How to choose high temperature grade and material of valve

Have you ever learned about the high temperature grade of the valve and the selection of materials? Here is a brief introduction to the high temperature working conditions, which mainly include sub-high temperature, high temperature grade I, high temperature grade II, high temperature grade III, high temperature grade IV, and high temperature grade V. , are introduced separately below. 1. Sub-high temperature Sub-high temperature refers to the working temperature of the valve in the range of 325 to 425 °C. If the medium is water and steam, mainly use WCB, WCC, A105, WC6 and WC9. If the medium is sulfur-containing oil, C5, CF8, CF3, CF8M and CF3M, which are resistant to sulfide corrosion, are mainly used. They are mostly used in atmospheric and vacuum units and delayed coking units in oil refineries. At this time, valves made of CF8, CF8M, CF3 and CF3M are not used for corrosion resistance of acid solutions, but are used for sulfur-containing oil products and oil and gas pipelines. 2. High temperature class I When the working temperature of the valve is 425 ~ 550 ℃, it is high temperature class I (referred to as PI class). The main material of the PI grade valve is 'high temperature grade I medium carbon chromium nickel rare earth titanium high-quality heat-resistant steel' based on CF8 in the ASTMA351 standard. Because PI grade is a specific name, the concept of high temperature stainless steel (P) is included here. Therefore, if the working medium is water or steam, although high temperature steel WC6 (t≤540°C) or WC9 (t≤570°C) can also be used, and high temperature steel C5 (ZG1Cr5Mo) can also be used in the case of sulfur-containing oil, but in They cannot be called PI grades here. 3. High temperature grade II The valve's working temperature is 550-650℃, which is designated as high temperature grade II (referred to as PII grade for short). PII grade high temperature valve is mainly used in heavy oil catalytic cracking unit in oil refinery, it includes high temperature lined wear-resistant gate valve used in three-rotation nozzle and other parts. The main material of the PII grade valve is 'high temperature grade II medium carbon chromium nickel rare earth titanium tantalum reinforced heat-resistant steel' based on CF8 in the ASTMA351 standard. 4. High temperature grade III The working temperature of the valve is 650 ~ 730 ℃, which is designated as high temperature grade III (referred to as PIII grade). PIII grade high temperature valves are mainly used in large heavy oil catalytic cracking units in oil refineries. The main material of PIII grade high temperature valve is 'high temperature grade III medium carbon chromium nickel molybdenum rare earth titanium tantalum reinforced heat-resistant steel' based on CF8M in ASTMA351 standard. 5. High temperature grade IV The working temperature of the valve is 730~816℃, which is designated as high temperature grade IV (referred to as PIV grade). The upper limit of the working temperature of the PIV class valve is 816 °C because the maximum temperature provided in the standard ASMEB16134 pressure-temperature class selected for valve design is 816 °C (1500υ). In addition, after the working temperature exceeds 816 °C, the steel is close to entering the forging temperature region. At this time, the metal is in the plastic deformation range, and the metal has good plasticity, and it is difficult to withstand high working pressure and impact force without deformation. The main material of the PIV grade valve is CF8M in the ASTMA351 standard as the base shape 'high temperature grade IV medium carbon chromium nickel molybdenum rare earth titanium tantalum reinforced heat-resistant steel'. 6. The working temperature of the high temperature V level valve>Above 816℃, referred to as PⅤ grade for short, PⅤ grade high temperature valve (for shut-off valves, not for regulating butterfly valves) must adopt special design methods, such as lining with heat insulation lining or water or air cooling, etc. To ensure the normal operation of the valve. Therefore, the upper limit of the working temperature of the PⅤ grade high temperature valve is not specified, because the working temperature of the control valve is not only solved by materials, but by special design methods, and the basic principles of the design methods are the same. PⅤ grade high temperature valve can choose reasonable materials that can meet the valve according to its working medium and working pressure and the special design method adopted.
Owing to its types of industrial valves and types of industrial valves benefits, has become a buzzword in the types of industrial valves market.
Serving others for customers a better life with valve application for employees respect and opportunity.
If you are looking for best product, then here are some product like valve application, types of industrial valves and types of industrial valves in various styles which will surely meet your demand. Visit Lianke Valve to know more!
Utilizing high technology to manufacture products can afford a fully experience to customers by using valve application.