ASTM A335 P9 High Temperature Alloy Steel Tube For Heat Exchanger Black Painted

ASTM A335 P9 High Temperature Alloy Steel Tube For Heat Exchanger Black Painted

TONG CHUANG Group has been operating stainless steel/duplex/nickel for more than 10 years， with annual sales of more than 80，000 tons of stainless steel/duplex/nickel. Our clients have covered more than 45 countries. Our Stainless Steels are widely used in mining， energy， petrochemical， chemical， food mills， paper mills， gas and fluid industries and more.

ASTM A335 P9 grade， also commonly known as ASME SA335 P9 grade pipe， is a seamless ferritic alloy steel pipe mainly used for high temperature applications. The UNS designation for this grade P9 is K90941. ASTM A335 Grade P9 pipes have a minimum yield strength of 205 MPA， while their minimum yield strength is 415 MPA. The minimum elongation for these pipes is approximately 30/20 L/T. Phosphating， passivation， shot peening， oil immersion and varnishing are some of the possible surface treatments for A335 pipe. These pipes can be tested by a variety of methods including flattening， surface and dimension， mechanical properties， hardness， chemical composition， inspection， bending， etc.

These pipes have a variety of uses and are therefore used in many industries such as boilers， chemical， power， petroleum， oil and gas. These pipes are widely used due to two important properties – one is its high corrosion resistance， and the other is its ability to operate at high and low temperatures. These pipes have excellent machinability and weldability， making them ideal for flanging and bending. P9 piping is built for high temperature service and is therefore highly recommended for cokers， hydrocrackers， high temperature and ultra-high temperature lines， reheat lines， etc.

The addition of molybdenum ("Moly") increases the strength and elastic limit of the steel and enhances the wear resistance， impact quality and hardenability of the steel. It also improves softening resistance， makes chrome steel less brittle and prevents pitting corrosion.

Chromium is also a key element in stainless steel alloys， preventing oxidation of the steel at high temperatures and improving the corrosion resistance of the steel. It improves tensile， yield and hardness properties of low alloy pipes at room temperature.
Other alloying elements， present to varying degrees in all grades of pipe:
Aluminum: Reduces oxygen in steelmaking
Boron: used to produce fine grains and increase steel hardness
Cobalt: Used to improve heat and wear resistance of steel
Manganese: Provides better steel hardenability
Nickel: Improves toughness， hardenability and impact strength at low temperatures
Silicon: Reduces oxygen， improves hardenability and toughness
Titanium: prevents the precipitation of chromium carbide
Tungsten: refines the grain size of the steel and increases the hardness of the steel， especially at high temperatures
Vanadium: enhances the fatigue resistance of steel
As mentioned earlier， low alloy steels have less than 5% total alloying elements; high alloy steels have higher percentages of these elements.

Chemical Composition of ASTM A335 P9

Mechanical Propertities of ASTM A335 P9