Look at the processing plant: see if it has a specific production and manufacturing industrial plant, sound production and manufacturing equipment, technical professional technical elite team and its strict testing machinery and equipment. This is very important, good is their own door-to-door service visits, to prevent some shell companies from being blinded, suffered losses.

2. Look at the qualification certificate: see whether it has up to standard production and manufacturing qualification certificate, enterprise business license and ISO enterprise qualification certificate, etc. this kind of stainless steel rivet is the reasonable evidence to prove the overall strength of the enterprise.

3. Looking at the commodities, we must point out the technical and professional methods here. We will show you some application methods for reference only

① According to the appearance:

A. Does the top of your head shine

B. Are there cracks, cracks, scratches on the top of your head

C. Head is round mouth, umbrella head, small flat head, or frosted.

D. Is there a protuberance at the root due to the crack of the main mode

E. Is the wound leveled

F. Is the rivet bar in the middle of the top of the head, otherwise it will bend and bend

G. Is the rivet bar scratched and uneven

② Whether the specifications of each position are in line with the production and manufacturing regulations. The important index values such as the diameter from the beginning, the diameter of the rod, the length of the rod to the depth of the triple lock rivet must be measured to more than two or three times, and 10-20 pieces of samples should be inspected each time. In the case of accurate measurement, we must adopt the standard size, standard precise measurement attitude, so as to ensure the effectiveness of accurate measurement.