Finding a sheet metal components parts manufacturer that genuinely supports PPAP is different from finding one that simply stamps metal. Many suppliers will say they can produce automotive parts; far fewer have the documentation systems, inspection equipment, and process discipline to back a part submission with real data. For OEMs and Tier suppliers, that difference decides whether a program launches on schedule or stalls in review.
PPAP, or Production Part Approval Process, is the standard procedure used across the automotive industry to confirm that a supplier's production process can consistently make parts that meet the customer's drawings and specifications. It is not a single test. It is a package of evidence gathered from the actual production line, covering tooling, materials, process, and inspection, submitted before mass production begins. When a customer asks for PPAP support, they are asking the manufacturer to prove, with documents and measurements, that the parts will be right the first time and stay right over the life of the program.
A typical PPAP submission pulls together several documents. The part submission warrant, or PSW, is the summary sheet that declares the part ready. Around it sit the process flow diagram, the PFMEA, the control plan, dimensional inspection results, and material certifications. Depending on the customer's requirements, this can also include capability studies, measurement system analysis, and first article inspection reports. The point is traceability: every critical dimension on the drawing should be traceable to a measurement, and every measurement to a documented method.
So what should a buyer look for when evaluating a sheet metal parts manufacturer for PPAP support? Start with the basics. Does the company build its own tooling? A manufacturer that designs and builds its own stamping dies controls the process from the start, which makes dimensional consistency far easier to achieve and document. Does it have the right equipment, such as progressive, transfer, and tandem dies for the parts you need? Can it handle the materials your program specifies, from multiphase steel to aluminum and stainless steel? And does it have inspection tooling of its own, such as checking fixtures, so that measurements are repeatable and not dependent on a single operator's judgment?
DIAN STAMPING, a China-based manufacturer in Linhai, Taizhou, Zhejiang Province, was built around exactly these requirements. Established in 2003, the company has more than 20 years of experience serving automotive OEMs and their suppliers, with customers including KIA, BYD, Toyota, Honda, Suzuki, and Geely, and exports to more than 10 countries. Its facility covers roughly 50,000 square meters, including a dedicated die workshop, and it employs around 110 people, about 35 of them die designers and technicians. The company operates as a factory rather than a trading company, which means the people who quote the job are the same people who build the dies and run the presses.
Across its four product lines, stamping dies, sheet metal parts, checking fixtures, and welding jigs, DIAN covers the full chain from tooling to finished assembly. Its die shop produces progressive, transfer, and tandem dies for medium and small stamping dies, with an annual capacity of roughly 2,000 sets. Its checking fixtures are built around GD&T-oriented inspection, giving customers a repeatable way to verify stamped parts on the production floor. Welding jigs support accurate, repeatable assembly. Parts span body-in-white, door systems, seating systems, instrument panels, fuel-tank systems, exhaust systems, clutch systems, and chassis systems.
On the quality side, DIAN runs an ISO 9001 quality management system and follows automotive manufacturing and quality practices aligned with IATF 16949. In practice, that means process documentation, inspection records, and traceability are part of the normal workflow, not a special request. For customers that need PPAP documentation, this foundation makes assembling the submission package a routine step rather than a scramble.
Getting started is straightforward. Send a 2D drawing, 3D data, or a physical sample, and the engineering team will review the part for manufacturability and respond with a quotation. Prototypes are available before production tooling is committed. Typical delivery runs 30 to 40 days for steel stamping dies and about 70 days for casting dies, depending on the project. Free metal samples can be arranged, with freight paid by the customer.
PPAP support is not a feature you bolt onto a stamping supplier; it is a measure of how the whole operation is run. For buyers who want a sheet metal components parts manufacturer that can back its parts with documentation, DIAN STAMPING is worth a conversation.