Pipes are hollow, long tubes that are used for a variety of purposes. They are produced in two ways, resulting in a welded or a seamless pipe. This blog gives more explanation about ASTM A335 P22 Seamless Pipes.
WHAT IS A SEAMLESS PIPE
Seamless pipe is no different than the word itself, which means “smooth and without seams or obvious joins”. A steel cylindrical bar is used to make the Seamless pipe. The bar is heated to a high temperature before inserting a probe and creating a hole through the cylinder. After that, the cylinder is moved to rollers, which size it to the desired diameter and thickness.
WHAT IS ASTM A335 P22
ASTM A335 is a standard that refers to an alloy and P22 is it’s Grade. Alloy pipes contain higher percentages of alloying elements such as molybdenum (Mo), chromium (Cr), nickel (Ni), and other elements. The ASTM A335 Seamless Pipes standard applies to “low-alloy” steel pipes, whose total alloying element content is less than 5%. Higher percentages of alloying elements (for example, nickel and chromium) transform steel into higher alloys such as stainless steel, duplex steel, and super-alloyed materials such as Inconel, Hastelloy, Monel, and other super-alloyed materials.
CHEMICAL COMPOSITION OF ASTM A335 P22
Carbon (C) – from 0.05% to 0.15%
Manganese (Mn) – from 0.30% to 0.60%
Chromium (Cr) – from 1.90% to 2.60%
Molybdenum (Mo) – from 0.87% to 1.13%
Phosphorus (P) – max. 0.025%
Sulfur (S) – max. 0.025%
Silicon (Si) – max. 0.50%
MECHANICAL PROPERTIES –
Tensile Strength, MPa : 415 min
Yield Strength, MPa : 205 min
HEAT TREATMENT
Type : Full or Isothermal Anneal, or Normalize and Temper
Tempering Temperature Range : 1250°F [675°C]
CHARACTERISTICS
Some of the primary characteristics of P22 Seamless Pipes are mentioned below.
- Corrosion resistance
- High tensile strength
- Wear resistance
- Smooth edges
- Enhanced strength
- Increased hardenability
ASTM A335 P22 APPLICATIONS
P22 is appropriate for high-temperature environments, such as those found in the following industries:
- Pharmaceutical equipment
- Seawater equipment
- Pulp and paper
- Off-shore Oil drilling companies
- Chemical equipment
- Petrochemicals
- It is also extensively used in making steam boilers, boiler parts, boiler drums, pressure vessels, condensers, and heat exchangers.
