-ray analysis in grain boundaries and cracks in failed Alumel wires. Intergranular sulfidic attack also was observed in progress by means of hot-stage metallography. A mechanism for the observed type of attack is proposed: At temperatures in the 649 C (1200 F) range, sulfur diffuses into grain boundaries of Alumel and forms the nickel sulfide, Ni3S2±x and the eutectic, Ni-Ni3S2±x. Liquefaction of the eutectic above 645 C (1193 F) produces grain separations and wire failure. Above 810 C (1490 F), however, Ni3S2±x is unstable, hence, in this range Alumel corrosion is not limited to grain boundaries only and catastrophic failures do not occur. The proposed corrosion mechanism may be applicable to other corrosion problems involving nickel and high-nickel alloys.

石油精製および石油化学設備の高温腐食

石油精製および石油化学設備の高温腐食

High Temperature Corrosion in Refinery And Petrochemical Service

Abstract The paper is concerned with the corrosion phenomena likely to influence the selection of materials for refinery service at elevated temperatures. The problems of oxidation, sulfidation and carburization are discussed in detail and consideration is given to the effects of condensate corrosion and residual oil ash corrosion. The contributions of various alloying elements in the common engineering alloys to their physical and mechanical behavior as well as to their corrosion resistance at elevated temperatures are discussed. Basic considerations for the selection of suitable alloys to withstand high temperature corrosive environments are outlined. 8.4.3

Studies on the Volute Pump Handling Viscous Fluids : 1st Report, Oil-Pumping Characteristics

Recently there has been a manifold increase in the demand for volute pump for the oilfield and oil refinery services. It is suggested that the properties of viscous fluid influence the hydraulic performance of a centrifugal pump as compared with action of water, and already a few have been rported as for its influence. It seems, however, that there remain many problems unsettled as to the pumping behavior of volute pump handling viscous fluids. The writers measured the hydrodynamic performance characteristics of 75 mm volute pump handling various viscous fluids in order to analyze the characteristics. In this paper they lead the expressing method of whole properties under various conditions and show the performance characteristic diagrams indicating the indluence of viscosity.