The ASTM A182 F11 steel is the standard specification for forged or rolled alloy and stainless-steel pipe flanges, as well as forged fittings and all types of parts and valves for high-temperature service. This standard applies to forged low-alloy steel and stainless-steel pipe parts that are used in pressure systems. It also includes several grades of low-carbon alloy steel and ferritic, martensitic, austenitic, and ferritic-austenitic stainless steels. Therefore, it needs to be selected according to the use and design requirements.
Basic Information on the F11 Steel
Although the F11 steel isn't used as much as the F22 in the ASTM A182 category, this is still a popular type of steel used in numerous applications. The units are expressed in inch-pounds and SI units, and there are different types of the manufacturing process, including:

• Low-alloy ferritic steels should be smelted in open hearth furnaces, electric furnaces, or through the basis-oxygen process.
•  Stainless steel should be smelted via electric furnace or vacuum furnace.

Main Point of the Manufacture of the F11 Steel
Material for the steel needs to be forged as close as possible to the actual specified shape and size; when needing tees, U-bends, elbows, connecting tees, and any flange, these should not be processed directly from bars. The right alloy steel manufacture of these parts will make sure each part is made to the right specification so that you won't have to be concerned about getting something sub-standard.

13CrMo4-5/F11/ 1.7335 - Characteristics and application
13CrMo4-5 low alloy steel is a relatively low-carbon chrome-molybdenum grade compared to other related high temperature grades, characterized by good cold and hot workingability, excellent machinability, weldability while maintaining high strength properties at room temperature and elevated temperatures.
The closest equivalent of 13CrMo4-5, more commonly found in the form of products, is used as a half-finished product for parts and subassemblies for the power industry, as well as for chemical industry that work in the temperature up to 530 ºC - in contact with liquids containing various concentrations of "hard" substances, gases and steam that may contain numerous chemicals - pressure equipment components, boilers, turbines and power systems.
In the 13CrMo4-5 grade are made parts for the fittings for the installations - bottoms, flanges, knee, tees, profiles, seamless tubes, as well as bars, forgings, flat bars and hot rolled sheets with various thickness and dimensions. Earlier mentioned fittings are used for steam and other discharge ducts, such as pipelines and superheater pipes.
For hot rolled, forgings, and forged materials, these products are used for screws, nuts, struts and parts of boilers and steam turbines. Flat products - such as plates or tapes are used as parts for pressure vessels, turbine blades, steamers or steam collectors.
15HM steel is primarily delivered in heat-treated, softened, normalized and tempered state.
Mechanical properties in normalized state for individual dimensions
Tensile strength R_m 

• • Dimensions: <16 - 60mm = 450 - 600 N/mm²
  • Dimensions: 60 - 100mm = 440 - 590 N/mm²
  • Dimensions: 100 - 150mm = 430 - 580 N/mm²

• • Dimensions: <16mm = > 300 N/mm²
  • Dimensions: 16 - 60mm = > 295 N/mm²
  • Dimensions: 60 - 100mm = 275 N/mm²
  • Dimensions 100 - 150mm = > 255 N/mm²

• • Dimensions: 16 - 60mm = > 31 J

• • Dimensions: 16 - 60mm = > 20 %

• Softening annealing at the temperature of 600 - 700ºC
• Normalizing with cooling in calm air at the temperature of 910 - 940ºC
• Relief annealing with calm air cooling at the temperatures of 660 - 710ºC
• Hardening with cooling in water at the temperature of 890 - 910 ºC, when cooling in oil - 900 - 930 ºC
• Tempering in calm air at temperatures of 650 - 720 °C

DN15-DN3000
Maximum weight 6tons
25,000tons production annual year

ANSI B16.5,ANSI B16.47 Series A&B,ANSI B16.48,ANSI B16.36
API 605,API 16D,API 17D
BS4504,BS3293
DIN
AS
EN1092-1
GOST
EEMUA145