Novel Elastomer Materials for Extreme Temperature Operation in Subsea Thermal Insulation Applications at Unlimited Water Depth

2021 ◽  
Author(s):  
Adam Jackson ◽  
Rodrigo Diaz ◽  
Heidi Svalund ◽  
Raymond Hansen ◽  
Grethe Hartviksen
Keyword(s):  
High Temperature ◽  
Thermal Insulation ◽  
Water Depth ◽  
Extreme Temperature ◽  
Base Material ◽  
Development Project ◽  
Pressure Vessels ◽  
Hand Tools ◽  
Gentle Pressure ◽  
Cost Efficient

Abstract Rubber based systems have been used in subsea thermal insulation for many years and have proven themselves to be reliable and cost efficient. Formulations have been changed over the years, pressing the maximum usage temperature upwards and into the realm of 160 to180°C in a hot-wet environment. Until recently there was a need for high temperature along with pressure vessels (autoclaves) for vulcanisation. This has limited the widespread use of such systems. Recent changes have eliminated the need for autoclaves, however the high temperature vulcanisation hasstill been required. A novel formulation has been developed to address these shortcomings, so that this class of materials could have wider use. This new material employs freely available materials in a unique blend. The material contains no hydrolysable groups and can operate from −40°C to 180°C continuously in air and in a hot-wet environment and retains its resilience and flexibility; and thus opening for use in both high and low temperature systems. The formulation does not include the use of hollow glass microspheres and is, correspondingly, without water depth limitations. A new, highly reliable vulcanisation chemistry allows for a stable latency time for application, with vulcanisation temperatures reduced to 50°C. This allows for rapid hand application and simultaneous vulcanisation on subsea trees, valves, manifolds, etc. The material is self-agglomerating, merging under gentle pressure, and can be applied at high thickness. As the base material has an intrinsically low thermal conductivity, glass-based fillers are not needed. The material adheres well to painted or primed surfaces and to many other materials typically used in the offshore thermal insulation industry. The 2-component material is conveniently combined on site, reducing the need for refrigeration during transport and easing mobilisation logistics and is applied using simple hand tools. Extruded profiles can be used directly on complex structures or combined into sheets for ease of application on more regular shapes in order to optimise application rates. Moulds are not required for application, reducing engineering and fabrication cost, while also shortening mobilisation time. The system has been extensively qualified according to ISO 12736 for continuous use at 180°C. This paper will detail important aspects of the development project along with the results of the qualification testing.

Manufacture of Advanced 2.25Cr-1Mo-V Pressure Vessel Steel for High Pressure and High Temperature Hydrogen Service

2004 ◽  
Author(s):  
T. Hasegawa ◽  
A. Narita ◽  
H. Iga ◽  
S. Inoue
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Pressure Vessel ◽  
Base Material ◽  
Postweld Heat Treatment ◽  
Pressure Vessels ◽  
Pressure Vessel Steel ◽  
Vessel Steel ◽  
Manufacturing Technologies ◽  
Welding Consumables

At this moment, the materials which are applied for high pressure and high temperature services are selected from conventional 2.25Cr-1Mo, 3Cr-1Mo-V and 2.25Cr-1Mo-V steels. Especially, the application of 2.25Cr-1Mo-V steel is increased extremely rather than the other steels in order to take the advantage of higher strength and better resistance to hydrogen damages such as hydrogen attack, hydrogen assisted crack growth and also hydrogen induced disbonding. In order to achieve these properties, the vanadium element is added intentionally into base material and welding consumables. Due to the addition of vanadium, the engineer have recognized that there is some possibility of cracking in the weldment due to the higher hardness and insufficient manufacturing practices caused by lack of knowledge for preheating, intermediate/final postweld heat treatment and other factors. The manufacturers have to establish the proper technologies to avoid this problem during fabrication stage while the pressure vessels are to be fabricated in their shop and/or fields. In this paper, the manufacturing technologies of 2.25Cr-1Mo-V steel pressure vessel through actual fabrication is presented herewith.

UNITEMP HX

Alloy Digest ◽  
1964 ◽  
Vol 13 (5) ◽  
Keyword(s):  
Fracture Toughness ◽  
Corrosion Resistance ◽  
High Temperature ◽  
Physical Properties ◽  
Base Material ◽  
Heat Treating ◽  
Operating Conditions ◽  
High Temperature Strength ◽  
Temperature Performance ◽  
Nickel Base

Abstract Unitemp-HX is a nickel-base material recommended for high temperature applications. It has outstanding oxidation resistance at high temperatures under most operating conditions, and good high-temperature strength. 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 low and high temperature performance, and corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: Ni-91. Producer or source: Universal Cyclops Steel Corporation.

ALUCHROM YHf

Alloy Digest ◽  
2004 ◽  
Vol 53 (1) ◽  
Keyword(s):  
Stainless Steel ◽  
Corrosion Resistance ◽  
High Temperature ◽  
North America ◽  
Physical Properties ◽  
Tensile Properties ◽  
Heat Treating ◽  
Pressure Vessels ◽  
Temperature Performance ◽  
Oxidation Resistant

Abstract Aluchrom YHf is an oxidation resistant ferritic stainless steel alloyed with aluminum. The alloy is approved in North America and Europe for pressure vessels to 899 deg C (1650 deg F). This datasheet provides information on composition, physical properties, elasticity, and tensile properties. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: SS-899. Producer or source: ThyssenKrupp VDM GmbH.

Effect of Carbide Content on Temper Embrittlement of 2.25Cr1Mo Steel

2016 ◽  
Author(s):  
Yian Wang ◽  
Guoshan Xie ◽  
Zheng Zhang ◽  
Xiaolong Qian ◽  
Yufeng Zhou ◽  
...  
Keyword(s):  
High Temperature ◽  
Pressure Vessel ◽  
High Stress ◽  
Temper Embrittlement ◽  
Damage Mechanism ◽  
Pressure Vessels ◽  
Nondestructive Method ◽  
Operating Conditions ◽  
Low Alloy Steels ◽  
Carbide Content

Temper embrittlement is a common damage mechanism of pressure vessels in the chemical and petrochemical industry serviced in high temperature, which results in the reduction of roughness due to metallurgical change in some low alloy steels. Pressure vessels that are temper embrittled may be susceptible to brittle fracture under certain operating conditions which cause high stress by thermal gradients, e.g., during start-up and shutdown. 2.25Cr1-Mo steel is widely used to make hydrogenation reactor due to its superior combination of high mechanical strength, good weldability, excellent high temperature hydrogen attack (HTHA) and oxidation-resistance. However, 2.25Cr-1Mo steel is particularly susceptible to temper embrittlement. In this paper, the effect of carbide on temper embrittlement of 2.25Cr-1Mo steel was investigated. Mechanical properties and the ductile-brittle transition temperature (DBTT) of 2.25Cr-1Mo steel were measured by tensile test and impact test. The tests were performed at two positions (base metal and weld metal) and three states (original, step cooling treated and in-service for a hundred thousand hours). The content and distribution of carbides were analyzed by scanning electron microscope (SEM). The content of Cr and Mo elements in carbide was measured by energy dispersive X-ray analysis (EDS). The results showed that the embrittlement could increase the strength and reduce the plasticity. Higher carbide contents appear to be responsible for the higher DBTT. The in-service 2.25Cr-1Mo steel showed the highest DBTT and carbide content, followed by step cooling treated 2.25Cr-1Mo steel, while the as-received 2.25Cr-1Mo steel has the minimum DBTT and carbide content. At the same time, the Cr and Mo contents in carbide increased with the increasing of DBTT. It is well known that the specimen analyzed by SEM is very small in size, sampling SEM specimen is convenient and nondestructive to pressure vessel. Therefore, the relationship between DBTT and the content of carbide offers a feasible nondestructive method for quantitative measuring the temper embrittlement of 2.25Cr-1Mo steel pressure vessel.

ZIRCONIA FIBERS AS A COMPONENT OF HIGH TEMPERATURE THERMAL INSULATION (review)

2021 ◽  
pp. 79-86
Author(s):  
V.G. Babashov ◽  
◽  
N.M. Varrik ◽  
Keyword(s):  
High Temperature ◽  
Thermal Insulation ◽  
Zirconium Oxide ◽  
Thermal Protection ◽  
Sol Gel ◽  
Precursor Solution ◽  
Technical Literature ◽  
Thermal Protection Systems ◽  
Insulation Materials ◽  
Protection Systems

Based on the analysis of recent publications of scientific and technical literature, data on the production of zirconium oxide fibers used for the manufacture of high-temperature thermal insulation materials are presented. Information is provided on various methods of obtaining zirconium oxide fibers (methods of impregnation of the template and molding of the mixture, sol-gel method of spinning a fiber-forming precursor solution), as well as on the technique of fiber molding (manual pulling, dry and wet spinning, blowing and electrospinning). The use of such fibers for the production of thermal insulation materials (felts, cords and blocks) instead of currently existing materials made of aluminum oxide-based fibers can significantly increase the operating temperatures of the thermal protection systems.

Novel Kevlar® pulp-reinforced alumina-silica aerogel composites for thermal insulation at high temperature

2022 ◽  
Author(s):  
Mariana E. Ghica ◽  
Cláudio M. R. Almeida ◽  
Laura S. D. Rebelo ◽  
Gabriel C. Cathoud-Pinheiro ◽  
Benilde F. O. Costa ◽  
...  
Keyword(s):  
High Temperature ◽  
Thermal Insulation ◽  
Silica Aerogel

Advancements in Fast Epitaxial High-Temperature Brazing of Single-Crystalline Nickel-Base Superalloys

2009 ◽  
Author(s):  
Britta Laux ◽  
Sebastian Piegert ◽  
Joachim Ro¨sler
Keyword(s):  
High Temperature ◽  
Gas Turbines ◽  
Base Material ◽  
Secondary Phases ◽  
Single Crystalline ◽  
Thermodynamic Simulations ◽  
Nickel Base Superalloys ◽  
Stray Grains ◽  
Nickel Base ◽  
Nickel Manganese

High temperature diffusion brazing is a very important technology for filling cracks in components from single-crystalline nickel-base superalloys as used in aircraft engines and stationary gas turbines: alloys, which are similar to the base material, are enhanced by a fast diffusing melting-point depressant (MPD) like boron or silicon, which causes solidification by diffusing into the base material. Generally, epitaxial solidification of single-crystalline materials can be achieved by use of conventional braze alloys, however, very long hold times are necessary to provide a complete diffusion of the MPD out of the braze gap. If the temperature is lowered before diffusion is completed, brittle secondary phases precipitate, which serve as nucleation sites for stray grains and, therefore, lead to deteriorating mechanical properties. It was demonstrated in earlier works that nickel-manganese-based braze alloys are appropriate systems for the braze repair of particularly wide gaps in the range of more than 200 μm, which allow a significant shortening of the required hold times. This is caused by the complete solubility of manganese in nickel: epitaxial solidification can be controlled by cooling in addition to diffusion. In this work, it will be shown that the nickel-manganese-based systems can be enhanced by chromium and aluminium, which is with regard to high-temperature applications a very important aspect. Furthermore, it will be demonstrated that silicon, which could be identified as appropriate secondary MPD in recent works, can be replaced by titanium, as this element has additionally a γ′ stabilizing effect. Several braze alloys containing nickel, manganese, chromium, aluminium and titanium will be presented. Previously, the influence of the above mentioned elements on the nickel-manganese-based systems will be visualized by thermodynamic simulations. Afterwards, different compositions in combination with a heat treatment, which is typical for nickel-base superalloys, will be discussed: a microstructure, which is very similar to that within the base material can be presented.

Thermal insulation characteristics of a lightweight, porous nanomaterial in high-temperature environments

2018 ◽  
Vol 140 ◽  
pp. 376-386 ◽  
Author(s):  
Haoyuan Ren ◽  
Dafang Wu ◽  
Junning Li ◽  
Wenjun Wu
Keyword(s):  
High Temperature ◽  
Thermal Insulation
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