Monel Alloy Valves for Corrosive Application
Monel is a kind of Ni-Cu solid solution, in which Cu is added as a non-oxidizing resist based on Ni, which reinforces the alloy and also improves the corrosion resistance of alloy. The casting properties of alloy is also improved by the added Carbon, but only 0.15% of Carbon can be dissolved in the alloy at normal temperature, and the excess Carbon will be analyzed as graphite phase. The addition of 1.5% to 3.5% Fe can also improve the casting properties of alloy. and the addition of Mn and Si improves the mechanical properties of alloy. In particular, the content of Si has an important influence on the mechanical and physical properties of Monel alloy.
Monel alloys are available in two categories: cast alloys and deformed alloys (rolled materials).
There are more than 10 kinds of deformed Monel alloys in the United States. Such as Monel400, MonelC, Monel403, Monel404, Monel R405, Monel406, Monel411, MonelK500, Monel501 and Monel502. Because Monel has its own representation in different US standard systems, in the US UNS, nickel alloys have five grades of modified Monel alloys, solid solution-enhanced NO4404 (Monel400), NO4404 (Monel404) and NO4405 ( MonelR-405), and precipitation hardening type NO5500 (MonelK500) and NO5502 (Mone1502), etc. (Table 1). Among them, the modified Monel alloy used for the production of corrosion resistant valves are the Monel400 and MonelK500.
The grade B Monel alloy with high Si content (3.5%) is mainly used for the manufacturing of abrasion resistant shafts and wear rings, because of its high strength, corrosion and abrasion resistance. Grade D Monel alloys (4.0% Si) are used to make parts that require higher wear and corrosion resistance.
Monel alloy valves are available in two types, full and part.
The full Monel alloy valve means that valve body and trims are Monel, which is mainly used in the HF acid regeneration tower section of the refinery alkylation unit. Due to its high temperature (149 ° C) and water content, full Monel alloy is required for the valve. In addition, the full Monel valve is also used in the production of ashless additives for refinery catalysts and working conditions with high concentration in chlor-alkali plants, and etc.
The part Monel alloy valve means that the valve body is made of carbon steel or stainless steel, but its trim is made of Monel alloy. The valve is mainly used in the low temperature region of the HF acid system of the refinery alkylation unit. Carbon steel has good corrosion resistance for anhydrous hydrofluoric acid (HF) at low temperature (≤71 °C), but it will produce a film on the surface of steel when it is used for a long time. If carbon steel is used in the valve sealing part, the film will affect the sealing performance of valve.
The commonly used sealing material 13Cr in carbon steel valves is not resistant to the corrosion of HF acid, but Monel alloy is corrosion resistance , thus ensures the good sealing performance of valve. Further, the part Monel alloy valve is much cheaper than the full Monel alloy valve. Monel alloy valves made of carbon steel can also be used in medium like seawater. Valve with stainless steel body and Monel alloy trim can be applied in ethylene, propylene, liquid oxygen, pure oxygen, seawater and other working conditions. When full and part monel alloy valve is used in the alkylation unit, class 300 is required for safety reasons. In other conditions, when part monel alloy valve is applied, valve can be of Class150 and Class 300 , or PN1.6~6.4MPa, etc.
Monel gate valve, Monel ball valve, Monel check valve, Monel globe valve, Monel plug valve, Monel butterfly valve
Monel alloys are available in two categories: cast alloys and deformed alloys (rolled materials).
There are more than 10 kinds of deformed Monel alloys in the United States. Such as Monel400, MonelC, Monel403, Monel404, Monel R405, Monel406, Monel411, MonelK500, Monel501 and Monel502. Because Monel has its own representation in different US standard systems, in the US UNS, nickel alloys have five grades of modified Monel alloys, solid solution-enhanced NO4404 (Monel400), NO4404 (Monel404) and NO4405 ( MonelR-405), and precipitation hardening type NO5500 (MonelK500) and NO5502 (Mone1502), etc. (Table 1). Among them, the modified Monel alloy used for the production of corrosion resistant valves are the Monel400 and MonelK500.
The grade B Monel alloy with high Si content (3.5%) is mainly used for the manufacturing of abrasion resistant shafts and wear rings, because of its high strength, corrosion and abrasion resistance. Grade D Monel alloys (4.0% Si) are used to make parts that require higher wear and corrosion resistance.
Monel alloy valves are available in two types, full and part.
The full Monel alloy valve means that valve body and trims are Monel, which is mainly used in the HF acid regeneration tower section of the refinery alkylation unit. Due to its high temperature (149 ° C) and water content, full Monel alloy is required for the valve. In addition, the full Monel valve is also used in the production of ashless additives for refinery catalysts and working conditions with high concentration in chlor-alkali plants, and etc.
The part Monel alloy valve means that the valve body is made of carbon steel or stainless steel, but its trim is made of Monel alloy. The valve is mainly used in the low temperature region of the HF acid system of the refinery alkylation unit. Carbon steel has good corrosion resistance for anhydrous hydrofluoric acid (HF) at low temperature (≤71 °C), but it will produce a film on the surface of steel when it is used for a long time. If carbon steel is used in the valve sealing part, the film will affect the sealing performance of valve.
The commonly used sealing material 13Cr in carbon steel valves is not resistant to the corrosion of HF acid, but Monel alloy is corrosion resistance , thus ensures the good sealing performance of valve. Further, the part Monel alloy valve is much cheaper than the full Monel alloy valve. Monel alloy valves made of carbon steel can also be used in medium like seawater. Valve with stainless steel body and Monel alloy trim can be applied in ethylene, propylene, liquid oxygen, pure oxygen, seawater and other working conditions. When full and part monel alloy valve is used in the alkylation unit, class 300 is required for safety reasons. In other conditions, when part monel alloy valve is applied, valve can be of Class150 and Class 300 , or PN1.6~6.4MPa, etc.
Monel gate valve, Monel ball valve, Monel check valve, Monel globe valve, Monel plug valve, Monel butterfly valve
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