Gr7 Titanium Pipe ASTM B338 High Cost For Container Equipment
Product Introduction
Titanium possesses excellent corrosion resistance, particularly the
Ti-0.2Pd titanium alloy, which is why GR7 titanium alloy is widely
utilized as a sealing material for container equipment. The GR7
titanium alloy offers superior corrosion resistance, and its
performance in reducing acids significantly surpasses that of pure
titanium, exhibiting enhanced resistance to crevice corrosion
compared to pure titanium. However, the inclusion of the metal
palladium in titanium-palladium alloys leads to increased costs,
which can limit their extensive application. Due to its outstanding
corrosion resistance, GR7 titanium pipes are extensively used in
chemical plants.
It is an alloyed form of titanium, containing standard levels of
oxygen with the addition of palladium, resulting in exceptional
corrosion resistance. This makes it highly suitable for use in
condensers, heat exchangers, water treatment facilities,
desalination processes, evaporators, pipelines, and it is also
employed in bicycle frames and other components.
Alloy GR7 titanium signifies the addition of a small amount of
palladium to pure titanium, making it currently the most
corrosion-resistant among all available titanium alloys. This grade
is particularly well-suited for applications requiring resistance
to general and localized crevice corrosion across a broad range of
reducing acid environments, including those with chlorides, as well
as conditions where low pH and high temperatures ranging from 180ºF
(83ºC) to 500ºF (260ºC) are present. Additionally, it demonstrates
good strength, weldability, and formability characteristics.
Chemical Requirements
| Grade | N | C | H | Fe | O | Al | V | Pd | Ti | other |
| gr7 | 0.03 | 0.08 | 0.015 | 0.3 | 0.25 | / | / | 0.12-0.25 | bal | <0.1 |
Mechanical Properties
| Grade | Tensile Strength min | Yield Strength 0.2% offset | Elongation min,% |
| Ksi | Mpa | Ksi | Mpa |
| gr7 | 50 | 345 | 40 | 275 | 20 |
Inspection Terms Of Grade7 Titanium Pipe
Test items | Water pressure test |
Ultrasonic test |
X-ray test |
Eddy current test |
Flaring and Flattening test. |
Specification:
The GR7 titanium alloy family includes variations such as Ti-0.2Pd,
Ti-0.15Pd, and Ti-0.13Pd, with Ti-0.2Pd titanium pipes being more
extensively used in various industrial components like reactors,
towers, autoclaves, heat exchangers, pumps, valves, centrifuges,
separators, pipes, fittings, and electrolyzers. GR7 is a
titanium-palladium alloy where the metal "palladium" is
incorporated into the smelting of sponge titanium. This process
involves vacuum melting to produce a grade 7 titanium alloy ingot.
The material is known for its corrosion resistance and is
predominantly utilized within the chemical industry. Its inspection
procedures include water pressure testing, ultrasonic testing, eddy
current testing, and tests for flaring and flattening.
Main components of the alloy consist of Titanium (Ti) as the
balance, with palladium (Pd) ranging from 0.12 to 0.25, Nitrogen
(N) not exceeding 0.03, Carbon (C) not surpassing 0.08, Hydrogen
(H) at or below 0.013, Iron (Fe) limited to 0.250, and Oxygen (O)
kept under 0.15.
The governing standard for this alloy is ASTM B338. Its physical
properties are characterized by a density of 4.51g/cm^3. Mechanical
properties include a tensile strength range of 270Mpa to 410Mpa,
yield strength of at least 165Mpa, and an elongation rate of 27% or
higher.
The production statuses encompass hot working condition (R), cold
working condition (Y), annealing condition (M), and solid solution
condition (ST).
