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The non-standard screw industry will test the products produced, such as special-shaped screws, non-standard screws and so on.After testing, it will find out where the product is not up to standard, so as to better improve its product.In this way, we can provide better products for customers and win the favor of users.
Testing fasteners for non-standard screws, appearance and quality requirements;Inspect nonstandard screws and electroplating.The thickness of the helix coating can be checked with micrometers, vernier calipers and plug gauges.Magnetic method magnetic method is used to measure the thickness of the coating.The microscopic method is called metallographic method. The etched fastener is put into a metallographic microscope with micrometer eyepiece for magnification to measure the thickness of coating on the section.Timed flow method.
The time-flow method USES a solution that dissolves the plating solution on a portion of the surface of the coating and calculates the thickness of the coating based on the time required to dissolve the portion of the coating.There are electroplating drip method, anode dissolution coulomb method and so on.Check adhesion strength of helix coating: there are many methods to evaluate adhesion of coating to base metal, usually as follows: friction polishing test;Drilling test;Scratch method;Bending test;Thermal shock test;Extrusion method.Corrosion resistance test of spiral coating of stainless steel: corrosion resistance test method: atmospheric explosion test;Neutral salt spray test (NSS test);ASS test, copper accelerated acetate spray test (CASS);And corrosion paste corrosion test (CORR test) and solution drop corrosion test;Dip test, inter dip corrosion test, etc.
Steel structural bolts are what we call high-strength bolts, and some friends like to call them high-strength bolt joints.It is also very convenient to install steel structural bolts, which can usually be solved with a wrench.However, some friends recently said they used some manufacturer's bolts and found that some bolts were locked.Non-standard fastener processing screw industry for the production of products will be tested
I think this problem is necessary.First of all, I think we need to carefully consider the strength grade when selecting steel structure bolts.Generally speaking, the steel structure bolt has several kinds of hardness, namely the strength grade, has 8-8 grade, still has 10.9 grade and so on.High magnitude of 12.9.Therefore, we need to understand the strength grade used when choosing to use steel structure bolts.For example, the tensile strength of screws and the safety load of nuts.It's a convenience.
In addition, the length of the steel structure screw must be selected to obtain the correct benefit by tightening the nut to show ZUI the preferred one or two pitch.
The second case results in bolt locking of the steel structure.I think it's a rough tooth or a foreign body.For example, some solder joints and other metal fragments are sandwiched between the teeth, which often results in steel.Structural bolts and nuts are locked.
Another point is that the force is too strong or the speed of the lock is too fast, so when installing the steel structure bolts, the nut needs to be tightened with a torque wrench or a socket wrench.These are also to avoid locking bolt problems.
There were also minor problems with the direction and Angle of the screws that led to the final locking of the steel structure bolts.