Frequently Asked Questions
1. How can Argweld® HotPurge® help me?
HotPurge® Pipe Weld Purging Systems for Heat Treated Chrome and High Strength Stainless Steels were developed for the welding of chrome steel pipe joints where the post weld heat treatment temperatures may be as high as 300ºC (572ºF). These Systems will allow you to generate zero colour coke free welds without any defect caused by harmful gases or vapours. If you have any welding tasks where the heat generated might be too high for the other pipe purging systems in our range, it might well be appropriate to use HotPurge® Systems.
2. What range of sizes is available?
6 to 88” (152 to 2,235 mm).
3. What is the overall length?
The dimensions between the dams vary from 28-36”. In the event that you order your HotPurge® Systems for working with bends in the pipework then the dimensions will be greater.
4. Can Argweld® HotPurge® Systems be used for'return bends'?
Yes, as long as you make it clear at your enquiry stage, that you will be pulling the HotPurge® Systems through bends, then we can adjust the Systems accordingly.
5. Are Argweld® HotPurge® Systems re-usable?
You should be able to use your Systems for many heat treated weld joints as long as it is used within its specification and hasn’t been damaged.
6. What gases can I use with Argweld® HotPurge® Systems?
These Systems are intended to be used with totally inert argon gas of at least 99.995% purity. It is very important that the System is placed within the pipe prior to heating and that the purge gas is turned on at the beginning of the heat treating cycles and remains on until the units are deflated and withdrawn at the end of the PWHT cycle.
7. What are Argweld® HotPurge® Systems made from?
HotPurge® Systems are fabricated from high temperature resistant materials.
8. How cost-effective are Argweld® HotPurge®?
Using localised purging will save a lot of money in inert gas costs, by not having to purge whole pipe Systems and not having to pay for the cost of extra waiting time.
9. Are Argweld® HotPurge® Systems resistant to heat?
The materials selected for HotPurge® manufacture are resistant to the temperatures that are expected during the heat treatment of chrome steels for weld joint manufacture.
10. How do I measure the residual oxygen content?
HFT® manufactures a range of Weld Purge Monitors®. The PurgEye® 100 IP65 is the best general purpose Weld Purge Monitor® on the market today. If you need to purge down to oxygen levels less than 100 ppm, then the PurgEye® 200 IP65 or any of the others in the range will be suitable as they all measure very accurately down to 10 ppm.
11. How do I position the product in the pipeline?
There are pull loops that each have up to a 1,000lb breaking strain. These can be connected to pull wires that will pull the HotPurge® System from joint to joint.
12. How long will HotPurge® Systems remain inflated?
HotPurge® Systems remain inflated until the purge gas hose is detached.