A high-quality metal stamping manufacturer is a prerequisite for success. However, many people don’t know how to choose the right one. It will be much easier to select a qualified metal stamping manufacturer if you understand some basic information about metal stamping and what can affect your business process. Here is some advice on how to choose a high quality China-based metal stamping manufacturer.
What is Metal Stamping?
There are two ways to process metal parts—machining and metal stamping. Each has unique characteristics and applications. Metal stamping is the best choice for mass production because of its low cost and high productivity. So if you are looking for a qualified metal stamping manufacturer in China, understand the characteristics of metal stamping.
There are two significant types of metal stampings—progressive die and transfer die. The advantages of progressive die metal stamping area short production cycle and high output compared to transfer die metal stampings.
What Are the Factors Affecting Metal Stamping Quality?
If you consider choosing a high-quality China-based metal stamping manufacturer, consider the following factors. Otherwise, your parts will have quality issues.
1. The Material of Dies
The material of dies is one of the most critical factors which can affect metal stamping quality. Good machining starts with suitable tools, so a qualified manufacturer should pay much attention to die material, heat treatment, and other issues.
The material of the stamping dies on the type of product and its features. Commonly, ordinary steel is used for stampings with thin walls and a large surface area. But if you need to produce a complicated part with high precision and a thin wall, P20 steel should be used.
The accuracy of die sets determines how smooth your parts will come out and what kind of problem they will have after forming processing. Better accuracy can improve metal stamping quality significantly.
When choosing a China-based metal stamping manufacturer, it is essential to check whether their machines are equipped with advanced inspection equipment, such as laser measurement tools, to guarantee the accuracy of die sets.
Every good metal stamping manufacturer should recheck the dimensions of every die set after heat treatment and surface grinding for error, at least once or twice per year, to ensure product quality.
3. The Number of Stamping Shots and Punches
How many times a part is significantly stamped affects its tolerances, so it is essential to pay attention to this issue when choosing a China-based high-quality metal stamping manufacturer.
For thin-walled parts, a few shots after the forming process are best because fewer secondary operations will be needed and you can avoid stamped marks on your products. However, multiple punches are a great choice if used to highlight your product’s aesthetic appearance.
Note that too many stampings can lead to deformation and reduce over all quality.
4. Surface Roughness
Surface roughness is a critical factor that determines whether your product is smooth and beautiful post forming.
High-quality stamping surfaces should be a mirror or satin finish. For many thin-walled parts, a single grinding operation suffices to improve surface quality. Multi-layer stamping products with multiple punches can require as many as three times the polishing prior to heat treatment.
5. Heat Treatment
Heat treatment is usually carried out post-stamping.
High-temperature tempering, quenching, and normalizing temper processing are common heat treatments for progressive die metal stampings in China. After heat treatment, your parts will be stronger with better performance.
Heat treatment can improve metal stamping quality significantly and help your parts resist deformation, stress, and cracking.
However, too many heat treatments can quickly reduce the accuracy of your product, resulting in poor surface finish and deformation.
6. The Surface Treatment
Surface treatments for progressive die metal stamping differ from the surface treatments for transfer die metal stampings.
Rust-proof oil or black oxide will be applied on the surface of high-quality progressive die-stamped components after heat treatment. But if your products need greater aesthetic appeal, consider finish polishing, carried out by experienced workers.
Surface treatments improve metal stamping quality significantly and result in improved performance.
Progressive die metal stampings are usually transferred to the machining department post stamping.
High-quality progressive die-stamped components might pass a series of machine turning and other processes before the finished product is completed. Each is essential to ensure high-quality products with accuracy, smooth surfaces, a beautiful appearance, and enhanced performance.
8. Parts Inspection
When choosing a professional China-based metal stamping manufacturer, it’s necessary to check whether they have the required equipment, such as coordinated measuring machines (CMM) and ultrasonic testing (UT), to ensure product quality.
It’s better to choose a manufacturer with an in-house laboratory that can do hardness testing once a week on die sets and finished products. This helps you avoid some unexpected issues after stamping manufacturing.
There are two types of inspections in the China-based metal stamping industry, 1) random review, which machine operators do during the manufacturing process, and 2), a one-hundred percent final inspection before packing that only highly qualified workers can do.
9. Delivery Date
To meet an urgent demand, many metal stamping manufacturers can not deliver numerous parts on time because of production workload differences.
When you need high-quality stamped components, ask your China-based supplier about their capacity and how long they take to make the product after you place the order. If they tell you, they will provide a quote within 24 hours of your inquiry, the supplier can be considered professional.
10. Marking and Painting
Marking and painting are crucial processes that make your final product look its best with the brand name, model number, and/or other descriptive information.
High-quality metal stampers are equipped with advanced, 3D laser marking equipment, which offers precision markings and high processing speeds. These are automated machines which can reduce labor costs for these procedures.
However, they are also costly compared to conventional marking methods, so pay attention when you choose your manufacturer.
11. Quality Control Processes
Quality control is always one of the most important factors determining your stampings meet customer requirements.
High-quality manufacturers should have a quality control staff responsible for testing their products during every procedure, including heat treatment.
Their test procedures should be strictly defined according to international or national specifications, which you need to provide before production. If possible, consider ISO system certification to ensure all your procedures are controlled under qualified management.
12. Packaging and Transportation
Proper packaging and transportation can reduce the risk of damage to stamped parts, especially large and/or heavy components.
Ask your stamping manufacturer for detailed information about their packaging and transportation options before production. Also, provide samples of similar products and test the packaging and transport if possible.
13. The Price
Price is a factor that you can not ignore when choosing a China-based metal stamping manufacturer, but that doesn’t mean the lowest price is the best choice.
Quality and service levels are a function of price, so don’t make the mistake of making your choice solelybased on cost. Make comparisons based on both price and service level before choosing.
14. Profit Margins
Profit margins are something few will discuss, but they are an essential factor. Before deciding which metal stamping manufacturer to choose, consider your final profit margins and determine if the prices offered allow you the profit margin required.
If not, you think about lower production costs or even higher productivity from high-quality metal stamping manufacturers.
The best way to determine reliability is to through feedback (word-of-mouth) from other businesses that have used their services. You can also take advantage of trade platforms that offer supplier evaluations for their members.
16. After-the-Sale Services
You must pay attention to the after-the-sale services provided by your choice of a stamping manufacturer. If there is a problem with your products, the manufacturer should provide after-the-sale service immediately, according to your requirements, including both re-manufacture and repair.
Professional metal manufacturing stampers should have a machine maintenance department and spare parts stored for any unexpected situation arising during production. Even if it takes a longer time, they should keep close contact with you.
If you find that your China-based metal stamping manufacturer only offers tool maintenance but no spare parts, then they can’t provide after-the-sale service for your product.
Choosing a high-quality China-based metal stamping manufacturer is a long and detailed procedure that involves multiple factors to be evaluated before you sign the contract.
Since there are many issues to consider when you choose a high-quality China-based metal stamping manufacturer, it is crucial to get professional advice before placing an order.