The heat treatment was 200 degree F ramp rates per hr up to 1375 degrees F, hold at 1375 degrees F for 2 hrs, and 200 degree F ranmp rates to 600 degrees F. We cooled under insulation after 600 degrees F. Preheat was 400 degrees F with a max interpass temp. of 600 degrees F. metengr (Materials) 31 Mar 15 21:33
Full Answer
What is heat treatment of pipe?
Heat treatment of pipe depends on the way it is manufactured – hot finished or cold finished. Selection of heat treatment methods will depend on types of material and on what material properties you want to restore or further enhancement on existing properties.
Why choose chrome moly pipe for power generation?
As a result, The chrome moly pipe finds high usage in power generation industry and petrochemical industry owing to its resistance to corrosion, tensile strength, strength for high temperature owing to its cost-effectiveness.
What are the different grades of chrome moly pipe?
This chrome moly pipe featured grades are ASTM A335 P5, P9, P11, P22, P91, so also it could be called as P Grade pipe in some cases. P11 pipe, P22 pipe and P91 pipes are used in power industry and petro-chemical plants, meanwhile, P5 and P9 pipe generally find usage in refineries.
What is 9crmov steel?
It is a chromium-molybdenum pipe and tube. 9CrMoV. It is a creep strength-enhanced ferritic steel (CSEF) used primarily for strength or enhanced corrosion resistance at elevated temperatures. A213 T91 (seamless tube), A335 P91 (seamless pipe). Is that maybe what you are talking about? It is also 8.00 - 9.50 % chrome.
What is chrome moly pipe?
This chrome moly pipe featured grades are ASTM A335 P5, P9, P11, P22, P91, so also it could be called as P Grade pipe in some cases.#N#P11 pipe, P22 pipe and P91 pipes are used in power industry and petro-chemical plants, meanwhile, P5 and P9 pipe generally find usage in refineries.
What is the chromium level in stainless steel?
Chromium is a key component that is used in the manufacture of stainless steel. If the chromium levels are above 12% , it can be classified as stainless steel. The oxidation resistance potential of chrome is irreplaceable even in elevated temperatures.
What is P91 pipe?
ASTM A335 Grade P91 pipe is premium grade pipe applied for high pressure boiler. And P91 pipe is ideal when it comes to bending, flanging or when it is used in similar operations such as welding. The material of steel should stick to the composition of chemicals, tensile property and the requirements of hardness.
Is tensile strength better at high temperatures?
The hardness, tensile and yield strength is better at standard temperatures. Due to the composition of the material, it is ideal to be used in power plants, refineries, petro-chemical plants and other oil field services when there is transportation under high temperatures and pressures involved.
What is chrome moly?
The A335 pipes are generally called chrome moly pipe as they have a high level of Chromium and Molybdenum presence in it. While Molybdenum increases the overall strength, resistance, elasticity, hardenability and overall quality, moly ensures that the material is more resistant to softening, restrains the growth of grains and lessens the chances ...
What is A335 pipe used for?
ASTM A335 pipe (with Grade P9, P11, P22, P91 pipes) has been widely used in different industries for high temperature, high pressure services. According to market data, it is one of the most consumption alloy pipes in boiler industry, heat exchanger, power station, high and super high pressure vessels.
What is a P91 pipe?
It shall be noted that, ASTM A335 Grade P91 pipe is a good grade pipe applied for high pressure boiler. And P91 pipe is ideal when it comes to bending, flanging or when it is used in similar operations such as welding. The material of steel should stick to the composition of chemicals, tensile property and the requirements of hardness.#N#ASTM A335 P91 alloy steel pipe and high pressure boiler pipes are the two variants available and the range is dependent based on the size, which is solely based on the usage. The length of the pipe will be subject to hydrostatic test and there will also be a non-destructive examination based on the specifications.
Is chrome a stainless steel?
If the chromium levels are above 12%, it can be classified as stainless steel. The oxidation resistance potential of chrome is irreplaceable even in elevated temperatures. The hardness, tensile and yield strength is better at standard temperatures.
What is the process of heat treating iron?
The length of time typically depends on the thickness of the metal and similar factors. Tempering:- Tempering is a process of heat treating, which is used to increase the toughness of iron-based alloys.
Why do metals need heat treatment?
The most common reasons that metals undergo heat treatment are to improve their strength, hardness, toughness, ductility, and corrosion resistance.
What is normalizing steel?
Normalizing:- Normalizing involves heating steel, and then keeping it at that temperature for a period of time, and then cooling it in air. The resulting microstructure is a mixture of ferrite and cementite which has a higher strength and hardness, but lower ductility.
How does hardening work?
Hardening:- Hardening is a metallurgical metalworking process used to increase the hardness of a metal. The hardness of a metal is directly proportional to the uniaxial yield stress at the location of the imposed strain. A harder metal will have a higher resistance to plastic deformation than a less hard metal. Precipitation hardening also known as age hardening, is one of the Hardening processes. It creates uniformity in a metal’s grain structure, making the material stronger. The process involves heating a solution treatment to high temperatures after a fast cooling process. Precipitation hardening is usually executed in an inert atmosphere at temperatures ranging from 900 degrees Fahrenheit to 1,150 degrees Fahrenheit. It can take anywhere from an hour to four hours to carry out the process. The length of time typically depends on the thickness of the metal and similar factors.
What is precipitation hardening?
Precipitation hardening also known as age hardening, is one of the Hardening processes. It creates uniformity in a metal’s grain structure, making the material stronger. The process involves heating a solution treatment to high temperatures after a fast cooling process.
What is hardening metal?
Hardening:- Hardening is a metallurgical metalworking process used to increase the hardness of a metal. The hardness of a metal is directly proportional to the uniaxial yield stress at the location of the imposed strain. A harder metal will have a higher resistance to plastic deformation than a less hard metal.
How long does it take for precipitation hardening to take place?
It can take anywhere from an hour to four hours to carry out the process. The length of time typically depends on the thickness of the metal and similar factors.
