What is the tolerance range of precision screws?
What is the tolerance range of precision screws?
Guangdong Yueluo Hardware Industry Co., Ltd. discloses a rivetless rivet, which includes a nail body and a mandrel, wherein one end of the nail body is provided with a nail body brim, and the nail body brim is provided with a nail body. A coaxial counterbore, the nail body is provided with a through hole coaxial with the nail body, the counterbore is communicated with the through hole and its diameter is larger than the diameter of the through hole, and one end of the mandrel is provided with a mandrel cap The other end is provided with a clamp head, and the end is provided with an elastic groove for retracting the clamp head inward or opening it outward. The clamping head on the core is clamped on the boss formed by the countersunk hole and the through hole. The above-mentioned rivet-free rivet is not only simple, compact and reasonable in structure; riveting is simple and does not require professional tools and equipment; and it is easy to disassemble after riveting, can be reused, has a wide range of applications, and is reliable and stable in connection.
In general, the size, mechanical properties and working performance requirements of self-tapping screws have the following standards: 1. Self-tapping screw size standard ASME B18.6.3 2010 standard not only introduces the dimensions of slotted and cross-recessed self-tapping screws and metal drive screws, but also includes the mechanical properties and work performance requirements of carbon steel self-tapping screws. The appendix gives instructions for measuring the various dimensions and application guidance on clamping lengths and test apertures. 2. Self-tapping screw performance standards (including mechanical properties and work performance): (1) SAE J933: Introduces the mechanical performance and work performance requirements of carbon steel ordinary self-tapping screws and white-cut self-tapping screws. The requirements for selection of raw materials, heat treatment, depth of carburized layer, surface hardness, and core hardness are further specified. (2) SAE J81: The mechanical properties and working performance of self-extrusion self-tapping screws (self-tapping locking screws) are introduced. (3) SAE J78: The mechanical properties and working properties of self-drilling and self-tapping screws are introduced. (4) IFl-113: The mechanical properties and working properties of self-drilling and self-tapping screws are introduced. (5) ASTM C1513: Introduces the mechanical properties and performance requirements of carbon steel self-tapping screws. For other special types of self-tapping screws, there is no corresponding national or industrial standard, and no data for self-tapping screws made of other metal materials other than carbon steel have been recognized. For technical data on these self-tapping screws, you can check with the manufacturer.
Two combination screws are mostly used for the connection between thin metal plates, and play a connecting role. When connecting, first make a threaded bottom hole for the connected piece, and then screw the combination screw into the threaded bottom hole of the connected piece. Since the threaded surface of the combination screw has high hardness, the inner thread can be tapped in the threaded bottom hole of the connected piece to form a connection.
For the detection of the shear force of the elastic cylindrical pin, the method and the tooling are marked, but the tooling is only a means to be used on the test bench, and the process of embedding the cylindrical pin into the tooling is a more difficult process. Generally, it is used to place the tooling on a plane, a vise, a simple V-shaped, and a simple U-shaped fixture. Originally, the elastic cylindrical pin was detected by hand or pliers to hold the cylindrical pin and align the pin with the outer cylinder of the tooling. Use a hammer to smash the shear holes, and adjust the concentricity of the inner and outer cylinders of the shear holes of the tooling from time to time. The limitations, dangers and difficulties of this assembly method are relatively large, often testing a set of cylindrical pins, which takes a lot of time and is difficult for lesbians to complete.
The above content is uploaded by Yueluo or the Internet. If there is any copyright issue, please contact [email protected].
