Precision Welding Services in China — TIG, MIG, Robotic & Fish Scale Welding, AWS D1.1
ISO 9001:2015 Certified | Fish Scale Welding | HAZ-Controlled | NDT Inspection | SS 316L, Al 6061, CS | No MOQ
Precision welding fuses metal components using controlled heat input to form a continuous, load-bearing joint — with process choice (TIG, MIG, or robotic) determined by material, thickness, and required weld appearance. We perform AWS D1.1/D1.2/D1.6-qualified TIG, MIG, and robotic MIG welding on stainless steel, aluminum, and carbon steel assemblies up to 8–10 tonnes.
Every weld is verified with NDT inspection — Visual (VT), Dye Penetrant (PT), Magnetic Particle (MT), or Ultrasonic (UT). Our senior welders are also qualified for fish scale TIG welding, a premium aesthetic bead technique used on visible, high-end assemblies.
-
✔ ISO 9001:2015 Certified
-
✔ AWS D1.1 / D1.2 / D1.6 Compliant WPS
-
✔ Certified Welding Masters
-
✔ Robotic MIG Welding Cells
-
✔ Fish Scale Welding Capability
-
✔ NDT Inspection (VT, PT, MT, UT available)
Expert Fabrication & Rapid Turnaround at Qingdao Inside Industry
Welding Capabilities & Process Specifications
Process selection is not arbitrary — each welding method has specific advantages that align with particular material types, thicknesses, production volumes, and quality requirements. Our engineering team selects the optimal method during DFM review, before any arc is struck.
| Process | Method | Max Material Thickness | Best For | Key Advantage |
| Manual TIG (GTAW) | Gas Tungsten Arc Welding | SS: 12mm / Al: 8mm / CS: 16mm | Precision joints, visible welds, medical/food-grade | Finest bead control; fish scale welds; lowest spatter |
| Manual MIG (GMAW) | Gas Metal Arc Welding | SS: 20mm / Al: 12mm / CS: 25mm | Structural frames, heavy assemblies, high deposition | Fast deposition; good penetration; cost-effective on volume |
| Robotic MIG | Automated GMAW | SS: 16mm / Al: 10mm / CS: 20mm | High-volume OEM runs; repeatable weld geometry | Consistent bead quality; no operator fatigue; 24/7 operation |
| Pulsed TIG | Controlled-pulse GTAW | SS: 8mm / Al: 6mm | Thin-gauge stainless, aluminum heat management | Reduced heat input; minimal distortion; clean spatter-free |
| Spot Welding | Resistance Spot Welding | 0.5–3mm per layer | High-speed thin-sheet assembly | No filler; no distortion; fastest for sheet-on-sheet joints |
| Laser Welding | Fiber Laser Beam Welding | SS: 4mm / Al: 3mm | Micro-precision; medical; electronics | Narrowest HAZ; highest accuracy; cosmetic-grade result |
Precision Control for Visible and Critical Joints
Gas Tungsten Arc Welding (TIG) uses a non-consumable tungsten electrode to create the arc, with filler added separately by the welder. This independent control over heat input and filler addition allows the welding master to produce precise, narrow, high-quality beads — essential for:
– Medical device enclosures in SS 316L where cosmetic appearance and contamination prevention are paramount
– Aluminum 6061-T6 structural frames where controlled heat input prevents distortion and preserves temper
– Thin-gauge stainless steel (0.5–3mm) components for food equipment and pharmaceutical applications
– Fish scale (TIG stack) welds where aesthetic bead pattern is a design requirement
Productivity for Structural and High-Volume Work
Gas Metal Arc Welding (MIG) feeds filler wire continuously through a gun with integrated shielding gas. Higher deposition rates make MIG the preferred method for:
– Heavy carbon steel structural frames, bases, and equipment enclosures (material 3–25mm)
– High-volume OEM production runs where consistent bead quality must be maintained across 500+ pieces
– Multi-pass fillet welds on thick assemblies requiring high structural strength
– Galvanized steel assemblies where controlled shielding gas protects the zinc coating at the weld zone
Consistent Quality at Scale
Our robotic welding cells combine CNC-programmed torch paths with real-time seam tracking to deliver human-quality welds with machine-level repeatability. Robotic welding is standard for:
– OEM assemblies of 200+ pieces where identical weld geometry across every part is contractually required
– Rectangular and prismatic frames where torch paths can be programmed and locked for production
– High-deposition structural welds where operator fatigue would otherwise cause quality variation on long shifts
– Automotive and industrial components requiring documented weld parameters for PPAP or process audits
Fast, Clean Thin-Sheet Assembly
Resistance spot welding joins two sheets by passing high current through a copper electrode contact point. No filler metal, no shielding gas, no distortion from arc heat. Ideal for:
– Enclosure panels, brackets, and sheet-on-sheet assemblies in 0.5–3mm gauge
– High-speed assembly of galvanized steel components (automotive, HVAC, construction)
– Assemblies where cosmetic surface appearance must be maintained on the non-weld face
| Parameter | Specification |
| Welding Standards | AWS D1.1 (Structural Steel), AWS D1.2 (Aluminum), AWS D1.6 (Stainless Steel) |
| Procedure Documents | Formal WPS (Welding Procedure Specification) per process-material combination |
| Welder Qualification | AWS-certified welding masters; PQR (Procedure Qualification Records) maintained |
| Shielding Gas (TIG/MIG) | Argon (Al), Argon/CO₂ 80/20 (CS MIG), Pure Argon (SS TIG), Tri-mix He/Ar/CO₂ (SS MIG) |
| Post-Weld Treatment | Passivation (SS), anodizing prep (Al), grinding, brushing, pickle paste on request |
| Max Assembly Size | Structural frames up to 5m (5,000mm) length; heavy assemblies up to 8–10 tonnes (by arrangement) |
| NDT Methods Available | Visual (VT), Dye Penetrant (PT), Magnetic Particle (MT), Ultrasonic (UT), Leak Test (LT) |
Fish Scale TIG Welding — Aesthetic High-Performance Weld Beads
Fish scale welding (also known as TIG Stack Welding or ripple bead welding) is a manual TIG welding technique where the welder creates a series of overlapping, uniform semicircular bead patterns by rhythmically oscillating the torch and feeding filler in a controlled sequence. The result is a visually distinctive weld with a uniform, rippled appearance resembling fish scales — simultaneously an engineering achievement and an aesthetic statement.
Why Fish Scale Welding Matters for B2B Buyers
Aspect | Standard TIG Bead | Fish Scale TIG Bead |
Visual appearance | Smooth, flat bead — functional | Uniform ripple pattern — architectural quality |
Heat input control | Standard for material type | Higher control — smaller heat pulses reduce HAZ |
Welder skill requirement | Certified TIG welder | Senior master welder — significantly higher skill |
Application fit | General industrial joints | Visible welds on high-end products, food/medical equipment, motorsport |
Inspection difficulty | Standard VT inspection | Consistent pitch and width measured as quality indicator |
Buyer signal | Standard capability | Premium capability — differentiates supplier quality tier |
Our Fish Scale Welding Process
Every fish scale weld is performed under a formal WPS (Welding Procedure Specification) that defines: filler wire grade and diameter, shielding gas composition and flow rate, pre-heat temperature, arc travel speed and oscillation frequency, and inter-pass temperature limits for multi-pass applications.
Welder qualification for fish scale work is separate from standard TIG certification. Our fish scale welding masters are tested quarterly on standard specimens, with photographic documentation of bead pattern consistency maintained in our quality records.
– Pitch tolerance: scale spacing maintained within ±0.5mm across the full weld length
– Width consistency: bead width variation <10% along any 100mm measurement length
– Penetration: full root fusion verified by cross-section test coupon per batch
Key Features of Our Sheet Metal Welding Services — 5 Technical Advantages
Precision Engineering, HAZ Control & Documented Quality for Industrial OEM Projects
High-Temperature Fusion Process
Our precision welding services use localized heating to melt the base metal and filler material, creating a continuous metallurgical bond upon cooling. This fusion — rather than mechanical joining — ensures long-term structural stability under load. Deep penetration and zero porosity are verified per WPS.
Diverse Welding Methodologies
We offer 6 welding processes — TIG, MIG, robotic MIG, pulsed TIG, resistance spot welding, and fiber laser welding. Each process is selected during DFM review based on material, thickness, and required weld appearance. Full WPS documentation per process-material combination.
Exceptional Joint Strength
Welded joints achieve tensile strength comparable to — and often exceeding — the parent metal. Full root fusion is verified by cross-section test coupon per batch. Ideal for structural applications in industrial machinery where reliability under heavy load is critical.
The Heat-Affected Zone (HAZ)
We manage the heat-affected zone (HAZ) through material-specific parameters: SS 316L passivation, Al 6061-T6 pulsed TIG, and CS preheat per AWS D1.1 Table 3.2. Documented inter-pass temperature control preserves hardness and corrosion resistance in the weld zone.
Stringent Quality Demands
Every weld undergoes VT inspection as standard, with PT, MT, UT, and leak testing available per application. Inspection results are documented with weld traveler cards linking operator, WPS, and results. AWS D1.1/D1.2/D1.6 qualified procedures.
Why Global OEMs Choose Our Welding Services
Advantage | Evidence |
| ISO 9001:2015 Certified WPS | Formal Welding Procedure Specifications for each process-material combination. PQR (Procedure Qualification Records) maintained. WPS + PQR package available for customer audit. |
| Fish Scale Welding Capability | Senior welding masters qualified for TIG stack (fish scale) technique. Scale pitch tolerance ±0.5mm. Bead width consistency <10% variation. Photographic quality records per batch. |
| HAZ Management per Material | Material-specific HAZ mitigation: SS 316L passivation; Al 6061-T6 pulsed TIG; CS preheat per AWS D1.1 Table 3.2. Documented inter-pass temperature control. |
| Multi-Method NDT Inspection | VT standard on all assemblies; PT, MT, UT, and leak testing available per application. Inspection results documented with weld traveler cards linking operator, WPS, and results. |
| Robotic Welding for OEM Consistency | Robotic MIG cells with seam tracking for high-volume OEM runs. Weld parameters locked after first-article approval. Identical bead geometry guaranteed across 50–5,000 piece runs. |
| One-Stop Fabrication | Laser cutting -> bending -> welding -> surface finishing -> assembly under one ISO 9001 roof. One PO, one QC system, one delivery. |
Welding Material Challenges & Solutions — 6 Common Metals
How We Weld Stainless Steel, Carbon Steel, Aluminum, Magnesium, Copper & Titanium
Each metal has specific welding challenges — from heat input control to oxidation risk. Below are the 6 primary materials we weld, with the key challenge and our solution for each.
Stainless Steel — Oxidation Control & Passivation
Challenge: High chromium content forms a passive oxide layer that can cause incomplete fusion if not properly shielded.
Our Solution: TIG (GTAW) and MIG (GMAW) with argon shielding; post-weld passivation per ASTM A380 to restore corrosion resistance in the HAZ. Full MTR traceability for SS 304/316L programs.
Carbon Steel — Preheat & Hydrogen Cracking Prevention
Challenge: High carbon content (>0.3%) can cause hydrogen-induced cracking in the HAZ if preheat and inter-pass temperature are not controlled.
Our Solution:Low-hydrogen MIG (ER80S-D2 / ER90S-G) with preheat per AWS D1.1 Table 3.2. PWHT on request for high-strength grades (S420, S460, HSLA).
Aluminum & Alloys — Heat Input & Oxide Management
Challenge: High thermal conductivity (5× steel) draws heat away from the weld zone, causing lack-of-fusion. Aluminum oxide (Al₂O₃) melts at 2,072°C — far above aluminum’s 660°C — requiring AC TIG or pulsed TIG.
Our Solution: Pulsed TIG for 6061-T6 to preserve temper; MIG for 5052/5083 structural frames. Pre-weld cleaning and post-weld re-aging on request.
Magnesium Alloys — Inert Shielding & Ignition Prevention
Challenge: Highly reactive — oxidizes rapidly in air and can ignite if not properly shielded. Requires strict inert gas control.
Our Solution: TIG with high-purity argon shielding; controlled pre-heat to prevent cracking. We process magnesium on a project basis — contact our engineering team for feasibility assessment.
Copper & Alloys — High-Heat-Input Welding
Challenge: High thermal conductivity (even higher than aluminum) requires high heat input and preheat — difficult to achieve consistent fusion.
Our Solution: TIG (GTAW) with high preheat; ERCu or ERCuSi-A filler. Typical applications: electrical bus bars, heat exchangers, decorative parts.
Titanium & Alloys — Atmospheric Contamination Prevention
Challenge: Titanium reacts with oxygen, nitrogen, and hydrogen at temperatures above 400°C — causing embrittlement if not shielded.
Our Solution: Full inert gas shielding (trailing shield + purge gas); TIG welding only. Medical and aerospace programs with full MTR traceability.
Welding Materials & Base Metal Compatibility
Below are the 7 base metal groups we weld most frequently — with recommended process, filler metal, and post-weld treatment for each.
| Material | Grade Range | Recommended Process | Filler Metal | Post-Weld Treatment | Key Applications |
| Stainless Steel (Austenitic) | 304, 304L, 316, 316L, 321 | TIG (GTAW) / Pulsed TIG | ER308L (304), ER316L (316L) | Passivation ASTM A380; pickle paste for HAZ | Medical enclosures, food equipment, marine hardware |
| Stainless Steel (PH) | 17-4PH (AISI 630), 15-5PH | TIG (GTAW) | ER630 | Solution treat + H900 aging if required | Aerospace fasteners, surgical tools, valve bodies |
| Aluminum (Structural) | 5052, 5083, 6061-T6 | TIG (GTAW) / MIG (GMAW) | ER4043 (6061), ER5356 (5083) | Re-aging (T6) where strength critical | Aerospace panels, EV enclosures, structural frames |
| Carbon Steel (Mild) | 1008/1010 (AISI), A36 (ASTM), Q235 (GB) | MIG (GMAW) / Robotic MIG | ER70S-6 | Powder coat / zinc phosphate preparation | Machine frames, structural bases, heavy fabrication |
| Carbon Steel (High-Strength) | S420, S460 (EN), HSLA 340/420 | MIG (GMAW) – low hydrogen | ER80S-D2, ER90S-G | Controlled cool; PWHT on request | Automotive structural, heavy machinery |
| Galvanized Steel | DX51D+Z (EN), G90/G60 (ASTM A653) | MIG (GMAW) – zinc-tolerant params | ER70S-6 with adapted parameters | Touch-up zinc-rich paint at weld zone | HVAC, outdoor enclosures, construction |
| Copper Alloys | C11000 (ETP), C26000 (Brass) | TIG (GTAW) – high preheat | ERCu, ERCuSi-A | Annealing on request | Electrical bus bars, heat exchangers, decorative parts |
