Find Reliable Metal Stamping Manufacturers in China

Looking to source metal stamping products from a China manufacturer? Whether you are new to China sourcing or Amazon selling business, it is important to know the multiple facets involved in sourcing stamped metal products from China. This includes knowing the basics of the process, tools and technology used in design and manufacturing as well as finding the right manufacturer in China which is possible after negotiating a good price and ensuring the supplier understands your technical specifications.

Although this sounds complex, sourcing stamped products from China can be seamless and easy with the support from a China sourcing agent who specializes in this type of manufacturing.

What is metal stamping?

It is a process of manufacturing where flat metal sheets are converted into specific shapes with the application of high amounts of pressure. As a complex process, it involves a number of techniques and steps such as punching, blanking, embossing, coining, flanging, piercing and bending. The high-speed and low-cost manufacturing process is used to make a large number of identical metal components.

The process can involve a single stage where the desired shape of the part is produced with each stroke of the stamping press. It can also involve a series of stages where progressive dies are used to progressively shape the component. While the stamping process is typically performed using sheet metal, other flat materials can also be shaped using this technique.

Known also as ‘pressing’ or a cold-forming process, flat sheet metal is transformed into the desired part or component with the help of dies and stamping presses. The sheet metal pieces, known as blanks, are fed to the stamping press that has a tool and die surface which creates the required shape from the blanks.

Stamping refers to the metal forming process in which the manufacturer uses custom tooling and stamping techniques to make parts according to the customer’s specifications.

The process is utilized by multiple industries for meeting the demand for high volume production and to make identical precision parts. 

The process

Metal stamping, known also as pressing, is a process where flat sheet metal in the form of blanks or coils are placed in the stamping press. In the press, a tool and die surface the tool and die on the press give the desired shape to the metal.

Before shaping the metal in the press, the tooling has to be custom designed as per the product specifications using computer aided design and manufacturing or CAD/CAM technology. These designs need to be precise to make sure that the punch and bend retain proper clearance as well as optimal part quality. A 3D model of a tool can have hundreds of parts, making the design process complex and intricate.

After the custom tool is designed through CAD/CAM, the manufacturer uses various manufacturing methods including machining, wire EDM and grinding to complete the stamped metal parts production.

The various processes used include:

• Blanking - Blanking involves cutting a rough shape or outline of the desired product. Experienced and reputable manufacturers in China focus on minimizing burr or rough edges on the metal at this stage. Burrs can drive up the lead time and the cost of making the part. The hole diameter, which is the spacing between hole and edge as well as geometry, is determined in this stage. The workpiece or blank is removed after it is shaped from the sheet metal, giving the desired blank.
• Punching - This process involves removal of scrap material from the workpiece as opposed to blanking where the workpiece is removed from the sheet metal.
• Bending - When bends such as L, U or V shapes are required in the part, the manufacturer uses bending techniques to create the shapes.
• Flanging - In this, specialized flanging machinery or dies are used to introduce flange or flare in the part. Flanging is also a type of bending where a ‘flange’ is created which is different from bends as the dimension of the bends are smaller than the part. Flanging gives a better finished appearance and provides edge strengthening and rigidity.
• Coining - In this the workpiece is positioned between the die and press. The metal is penetrated into by the tip of the punch  to create accurate and repeatable bends.
• Embossing - Embossing creates the desired raised or recessed design in the metal. 

The machines can go above just stamping and can punch, cut, cast, as well as shape metal sheets. Machines can be numerically controlled by computer or programmed to offer repeatability and high precision of each stamped piece.

Types of metals used

The metals used depend on the application of the finished product. Different metals have their own unique qualities that makes each metal the perfect choice for the specific product. In some cases, for certain products, base common metals may be processed into alloys to achieve an optimum strength or other properties of the end product.

Many manufacturers in China have expertise in stamping various metals and materials including:

• Aluminum
• Brass
• Steel
• Stainless Steel
• Nickel
• Beryllium Copper
• Phosphor Bronze
• Phenolic
• Monel
• Plastics
• Fiber

Some of the metals used in different applications and industries include:

• Medical: Beryllium Copper
• Appliances: Copper
• Automotive: Custom phosphor bronze, steel or phosphor bronze
• Electrical: Brass

Some manufacturers may also provide plating of the above metals with gold, silver, nickel, bright zinc and tin.

Applications

Metal stamping is widely used across industries to make many components such as hinges, frames, pins, springs, lead frames, contacts and terminals. These products are used for multiple applications in home electronics, appliances, utensils, telecommunications, construction, automotives and agriculture equipment.

The applications extend to 3D designs/letterings, surface engraving and other decorative finishes.

Stamped metal parts are also used in the computers found in medical devices. You will find various applications in different industries such as:

• Aerospace products - Latches, fastener type components, exhaust system components
• Agriculture - Housing components, hinges and frames
• Appliances - handles, latches and internal components
• Automotive parts - Exhaust system components, brackets, hinges, hitches.
• Commercial/Residential - Clamps, garage door components, electrical covers, handles
• Construction - Braces, floor plates, connectors
• Electronics - Circuit board components, fittings, hardware parts, chassis, frames for computer equipment
• Engine brackets
• HVAC - Separators, brackets, baffles, covers
• Lawn equipment parts
• Consumer products - packaging parts for premium skincare products
• Lighting equipment parts
• Marine - fittings, brackets, couplings, connectors, enclosures, frames
• Medical - products for portable medical devices, medical computer stand parts, instrument connectors, trays
• Plumbing - Straps, hooks, clamps, hangers, safety plates,
• Power tools

Metal stamping types

The main techniques used include:

• Deep drawing
• Progressive die stamping
• Four slide stamping 

Deep draw stamping: Deep draw stamping is a techniques where the machine pulls the sheet metal blank into the die through the punch to create the desired shape.  This technique is called ‘deep drawing’ as the drawn part’s depth exceeds its diameter. This technique is suitable for making components which require a range of diameters. As a cost effective technique compared to turning processes where more of raw materials are consumed, deep drawing finds wide applications including:

• Aircraft parts
• Automotive components
• Utensils and cookware
• Electronic relays

Progressive die stamping- This is one of the most widely used stamping processes. Many traditional techniques could only perform a single action at a time which would mean a different tool is required for each operation to produce the finished product. This leads to long turnaround times as well as high labor costs. The process was also not suitable for creating tight tolerance or intricate parts.

Progressive die stamping involves passing the sheet metal into a series of workstations. Each die in the series can bend, cut, punch, emboss, coin, draw or shave the metal depending on the specifications. Based on the complexity of components, the sheet metal may require one step or may go through forty steps.

Progressive stamping yields many benefits including:

• Faster production
• Efficiency of processes
• Cost-effectiveness of manufacturing
• Simultaneous stamping shapes can be created
• Quick set up process where one setup is needed to make completed parts
• Complex geometry and intricate parts can be created using the die stations in progressive stamping technique.
• Precision - Increased precision is guaranteed in this technique
• High repeatability as the tools used in progressive stamping are hard-tooled and can bear the high volume runs without degrading, that in turn ensures high quality of finished products.

Progressive die stamping is suitable for a wide range of metals including:

• Aluminum
• Copper
• Inconel
• Steel
• Stainless steel
• Noble metals
• Brass
• Coated Metals
• Titanium

Four-Slide stamping- Fourslide stamping or multi-slide stamping is commonly used to make complex parts that have multiple twists or bends. The die features  horizontal alignment as well as four different slides. This means that four tools are simultaneously used to shape the part.

Fourslide metal stamping confers several advantages as compared to traditional press stamping, making this technique an ideal choice for various applications. The main advantages of four slide stamping include more flexibility in design changes as well as versatility to create complex parts.

Four different tools can be attached to the four slides to simultaneously achieve multiple bends. The shaft in each tool bends the part quickly as the material is fed into the tool.

Transfer die stamping- This is similar to progressive die stamping except that the material to be shaped is transferred to stamping stations with conveyor belts or other mechanical transport systems.

Where can you find metal stamping manufacturers in China?

Many Amazon sellers start their search for manufacturers on Alibaba.com, which is the biggest marketplace in China. According to the search results displayed on Alibaba.com for stamping manufacturers, there are about 33,580 stamped products while the top region or country for stamped parts suppliers is China.

Made in China and Global Sources are other marketplaces to find stamped metal parts suppliers and manufacturers.  For bulk sourcing, DHGate can be useful where two million sellers are listed apart from guaranteed refunds and escrow protection. You can also visit the trade fairs and conventions such as the one organized by Hong Kong Trade Development Council as well as the Canton Fair.

The Canton Fair is the biggest trade fair in China where virtually all types of industrial products ranging from automotive to consumer goods, electronics and sports goods are featured. The Yiwu commodities fair and ECF (East China Import and Export Commodity Fair) are the other trade fairs that you can attend.

Although there are many trade fairs and marketplaces, there is also the chance of you getting deceived by scammers on these sites and fairs. Looking for a genuine, reputable and reliable metal stamping manufacturer in China can be tricky and involves time, effort and patience- particularly when you are a business that is new to the Amazon selling platform.

How can a sourcing agent help you find the best metal stamping manufacturer in China?

When you want to source stamped metal parts from China, there are many factors that you need to be aware of. One of the most crucial aspects you need to be well versed with relates to the basics of metal stamping and involves the techniques, steps and technology used. Many manufacturers in China use the latest CAD/CAM engineering technology to make stamped metal products while many are also ISO certified.

While you can check the website of each manufacturer and ask for documents, licenses and ISO certification, actual proof from the supplier acquired by inspecting the factory on ground is the only way to know if the supplier is genuine and if they have the technical capabilities.

Working with a China sourcing agent who specializes in this type of manufacturing gives you multiple advantages. While the agent can communicate well with suppliers in the local language, they are typically well versed with the techniques, tools used and the processes involved. They can visit the factory in person, do an audit while vetting the supplier before they recommend a manufacturer to you. They will also act as a go-between in case of a dispute or an unreasonable delay in delivery and can quickly work out alternate arrangements.

A specialist China sourcing agent who knows the processes and techniques helps ensure that the stamped metal products are manufactured to the desired, precise technical specifications. They will also inspect any raw materials - in this case, the quality of metals used.

Consulting a China sourcing agent can also help you build a strong, long term relationship with the right Chinese suppliers which ensures your business continues to prosper as an Amazon seller.  They can also negotiate the best deals for you keeping in mind the order size, technical details and the intended use of the product.

Sourcing Allies is a team of expert China sourcing agents that has helped western customers manufacture and source products from low-cost regions since 2006.

For more on China sourcing visit our website or write to us at info@sourcingallies.com.