Titanium Grade 7 Welded Tube
Grade: Grade 7
Main Composition: Ti-0.12～0.25Pd
Condition: Annealed
Surface Finish: Mill finish, pickled, bright annealed
Common Standards: ASTM B337/B338 , ASME SB337/SB338, ISO 8539
Description
Technical Parameters
Introduction
Titanium Grade 7 welded tube is added with Pd to drastically boost resistance to reducing acids, crevice corrosion, and low-pH/stagnant conditions.
It is a palladium-alloyed commercially pure α titanium tube. It is manufactured by roll forming and welding titanium strip. It has greatly improved corrosion resistance over standard Grade 2.
Physical & Mechanical Properties
|
Property |
Typical Value |
|
Density |
4.51 g/cm³ |
|
Melting Point |
~1668°C |
|
Tensile Strength |
≥483 MPa (70 ksi) |
|
Yield Strength (0.2% offset) |
≥345 MPa (50 ksi) |
|
Elongation (in 50 mm) |
≥20% |
|
Hardness (Rockwell B) |
70–80 |
Manufacturing & Welding Process
Base Material: Cold-rolled Grade 7 titanium strip; strict chemical & surface control.
Forming: U-O-E or roll-forming into tubular shape.
Welding: Primarily GTAW (TIG) with ER Ti-7 filler wire; full internal+external argon shielding to avoid oxidation and nitridation of hot zones. Laser welding is also used for thin-wall tubes.
Annealing: Post-weld annealing to restore ductility; no PWHT needed for most corrosion services.
Inspection: 100% X-ray and ultrasonic testing for weld integrity; pressure testing, dimensional check, surface inspection.
How to inspect quality?
Standard inspections:
Chemical analysis
Mechanical properties
Hydrostatic / pneumatic pressure test
Eddy current or ultrasonic test
Dimensional check
Intergranular corrosion test (if required)
What are typical applications?
Heat exchangers (chemical, desalination, marine)
Piping for chemical processing
Flue gas desulfurization (FGD)
Chlor-alkali equipment
Seawater cooling systems
Pulp & paper bleaching systems
Grade 7 vs. Grade 2 welded tube
Grade 2: Good corrosion resistance in oxidizing and neutral media.
Grade 7: Same mechanical properties as Grade 2, but with Pd alloying to resist crevice corrosion and reducing acids.
Why choose welded over seamless Grade 7 tube?
Welded: more cost-effective, consistent dimensions, better for thin wall and long lengths.
Seamless: used for very high-pressure or ultra-critical applications.Grade 7 welded tube is widely accepted for heat exchangers and process piping.
Additional Information
Payment term
We accept T/T, L/C, Credit Card,Paypal,Western Union,Moneygram,etc
Packing
Be packed in wooden case and then put on pallet, we can also supply customizable packaging.
shipping methods
We supply the various shipping methods as below:
By express: DHL, UPS, FEDEX, TNT, SF, CR express, Postal express,By air cargo or By sea/ocean.
FAQ
Q: Can Grade 7 welded tube be used in seawater?
+
-
A：Yes. In seawater, especially at elevated temperatures where Grade 2 may suffer crevice corrosion.
Q: What welding process is used?
+
-
A: Mostly GTAW (TIG) welding with full argon shielding. Laser welding is also used for thin-wall precision tubes.
Q: Do you need post-weld heat treatment?
+
-
A: Usually not required for corrosion service. Stress-relief or annealing may be done for dimensional stability or improved ductility.
Q: Is Grade 7 welded tube expensive?
+
-
A: It costs more than Grade 2, but much lower than high nickel alloys for similar corrosive service. Lower lifetime cost due to long service life.
Q: Can it be bent or fabricated?
+
-
A: Yes, it has good ductility and can be bent, flared, and machined with proper tooling in annealed condition.
Ruihang Group mainly produces the titanium raw materials for your precision manufacturing. For more details,please reach us to the email: Sam.Rui@bjrh-titanium.com
Hot Tags: titanium grade 7 welded tube, China titanium grade 7 welded tube manufacturers, suppliers, factory, Gr12 TItanium Welded Tube, Gr5 Titanium Welded Tube, Gr5 Titanium Seamless Tube, titanium alloy tubes, Gr9 TItanium Welded Tube, Gr7 TItanium Welded Tube
Previous
Titanium Grade 12 Welded TubeSend Inquiry
