Having Weldment Done in China 1

[MadMango]

This is the first time this I have ever had to procure a weldment outside the USA. It is comprised of 9 parts, all T304, which is required to be powder coated afterwards. W are ordering 200 weldments.

What pitfalls should I be aware of?
What are the common;y overlooked aspects regarding specifications to use?
Do I have to specify packaging for transit?
I don't know what else I don't know... please enlighten me.

"Art without engineering is dreaming; Engineering without art is calculating."

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[metengr]

I take it from your email you have no specification or contract document that outlines what is required in terms of welding process, weld joint details, inspection hold points and document to be submitted.

Having no clue what these parts are for, first, you need to know the end use of the parts to select a fabrication (welding) standard. Second, comes developing a purchase specification that specifies what welding standard is being invoked, joint detail, welding process, inspection hold points and final documents to be sent to you. Yes, transit and shipping must be discussed and agreed upon.
Third, is sitting down with the vendor to review the above and discuss your expectations.

What I provided above are for parts that are used in applications where welding is being used for structural or load-bearing purposes.

Since this is a small order, a second approach to the above might be if the pieces are not in an application where welding is being for structural purposes and only decorative purposes, send them a prototype that you want duplicated (and details on how you produced it), and have them reverse engineer it.


Oh, have them send you their prototype not the one you sent them, and inspect their prototype to ensure you are happy with it before you approve the order for the remainder. This might be the easiest approach and give you some level of quality rather than having the vendor try to re-design it on their own. Shipping and transit along with insurance should be agreed upon.

 

[BUGGAR]

Not sure about your specific product, but you will have to have quality control not only on what they fabricate themselves but also on their suppliers (see bogus bolts, welding electrodes, etc.). You don't want another Takata incident.

 

[weldstan]

First, you must specify all of your requirements, including those pertaining to shipping/delivery in the P.O. Technical requirement can be included in your drawing(s)
Second, don't expect that you will receive the items as defined in the P.O. without reliable source inspection, during fabrication and prior to shipping.

 

[desertfox]

hi

My company deal in china for fabricated and welded components and we have had some bad experiences.
What you need are your own trusted engineers/ inspectors watching over them and where required instructing them, if you don't you will end up with a pile of scrap but if you keep on there shoulder they can produce some good stuff.

 

[boo1]

How can you post delivery inspect, if they are powder coated?

 

[kingnero]

Having done simular things, but in europe with a supplier in hungary, I can tell you this is a disaster waiting to happen.
If there is a way they can cheap out on you, they will. Have them check with you every step of the way.
Review tolerances, welding procedures, filler metal, welding sequence, preparation, grinding afterwards, pickling if necessary, what to do in case of fukkups (repair procedures), ...
I agree with the prototype order. Specify that everything not done as in the prototype will void any purchase of the item. Be prepared that whatever is specified in the contract will not be followed.

Good luck and I sincerely hope this will work out for you and your company.

 

[MJCronin]

IMHO, it seems to me that for certain un-inspectable weldments, it would be wise to consider only domestic fabricators.

Even though the price may be a bit more expensive, the assurance of having the force of contract law behind the order may eliminate many worries.

The added advantage of having registered, known domestic inspectors (not the brother-in-law of the plant manager)looking after the product is significant.

Was domestic assembly and powder coating considered for this order ?

Did the managers and MBAs decide that China was the best choice for fabrication, then leave "all those messy quality issues" to the engineering staff ?

Tell us more.......

MJCronin
Sr. Process Engineer

 

[arunmrao]

If this is your first time, why do you not consider some reputed out sourcing agencies inUS. You may pay about 10% ,but you are sure about delivery at right time . Else, it is a challenge, no matter how careful you are. Time zone, language, culture differences, are some of the challenges you can face.

I'm just one step away from being rich, all I need now is money.
( read somewhere on the internet)

 

[tbuelna]

Contrary to what you might believe, there are some very capable welders in China. Having welding performed by a Chinese company is not much different than having the welding performed by any other foreign company. Make sure your PO defines exactly what you require in the delivered product. And make sure the Chinese vendor is qualified and capable of performing the work.

Caveat emptor.

 

[MadMango]

Further details- this is a mounting frame for a solar panel that is mounted to an 8m tall horizontal, 2" sch40 pole. We have had prototypes built domestically without issue.

I think that you have all touched on my biggest concern, being that we won't have "engineering eyes" on the process steps. We do have four quality inspectors on the ground there, but I am not familiar with them as they are from a different branch of the company. We are now thinking about requesting dye penetrate testing on samples, and 100% proof load testing prior to powder coating. We are also thinking about creating Go/No Go gauges. Is it acceptable to ask to review and approve jigs and fixtures for this weldment?

I do not have a feel for how large the contract manufacturer is, so I can't guess if 200pcs is a large are tiny order for them. I don't know if it will be manual or automated. They could very well be capable of running all 200 in a day, or they may only produce 5 a day. Our company has never dealt with weldments before, so I have little faith in the QA/QC process simply due to unfamiliarity.

"Art without engineering is dreaming; Engineering without art is calculating."

Have you read faq731-376 to make the best use of these Forums?

 

[boo1]

QA must be part of your contract.
See example Minimum Quality Control Guidelines for Gas Metal Arc Welding at

http://www.lear.com/user_area/extranet_files/lear-79-Weld_Guidelines.pdf

Consider
including material certification.
procuring uncoated (so you can inspect)
Tyically jigs inspection are not part of contracts, unless you are fuunding them
Packaging is very important for painted parts

 

[desertfox]

Hi MadMango

My company had a lot of welding done in China and we provided drawings with standards quoted, material specifications etc, it made no difference because we did not have eyes on the ground, we required X-ray's on critical joints so what they did was X-ray one joint then photocopied it and used that for all the other joints that they should of X-rayed but didn't bother, we ended up having 90% of the work repaired.
So my company will not do anymore business in China unless we have people watching over them.

 

[DekDee]

Mad Mango,
I have spent the past 10 years working as an inspector in Asia (China, Thailand, Malaysia & the Phillipines) and it basically comes down to you get what you pay for.
If you send product overseas for fabrication you will save money but if you do not have inspectors on the ground there is a strong possibility your repair / rework will cost more than the original savings.
Be very wary of using local TPI's (I base that statement on numerous past bad experiences).
A local contract inspector may work for you for a few weeks and then when he is released he may try getting a job with the very same contractor he has just been inspecting.
The chances of the contractor looking favourably on someone who has just cost them a lot of money for picking up poor workmanship are not very good.
There is also the possibility he / she has worked directly for the contractor previously and it is always difficult to criticise friends / colleagues.
Good luck with your project,
Regards,
DD

 

[tbuelna]

Based on the description of the weldment and the fairly modest quantity (200 pcs) I don't see the cost/benefit of having these components produced in China. For 200 pcs of a fairly simple welded structure you should be able to find a qualified local vendor to do the work for an acceptable price. Plus you would avoid the hassle and delays of working with an overseas vendor.

 

[MadMango]

tbuelna, factors that I know little about are contributing to cost savings by directly shipping from China to Brazil, rather than from the USA. The weldment is 1/4 of a total system.

All, I've passed on my concerns (thanks to your help is focusing them), that's about all I can do that I am aware of.

"Art without engineering is dreaming; Engineering without art is calculating."

Have you read faq731-376 to make the best use of these Forums?

 

[MikeHalloran]

Mango, you are working for idiots.

Get out.



Mike Halloran
Pembroke Pines, FL, USA

 

[chicopee]

Good luck on collecting for damages if "toomezhing" goes awry.

 

[msquared48]

50 percent down. 50 percent after all the welds pass X-Ray inspection here. 20 percent bonus if all the welds pass inspection.

Mike McCann, PE, SE (WA)

 

[tbuelna]

tbuelna, factors that I know little about are contributing to cost savings by directly shipping from China to Brazil, rather than from the USA. The weldment is 1/4 of a total system.

The shipping route from China to Brazil is not exactly "direct". In fact it is about as far a route around the globe as you can imagine.