Spring screws are mostly composed of jackets, guide sleeves, screws and springs. The sheath is the head of the spring screw, which is generally knurled and suitable for hand screwing. The guide sleeve is mainly used for riveting with the panel, including expansion riveting and pressure riveting. The sheath, the guide sleeve and the spring form an elastic combination, but the screw has no elasticity. Loose screws are widely used in cabinets, cabinets and box panels.
Why is it called PEM spring screw? It is because all the spring screws we come into contact with are produced and used according to the standards of PEM company in the United States, and there is no national standard to follow. I don't know when it is called PEM spring screw.
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