摘要:
One embodiment of the invention includes a cermet composition represented by the formula (PQ)(RS) comprising: a ceramic phase (PQ) and a binder phase (RS) wherein,P is a metal selected from the group consisting of Al, Si, Mg, Ca, Y, Fe, Mn, Group IV, Group V, Group VI elements, and mixtures thereof,Q is oxide,R is a base metal selected from the group consisting of Fe, Ni Co, Mn and mixtures thereof,S consists essentially of at least one element selected from Cr, Al and Si and at least one reactive wetting element selected from the group consisting of Ti, Zr, Hf, Ta, Sc, Y, La, and Ce.
摘要:
Cermets are provided in which a substantially stoichiometric metal carbide ceramic phase along with a reprecipitated metal carbide phase, represented by the formula MxCy, is dispersed in a metal binder phase. In MxCy M is Cr, Fe, Ni, Co, Si, Ti, Zr, Hf, V, Nb, Ta, Mo or mixtures thereof, x and y are whole or fractional numerical values with x ranging from 1 to 30 and y from 1 to 6. These cermets are particularly useful in protecting surfaces from erosion and corrosion at high temperatures.
摘要:
An insert for reducing sulfidation corrosion and depositional fouling is disclosed. The insert is formed from a corrosion and fouling resistant steel composition containing a Cr-enriched layer and having a surface roughness of less than 40 micro inches (1.1 μm).
摘要:
Provided is a bimetallic tube for transport of hydrocarbon feedstocks in refinery process furnaces, and more particularly in furnace radiant coils, including: i) an outer tube layer being formed from stainless steels including chromium in the range of 15.0 to 26.0 wt. % based on the total weight of the stainless steel; ii) an inner tube layer being formed from an alumina forming bulk alloy including 5.0 to 10.0 wt. % of Al, 20.0 wt. % to 25.0 wt. % Cr, less than 0.4 wt. % Si, and at least 35.0 wt. % Fe with the balance being Ni, wherein the inner tube layer is formed plasma powder welding the alumina forming bulk alloy on the inner surface of the outer tube layer; and iii) an oxide layer formed on the surface of the inner tube layer, wherein the oxide layer is substantially comprised of alumina, chromia, silica, mullite, spinels, or mixtures thereof.
摘要:
Provided is a bimetallic tube for transport of hydrocarbon feedstocks in refinery process furnaces, and more particularly in furnace radiant coils, including: i) an outer tube layer being formed from stainless steels including chromium in the range of 15.0 to 26.0 wt. % based on the total weight of the stainless steel; ii) an inner tube layer being formed from an alumina forming bulk alloy including 5.0 to 10.0 wt. % of Al, 20.0 wt. % to 25.0 wt. % Cr, less than 0.4 wt. % Si, and at least 35.0 wt. % Fe with the balance being Ni, wherein the inner tube layer is formed plasma powder welding the alumina forming bulk alloy on the inner surface of the outer tube layer; and iii) an oxide layer formed on the surface of the inner tube layer, wherein the oxide layer is substantially comprised of alumina, chromia, silica, mullite, spinels, or mixtures thereof.
摘要:
Provided is a bimetallic tube for transport of hydrocarbon feedstocks in a petrochemical process unit and/or refinery process unit, including: i) an outer tube layer being formed from a steam cracker alloy including at least 18.0 wt. % Cr and at least 10.0 wt. % Ni; ii) an inner tube layer being formed from an alumina forming bulk alloy including 5.0 to 10.0 wt. % of Al, 18.0 wt. % to 25.0 wt. % Cr, less than 0.5 wt. % Si, and at least 35.0 wt. % Fe with the balance being Ni, wherein the inner tube layer is formed plasma powder welding the alumina forming bulk alloy on the inner surface of the outer tube layer; and iii) an oxide layer formed on the surface of the inner tube layer, wherein the oxide layer is substantially comprised of alumina, chromia, silica, mullite, spinels, or mixtures thereof.
摘要:
Multimodal cermet compositions comprising a multimodal grit distribution of the ceramic phase and method of making are provided by the present invention. The multimodal cermet compositions include a) a ceramic phase and b) a metal binder phase, wherein the ceramic phase is a metal boride with a multimodal distribution of particles, wherein at least one metal is selected from the group consisting of Group IV, Group V, Group VI elements of the Long Form of The Periodic Table of Elements and mixtures thereof, and wherein the metal binder phase comprises at least one first element selected from the group consisting of Fe, Ni, Co, Mn and mixtures thereof, and at least second element selected from the group consisting of Cr, Al, Si and Y, and Ti. The method of making multimodal boride cermets includes the steps of mixing multimodal ceramic phase particles and metal phase particles, milling the ceramic and metal phase particles, uniaxially and optionally isostatically pressing the particles, liquid phase sintering of the compressed mixture at elevated temperatures, and finally cooling the multimodal cermet composition. Advantages disclosed by the multimodal cermets are high packing density of the ceramic phase, high fracture toughness and improved erosion resistance at high temperatures up to 1000° C. The disclosed multimodal cermets are suitable in high temperature erosion/corrosion applications in various chemical and petroleum environments.
摘要:
Alloy compositions which are resistant to metal dusting corrosion are provided by the present invention. Also provided are methods for preventing metal dusting on metal surfaces exposed to carbon supersaturated environments. The alloy compositions include an alloy (PQR), and a multi-layer oxide film on the surface of the alloy (PQR). The alloy (PQR) includes a metal (P) selected from the group consisting of Fe, Ni, Co, and mixtures thereof, an alloying metal (Q) comprising Cr, Mn, and either Al, Si, or Al/Si, and an alloying element (R). When the alloying metal (Q) includes Al, the multi-layer oxide film on the surface of the alloy includes at least three oxide layers. When the alloying metal (Q) includes Si, the multi-layer oxide film on the surface of the alloy (PQR) includes at least four oxide layers. When the alloying metal (Q) includes Al and Si, the multi-layer oxide film on the surface of the alloy (PQR) includes at least three oxide layers. The multi-layer oxide film is formed in situ during use of the alloy composition in a carbon supersaturated metal dusting environment. Advantages exhibited by the disclosed alloy compositions include improved metal dusting corrosion resistance at high temperatures in carbon-supersaturated environments having relatively low oxygen partial pressures. The disclosed alloy compositions are suitable for use as the inner surfaces in reactor systems and refinery apparatus.
摘要:
A method and apparatus for reducing fouling associated with a process stream in a heat transfer component. The method and apparatus include the use of one of a vibration producing device to impart a vibrational force to desired component and a pulsation producing device for apply pressure pulsations to the process stream. The heat transfer component has at least one surface having a surface roughness of less than 40 micro inches (1.1 μm).
摘要:
A cermet composition represented by the formula (PQ)(RS)X comprising: a ceramic phase (PQ), a binder phase (RS) and X wherein X is at least one member selected from the group consisting of an oxide dispersoid E, an intermetallic compound F and a derivative compound G wherein said ceramic phase (PQ) is dispersed in the binder phase (RS) as particles of diameter in the range of about 0.5 to 3000 microns, and said X is dispersed in the binder phase (RS) as particles in the size range of about 1 nm to 400 nm.