Solar mounting base bracket

Specifications

Product Specification Sheet
Product Name	Stamped and Bent Solar Mounting Base Bracket with Symmetric Side Flanges
Part No.	SMB-01
Category	Solar mounting brackets
Overview	One-piece stamped and press-brake formed base bracket for PV rail-to-purlin and post-base connections. A rectangular base plate is bent up on both sides into symmetric L-shaped flange ears with no weld seam, giving a compact, corrosion-resistant fastening point for outdoor solar arrays.
Version	V1.0 \| 2026-09-15
Material
Main material	Q235B carbon steel
Grade and standard	Q235B per GB/T 700-2006 （S235JR equivalent per EN 10025-2）
Alternative material	SUS 304 stainless steel per GB/T 3280; S355JR high-strength low-alloy steel
Raw material form and thickness	Flat sheet / coil, 4.0 mm （0.157 in） nominal thickness
Material certificate	EN 10204 3.1 mill certificate per heat number; 304 option supplied with GB/T 3280 3.1 certificate
Process
Blanking	Progressive-die stamping blanking from coil; optional CNC laser blanking for prototypes
Forming	Two 90° upward press-brake bends forming symmetric L-shaped flange ears （inner bend radius approx. 1.0 x t = 4 mm / 0.157 in）
Joining	No welding - one-piece monolithic construction, zero weld seam
Secondary operations	Punching of 1 central large hole, 4 base small holes and 4 flange holes; deburring and edge rounding
Surface pretreatment	Alkaline degreasing, acid pickling, water rinse and fluxing before galvanizing
Key process control points	Bend springback compensation, hole-to-bend-line distance, bend angle consistency, flange height uniformity
Surface treatment
Treatment method	Hot-dip galvanizing （HDG（ after forming; stainless 304 option supplied with passivated mill finish （2B）
Coating thickness	Average zinc layer >= 65 µm （0.0026 in）, local minimum >= 55 µm （0.0022 in）
Color and appearance	Matte silver-grey zinc spangle; uniform, no bare spot, no zinc dross, no pinhole
Standard and salt-spray requirement	HDG per GB/T 13912-2020 （ISO 1461 equivalent）; neutral salt spray （NSS） per GB/T 10125 / ISO 9227 >= 480 h without red rust
Surface roughness	Ra <= 12.5 µm on galvanized surface; Ra <= 3.2 µm on stainless 304 option
Pretreatment	Degreasing - pickling - rinsing - fluxing; no acid residue allowed before dipping
Tolerance
Overall profile tolerance	Overall length / width +/- 0.5 mm （+/- 0.020 in）
Hole diameter and position tolerance	Small holes Ø8 mm （0.315 in）+0.2/0 mm; central hole Ø45 mm （1.772 in） +0.3/0 mm; hole position +/- 0.3 mm （+/- 0.012 in）
Bend angle and bend radius tolerance	Bend angle 90° +/- 1°; inner bend radius 4 mm （0.157 in） +/- 0.5 mm
Weld position tolerance	Not applicable - no welding process on this part
Flatness and straightness	Base plate flatness <= 1.0 mm / 100 mm; flange straightness <= 0.8 mm over full height
Assembly fit tolerance	Flange slot width and bolt clearance designed for M8 （5/16 in） hardware with 1.0 mm total clearance
Dimension basis	Customer drawing / 3D model prevails; unspecified tolerances per GB/T 1804-m and ISO 2768-mK
Packaging
Surface protection	VCI anti-rust paper or PE film wrapping; no contact with bare ferrous material
Unit inner packaging	PE bag or kraft interlayer between every 20 pieces
Outer packaging	Carton on wooden pallet or pallet only, stretch film wrapped with edge protectors
Quantity, carton size and gross weight	400 pcs per pallet; pallet 1200 x 1000 x 800 mm （47.2 x 39.4 x 31.5 in）; gross weight approx. 260 kg
Marking and shipping marks	Part no., batch/heat no., quantity, net/gross weight, PO number, carton no.; marks per customer requirement
Container loading and stacking	Max stacking 4 pallets high; 20GP approx. 22 pallets / 40HQ approx. 48 pallets
Storage and transport	Store in dry, ventilated warehouse, off ground on pallets; keep dry during transport
Quality control
Incoming inspection	Mill certificate check, thickness measurement, chemical composition spot check, surface defect visual check
First article approval	Full-dimension first article report （FAR）with 3 pcs retained, approved before mass run
In-process inspection frequency	Every 2 hours or every 500 pcs, whichever comes first; key dimensions recorded in SPC chart
Final and pre-shipment inspection	AQL 1.0 for critical dimensions, AQL 2.5 for appearance; coating thickness gauge on each pallet
Inspection equipment	CMM, digital caliper, height gauge, protractor, coating thickness gauge, salt-spray chamber
Records and reports	Inspection records retained 3 years; FAR, SPC chart, coating report, COC / mill certificate issued per shipment
Nonconforming product handling	Segregated, red-tagged and reviewed by MRB; rework / re-galvanizing / scrap decision documented
Quality system and certification	ISO 9001:2015 certified factory; PPAP / 8D report support on request
Notes	The parameters listed in the table are standard values based on product photographs and our factory's standard manufacturing processes. For items marked as "Recommended Values," as well as all dimensions, materials, and tolerances, the final specifications shall be determined by the customer's drawings (2D/3D), technical agreements, and the results of the first-article inspection.
Drawing Format	3D: .step / .stp / .igs 2D: .dxf / .dwg / .pdf
For Quotation	Drawing + material + surface treatment + quantity + tolerance requirement