Quality control can be defined as “part of quality management focused on fulfilling quality requirements.” While quality assurance relates to how a process is performed or how a product is made, quality control is more the inspection aspect of quality management.Inspection is a major component of quality control, where physical product is examined visually.
A quality control inspection is an activity of checking quality of any product, such as measuring, checking, examining, testing or gauging one or more characteristics of a product and comparing the results with specified requirements in order to establish whether conformity is achieved for each characteristic. The quality inspector usually follows a pre-established checklist that is based on the product specifications. Inspected products can be the components (raw materials) used for production, semi-finished goods, or (most often) finished goods before shipment to a customer.
Why you need a quality control inspection service in China ?
To answer this question I can share an old story happened to our UK client years ago. He lost more than 120000 USD due to the quality issue in 2011. He placed an order of fitness equipment with a small factory in Yongkang, Zhejiang province. He purchased a sample and confirmed the quality before placing the order, however, the factory used slightly cheaper raw materials to reduce the costs in China during the massive production after the customer placed the order. And unfortunately the customer did not conduct any quality control inspection before loading in China, when he received the defective goods in UK, he found the problem and his end customers rejected the goods, what’s more, when he called the supplier for a solution, the supplier did not admit anything as he could not offer enough evidence.
This is a lesson for every importer and this is the main reason why you have to inspect your shipment first before loading in China for any large orders. Only by inspecting your shipment of goods before it leaves your supplier’s factory can you identify and address any quality issues before it’s too late. With the quality control inspection services, you can well control the quality of your product before production, during-production and before loading. Managing product quality with QC inspection lowers your risk of product returns, unhappy customers and many other costly and avoidable problems
How many types of quality control inspection ?
In case QC inspection is so important, so when shall we conduct the QC inspection? To answer this question, you have to understand the types of QC inspection first
Generally speaking there are 5 types of QC inspection services worldwide, that is:
PPI – Pre-Production Inspection
FAI – First Article Inspection
DPI – During Production Inspection
PSI — Pre-Shipment Inspection
CLL–Container Loading Inspection
but in China customers focus on following three main types of inspection in quality control:
PPI – Pre-Production Inspection
DPI – During Production Inspection
PSI — Pre-Shipment Inspection
Here are the details:
PPI- Pre-Production Inspection
The Pre-Production Inspection (PPI) is a type of quality control inspection conducted before the production process begins to assess the quantity and quality of the raw materials and components, and whether they are in conformity with product specifications. This service is important for large orders in China because some unreliable suppliers may try to use cheaper raw materials and components to save costs during massive production.
A typical PPI inspection checklist includes, but is not limited to:
Verifying the raw materials and their conditions.
Inspecting planned storage for your products.
Inspecting a supplier’s production readiness and quality plan
Inspecting the function, size, and measurement of raw materials and other components
Making the required reliability and safety tests
Making sure your specifications and sourcing requirements are correctly understood by the factory
Preventing any potential flaws and failure in the mass production
DPI — During-Production Inspection
During Production Inspection (DPI) or otherwise known as DUPRO, is a quality control inspection conducted while production is underway, and is especially good for products that are in continuous production, that have strict requirements for on-time shipments. The During-Production QC Inspection is mainly an inspection of semi-products, stock of raw materials, production process, package requirements, workmanship etc during the production of your order in China.
A during production inspection takes place once 20-50% of your product run has been completed and packed. During a DPI inspection, a quality control inspector will inspect the completed product to ensure that all processes are being followed to the agreed standard. They’ll also look to identify any product deviations or issues early in the manufacturing process.
A typical DPI inspection checklist includes, but is not limited to:
Verifying the supplier follows the requested process and material specifications
Verifying the production and quality plan
Inspecting storage conditions
Inspecting packaging, labeling, and barcodes
Conducting reliability and safety tests
Inspecting semi-finished products
DPI inspections are useful as a quality assurance measure as it ensures that the quality of the products in production is the same as the one you received as a sample. It also gives you chance to make any necessary adjustments and corrections before the production run has ended, which can save you valuable time and money. If defects have been identified, knowing the percentage of finished products with defects also ensures that you have time to plan for them before they are shipped to you.
PSI — Pre-shipment QC Inspection
The Pre-shipment QC Inspection is an inspection of all the finished products, documents, package, shipping marks, quantity etc of your order at the factory. This service shall be performed when the order is 80 -100% completed.This inspection is conducted on finished products when at least 80% of the order has been packed for shipping. This inspection is done according to standard Acceptable Quality Limits (AQL) specs for the product.
A typical PSI inspection checklist includes, but is not limited to:
Verifying the safety and function of manufactured products
Verifying the quality of products
Verifying the order has been produced to the standards set out in the purchase contract
Inspecting the product packing, labeling, and shipping marks etc
Checking the order quantity and the documents related
A PSI inspection makes sure that the supplier has manufactured your products to your specifications and packed them as required by your purchase contract. PSI inspection is the most popular and important one as you can reduce the risk of receiving defective items.
How to select a right quality control inspection service company in China ?
There are tens of hundreds of inspection service companies here in China. How to select a right QC inspection service partner in China ? Here are my tips:
If you are from a top brand and if you are rich enough, you can simply work with the well-known inspection service brands like SGS, BV, ITS etc. They all have branches in China and they offer professional QC inspection and testing services as well. Here are their official websites:
CCIC: www.ccic.com
ITS — www.intertek.com
SGS — www.sgs.com
BV — https://group.bureauveritas.com
TUV — www.tuv.com
UL — https://china.ul.com/
If you from a small-mid company and if you’d like to save more time and cost, you can work with a local inspection service company in China. When you search a factory audit service online, you will find out hundreds of QC inspection service providers in China. Here are my experience in selecting a right inspection service partner:
1.Qualifications
Ask them for their business license and check out their basic qualifications in China, say, business scope.
2.Service quality
Ask them for their client information, call their current clients for reference to check their service quality.
3.Quotation
Ask at least three service companies for quotation, do not choose the highest one or the cheapest one as low cost does not mean high service quality in China, try to choose a right one based on your budget.
4.Location
Choose a right service company who is nearer to your supplier in order to save more travel cost and time.
