See which welding and fabrication companies actually hold AWS D1.1, EN 1090, or ISO 3834, not just ISO 9001. Ranked by certification depth, with the checks to run before sending an RFQ.
The top welding and fabrication companies include Tianjin Lanruisheng Technology, Shanghai Hanshen, Changsha Meiyu Electric Appliance, Suzhou Xiyi/Jiangsu Juli Intelligent Machinery, Jianhu County Hengtai Machinery, Kingtiger Industrial, Changzhou Yichuang Energy Technology, Dalian Botong Processed Metals, Westmoreland Steel & Fabrication, All-Type Welding and Fabrication, TruFusion Steel, and Blue Horizon Fabrication. Of these 12 companies, 2 list EN 1090, 4 list ISO 3834, and 3 list AWS D1.1.
Rather than ranking companies by reviews or revenue, this list focuses on welding-specific codes and certifications. Only 3.1% of the China-based welding factories in our data list ISO 3834 and 0.9% list EN 1090, compared with 78.7% listing ISO 9001.
The result is a more useful comparison of welding capability, including where a company’s certifications do not match the work it is recommended for.
2 things separate a shop that appears on a list from one that can deliver your weldment: a certification matching your application's code, and documented experience in your vertical. Both are below, and this goes deeper on welded assemblies than our metal fabrication companies comparison.
A third factor isn't in the table, because factory profiles don't record it consistently: which welding processes each shop runs. Confirm MIG/GMAW, TIG/GTAW, Stick/SMAW or FCAW directly before shortlisting anyone. Our comparison of MIG and TIG welding covers the two you'll meet most often.
|
Welding and fabrication company |
Region |
Certification on file |
Best fit for |
|
Tianjin Lanruisheng Technology Co., Ltd |
China / Tianjin |
EN 1090, EN 15085, ISO 3834, ISO 9001; 5,000–10,000 m² |
Wind power, rail and photovoltaic structural welding |
|
Shanghai Hanshen Co., Ltd. |
China / Shanghai |
EN 1090, ISO 3834, ISO 9001, ISO 14001, ISO 45001; 30,000+ m² |
Elevator and general industrial assemblies. No EN 15085 on file |
|
Changsha Meiyu Electric Appliance Co., Ltd |
China / Hunan |
EN 15085, ISO 3834, ISO 9001; 30,000+ m² |
Rail-transit structural members and cabinets |
|
Suzhou Xiyi Trading Co., LTD. / Jiangsu Juli Intelligent Machinery Co., LTD |
China / Jiangsu |
ISO 3834, ISO 9001, ISO 14001, ISO 45001, VDA 6.1; 30,000+ m² |
Elevator, escalator and construction machinery structures |
|
Jianhu County Hengtai Machinery Manufacturing Co., Ltd |
China / Jiangsu |
GJB 9001C-2017, ISO 9001, ISO 14001, ISO 45001; 30,000+ m² |
Engineering, petroleum and agricultural machinery components |
|
Kingtiger Industrial Co., Limited |
China / Guangdong |
ISO 9001 only; 3,000–5,000 m² |
General welded sheet metal and structural parts |
|
Changzhou Yichuang Energy Technology Co., LTD |
China / Jiangsu |
ISO 9001 only; 10,000–30,000 m² |
Energy-sector fabrication. No ASME certification on file |
|
Dalian Botong Processed Metals LLC |
China / Liaoning |
ISO 9001 only; 1,000–3,000 m² |
Drilling equipment weldments. No API certification on file |
|
Westmoreland Steel & Fabrication, Inc. |
U.S. / New Stanton, PA |
ISO 9001:2015 (PRI, cert. 24178), AWS D1.1, D1.3, D15.1, ASME Section IX; CWI on staff, NDE |
Heavy steel and defence fabrication, Buy America contracts |
|
All-Type Welding and Fabrication, Inc. |
U.S. / Glenwillow, OH |
ISO 9001, AWS D1.1, D1.2, D1.6, D17.1; 34,000 ft² |
Multi-material aerospace, defence and food-grade fabrication |
|
TruFusion Steel |
U.S. / Riverside, CA |
States AWS D1.1; CSLB #1106970 (C-51 Structural Steel) |
Structural steel fabrication and erection in Southern California |
|
Blue Horizon Fabrication, LLC |
U.S. / Waynesburg, PA |
No certifying body or standard number published |
Mid-Atlantic pipe and structural welding, subject to confirming qualification |
Every China welding and fabrication factory in the above table has been through our own vetting: a checked business licence, an on-site audit, and a review of the equipment and certifications the profile claims, the same process we cover in full in our guide to finding reliable CNC machining companies in China.
Changsha Meiyu holds EN 15085 for rail welding. The rest list ISO 9001 or an industry standard such as GJB 9001C-2017, and Blue Horizon publishes no certifying body or standard number at all. None of that disqualifies a shop, but it means its welding quality system is taken on trust rather than audited.
Tianjin Lanruisheng Technology is 1 of only 2 factories in our reviewed set disclosing EN 1090, the European conformity route for structural steel. It pairs that with EN 15085 for rail welding, plus ISO 3834 and ISO 9001, across a 5,000–10,000 m² Tianjin facility making fuel and hydraulic tanks, photovoltaic mounting and wind power structures, the kind of energy component manufacturing that needs both codes. That combination is rare, so ask your account manager for the notified body and execution class on the certificate: an EXC2 certificate won't carry an EXC3 job.
Best fit: Wind power, rail and photovoltaic structural welding for European-code programmes.
Shanghai Hanshen is the second EN 1090 holder here, running a 30,000+ m² Shanghai facility also certified to ISO 3834, ISO 9001, ISO 14001 and ISO 45001. Its welded range covers elevator car bottoms and counterweight frames, escalator step chain assemblies, and air pipe assemblies. As with Tianjin Lanruisheng, ask for the notified body and execution class on this certificate too. And note it holds no EN 15085, so rail work needs that certificate confirmed separately.
Best fit: EN 1090 structural welding for elevator and general industrial assemblies.
Changsha Meiyu Electric Appliance holds EN 15085, the European rail welding standard, alongside ISO 3834 and ISO 9001 across a 30,000+ m² Hunan facility. EN 15085 runs from CL1 to CL4, and CL4 covers organisations that don't weld at all, so ask which level the certificate names. Despite the company name, its capability set is weighted to welded fabrication and assembly rather than finished appliances.
Best fit: Rail-certified welded structural members and construction machinery cabinets.
Suzhou Xiyi Trading Co., LTD. / Jiangsu Juli Intelligent Machinery Co., LTD lists ISO 3834 alongside ISO 9001, ISO 14001, ISO 45001 and VDA 6.1, from a 30,000+ m² Suzhou factory making automated smart parking systems, elevator car tops and counterweight frames, and escalator drive units.
One caveat on that VDA 6.1: the VDA is retiring it, so it stops being certifiable after 31 December 2028 and remaining certificates lapse on 1 January 2029. For automotive weldments, ask for IATF 16949 instead.
Best fit: Elevator, escalator and construction machinery welded structures.
Jianhu County Hengtai Machinery holds GJB 9001C-2017, China's defence quality management standard, alongside ISO 9001, ISO 14001 and ISO 45001, from a 30,000+ m² Jiangsu facility producing shafts, valve blocks and industrial structural components.
Read that certification for what it is. Part A is an equivalent adoption of GB/T 19001-2016, China's version of ISO 9001:2015, and Part B adds the defence-contracting requirements alongside it. So it's a management standard, not a material or performance grade, it makes a company eligible to bid on Chinese military work rather than evidence it does any, and it carries no standing on a European or US defence programme.
Best fit: Shafts and structural components for engineering, petroleum and agricultural machinery.
Kingtiger Industrial carries ISO 9001 across more than 50 listed sectors, from a 3,000–5,000 m² Dongguan facility producing industrial welded components, control cabinet racks and precision sheet metal. That breadth cuts both ways: a shop listing 50+ sectors rarely has depth in any one, and Kingtiger lists Pressure Vessel while holding no ASME certification. Treat it as a general fabricator, not a code shop.
Best fit: General welded sheet metal and structural components where no welding code applies.
Changzhou Yichuang Energy Technology lists Oil & Gas, Pressure Vessel and Boiler Industry among its focus areas, in the same energy-sector manufacturing category as turbine housings and valve bodies, from a 10,000–30,000 m² ISO 9001 certified Jiangsu facility. But a pressure vessel needs an ASME "U" Certificate of Authorization, and there's none on this profile. Check the ASME certificate-holder directory before treating it as a code shop.
Best fit: Non-code energy-sector fabrication and structural work.
Dalian Botong Processed Metals names products for oil field drilling directly: frac gun parts, oil well drilling parts and general weldments, from a 1,000–3,000 m² ISO 9001 certified Liaoning facility. Wellhead and frac equipment runs to API 6A, 20B or 20C with API Specification Q1 behind it, not the pipeline code, and none of those is on this profile. API publishes a Composite List of licensees, so that one is checkable.
Best fit: Non-code drilling equipment weldments and general oil and gas fabrication.
Westmoreland Steel has the deepest welding-code stack in this comparison, and its defence-programme work sits in the same aerospace and defence manufacturing category buyers compare it against. Its published compliance record names AWS D1.1 for structural steel, D1.3 for sheet steel, D15.1 for cars and locomotives, and ASME Section IX, with a Certified Welding Inspector on staff and non-destructive examination in house.
Westmoreland's ISO 9001:2015 certificate is public: number 24178, issued by PRI Certification, covering precision metal fabrication, welding, assembly and painting. It operates from New Stanton, Pennsylvania and handles Buy America and DFARS-compliant material sourcing.
Best fit: Heavy steel fabrication for defence and government programmes with domestic-preference clauses.
All-Type Welding and Fabrication has operated since 1987 from Glenwillow, Ohio, which the company describes as a Cleveland suburb. Its welding qualifications span AWS D1.1, D1.2, D1.6 and D17.1 from a 34,000 ft² ISO 9001 certified facility.
Those 4 AWS codes tell you the material range directly, because D1.2 is aluminium, D1.6 is stainless and D17.1 is aerospace. This is a multi-material shop working carbon steel, stainless, aluminium and nickel alloys for aerospace and defence, foodservice, pharmaceutical and OEM work.
All-Type also lists MIL-STD-1595A and MIL-STD-2219A, both cancelled, in 1998 and 2009. Any supplier presenting either as current is quoting a withdrawn document.
Best fit: Multi-material aerospace and defence fabrication where D1.2, D1.6 or D17.1 applies.
TruFusion Steel operates from Riverside, California and holds California contractor licence #1106970 in classification C-51, Structural Steel. The company states it welds to AWS D1.1 in SMAW, GMAW and FCAW, and also runs CNC laser and heavy-plate plasma cutting.
Take the AWS D1.1 claim as self-attested: AWS qualifies welders and procedures, so no registry of D1.1-certified companies exists. State filing records show the LLC was registered in December 2019; the contractor licence has been on file since 2023.
Best fit: Structural steel fabrication and erection in Southern California.
Blue Horizon Fabrication was formed as a West Virginia domestic LLC on 18 December 2017 and operates from Waynesburg, Pennsylvania, serving Pennsylvania, Ohio, West Virginia, Maryland and Virginia. It specialises in pipe welding and structural fabrication for natural gas, pipeline, power generation and construction work.
Blue Horizon's public materials advertise "certified welding" but name no certifying body and no standard number. Pipeline work would normally mean API 1104 or ASME Section IX qualification, so ask for the welder qualification records directly.
Best fit: Mid-Atlantic pipe and structural welding, subject to confirming qualification.
Application scope, certification fit, welding process capability, vertical experience and sourcing region are the 5 things to confirm before you send a welding RFQ.
Scope and certification work together, and getting that pairing wrong is the expensive mistake. A structural steel job calls for AWS D1.1 or EN 1090, a pressure vessel calls for an ASME "U" stamp built on Section VIII, and a pipeline calls for API 1104. A certificate that doesn't cover your application protects nothing.
|
RFQ check for welding and fabrication |
What to confirm |
Why it matters |
|
Application scope |
Structural steel, pipeline, pressure vessel, or general fabrication |
A structural shop isn't automatically qualified for vessels |
|
Certification fit |
The code, part and class: EN 1090-1 with execution class, ISO 3834 Part 2/3/4, AWS D1.1, API 1104, ASME Section VIII |
An unqualified certificate name hides the level held |
|
Welding process capability |
MIG/GMAW, TIG/GTAW, Stick/SMAW or FCAW, and on which materials |
Process fit drives weld quality, speed and cost |
|
Vertical experience |
Prior work in your sector, not a list of served industries |
Listed breadth is not depth in any one |
|
Sourcing region |
Field-based or shop-based, and the landed cost |
Freight can erase a unit-price saving |
ISO 9001 is near-universal and welding-specific certification is rare, which is what makes the second category useful as a filter at all, the same gap our metal stamping QA comparison finds in a different process.
|
Certification |
Share of welding-capable China factory profiles |
|
ISO 9001 |
78.7% |
|
ISO 14001 |
22.7% |
|
IATF 16949 |
22.2% |
|
ISO 45001 |
15.1% |
|
ISO 13485 |
5.8% |
|
GJB 9001C-2017 |
4.9% |
|
ISO 3834 |
3.1% |
|
EN 1090 |
0.9% |
The gap between ISO 9001 and ISO 3834 is roughly 25x, and that gap is the entire sourcing problem. Filtering on ISO 9001 leaves you 79% of the market; filtering on the welding standard leaves a shortlist you can work through in an afternoon.
Jiangsu, Zhejiang and Guangdong account for 81.8% of the welding-capable factories we reviewed.
|
China province |
Share of welding-capable factory profiles |
|
Jiangsu |
33.8% |
|
Zhejiang |
24.4% |
|
Guangdong |
23.6% |
|
Shanghai |
6.7% |
|
Shandong |
2.2% |
|
Anhui |
2.2% |
|
Liaoning |
2.2% |
|
Hebei |
1.8% |
|
Other provinces, including Tianjin and Hunan |
3.1% |
That last row matters more than its size suggests, because 2 of the strongest factories in this comparison sit inside it. Tianjin Lanruisheng is in Tianjin and Changsha Meiyu is in Hunan, and neither province reaches 2% of the set. Concentration tells you where capacity is, not where your supplier is.
A factory in one of those three provinces sits inside an established supply chain, with easier access to raw material, subcontractors and export logistics.
China fits best once the drawing, code requirement and volume are fixed and the work is shop-fabricated, because a locked specification lets a verified factory quote and produce at scale. That reverses the moment a welder has to be on site, which is why local shops win field welding, pipeline tie-ins, and jobs where an engineer needs to walk the floor mid-production.
But freight decides more of these calls than certification does, and it's what most comparisons leave out. Welded assemblies are bulky and heavy, so ocean freight, duties and inland haulage routinely erase a unit-price saving that looked decisive on the quote. Compare landed cost, never unit price, and get the freight number before you award.
The other risk worth naming is quality fade: a supplier performs well for 2 or 3 years, then quietly moves production to a subcontractor or cuts inspection frequency, and nothing in the original audit catches it. Re-audit on a schedule, write change control into the contract so production can't move without notice, and keep first-article inspection alive on repeat orders.
|
Sourcing region for welding and fabrication |
Best fit |
What to watch for |
|
United States |
Field welding, pipeline tie-ins, on-site erection, direct inspection access |
Higher unit cost; published certification claims often unverifiable |
|
China |
Shop-fabricated structural, energy and equipment welding at repeat volume |
Freight and duties on bulky weldments; notified-body EN 1090; quality fade |
ASME Section IX and API 1104 both qualify welding procedures and welders, but for different applications. Section IX supports ASME pressure vessels and B31 piping, while API 1104 focuses on pipelines and related facilities.
The key difference is acceptance criteria: API 1104 evaluates welds for pipeline service, while Section IX works within construction codes governing design and materials. Qualification to one does not automatically qualify a shop for the other. For code-stamped ASME vessels, buyers should also verify the shop’s ASME “U” Certificate of Authorization.
AWS D1.1 is the American Welding Society's Structural Welding Code for steel, and it qualifies welders and welding procedures rather than certifying companies. There's no such thing as an AWS-certified D1.1 company, so a shop making that claim should produce welder qualification records, a Welding Procedure Specification, a Procedure Qualification Record, and access to a Certified Welding Inspector.
For US structural steel, AISC certification is the stronger shop-level signal, because it audits the facility's quality system rather than individual procedures. It carries no standing under EU construction-products law though, so if you're buying into Europe, EN 1090-1 is the certificate that counts.
Ask for the inspection package before you award, not after first delivery: the non-destructive examination method and extent, the acceptance criteria and their standard, a first-article inspection report, and material test reports tied to actual heat numbers.
Agree what happens when a weld fails, too. Quality risk is the second most cited barrier in our own buyer survey, at 59%, and most of it traces back to unwritten expectations, the same pattern our China sourcing FAQ covers for other processes. Put the response deadline, remake terms, who pays return freight, and the escalation path into the purchase order.
Match the certification to the code your job invokes, confirm the welding processes the shop runs, and check prior work in your vertical, ahead of company size or list position. Then establish whether the job is field-based or shop-based, because that decides whether overseas sourcing is available at all. Get those right and a verified Chinese factory becomes a real option; get them wrong and the certificate on the quote protects nothing.
To test this against your own drawing, submit an RFQ for custom welding services and compare what each factory profile's certifications actually cover.