Service HotlineThe produced screws, due to unreasonable production aspects, are likely to cause quality problems in the screws. During production, many screw quality problems may be found upon delivery. Let's talk about the quality problems often encountered by screws and the reasons for the quality problems, and finally put forward some solutions. 1. The head of the screw is deformed and the head is crooked. The possible reasons are the poor installation of the first punch of the screw die and the improper adjustment of the machine. 2. The head of the screw is not round. The reason is that the selection of the first punch of the screw mold is improper or the first punch is not full enough. 3. The screw has burrs or burrs. The reason is the poor forming of one punch, mainly caused by too large gap between punch and die hole or too short punch. 4. The screw head is cracked and the screw head is cracked. The reason may be that there is a problem with the quality of the screw wire itself, so before the screw wire is headed, the quality department must check it and use the potion. Especially the stainless steel screw wire, it is necessary to check that it is stainless steel 201 and that is stainless steel 304. It is also possible that a die is used incorrectly (such as a die with a hexagonal washer head for a pan head), and the viscosity of the lubricating oil fails. For the problem of the screw head, you can read the article written by Manager Zhu above - high-strength screw fracture or head crack detection. In this article, some problems encountered by the screw head and how to detect the screw head problem are clearly introduced [4]. The common quality reasons for screws are of course more than the above, this is only part of it. There are other quality issues, then Manager Zhu will talk about it. The above screw quality reasons are for reference. If you encounter these problems, you can try the solutions proposed.
Although there are many types of self-tapping locking screws, they all have the following main characteristics: (1) Generally, they are made of carburized steel (accounting for 99% of the total products). Also available in stainless steel or non-ferrous metals. (2) The product must be heat treated. Carbon steel self-tapping screws must be carburized, and stainless steel self-tapping screws must be solution hardened. In order to make the self-tapping screw meet the mechanical properties and performance required by the standard. (3) The product has high surface hardness and good core toughness. That is, inner softness and outer rigidity. This is a major feature of the performance requirements of self-tapping screws. If the surface hardness is low, it cannot be screwed into the matrix; if the toughness of the core is poor, it will break as soon as it is screwed, and it cannot be used. Therefore, inner softness and outer rigidity are the requirements for self-tapping screws to meet the performance requirements. (4) The surface of the product needs surface protection treatment, generally electroplating treatment. Some product surfaces require phosphate treatment (phosphating). Such as: wall panel self-tapping screws are mostly phosphating. (5) It is produced by cold heading process. It is recommended to use high-speed cold heading machine and high-speed thread rolling machine or high-speed planetary thread rolling machine to ensure product quality. The self-tapping screw produced in this way has a well formed head and high thread quality.
On the surface of the mounting hole on the connector, a 90-degree conical socket is machined, and the head of the flat machine screw is in the socket and is flush with the surface of the connector. Flat machine screws are also used in some occasions with semi-circle head flat machine screws, which are more beautiful and are used for places where a little protrusion is allowed on the surface. Screws play the role of connecting two or more objects and are an indispensable necessity in daily life or industrial manufacturing. There are countersunk head bolts (with grooves) and countersunk head bolts (with tenon).
According to relevant standards, the performance grades of carbon steel and alloy steel bolts are divided into more than 10 grades such as 3.6, 4.6, 4.8, 5.6, 6.8, 8.8, 9.8, 10.9, 12.9, etc. Among them, the bolts of grade 8.8 and above are made of low-carbon alloy steel or medium Carbon steel and heat treatment (quenching, tempering) are generally called high-strength bolts, and the rest are generally called ordinary bolts. The bolt performance grade label consists of two parts of numbers, which represent the nominal tensile strength value and yield ratio of the bolt material respectively. Stainless steel bolts are divided into A1-50, A1-70, A1-80, A2-50, A2-70, A2-80, A3-50, A3-70, A3-80, A4-50, A4-70, A4-80, A5-50, A5-70, A5-80, C1-50, C1-70, C1-110, C4-50, C4-70, C3-80, F1-45, F1- 60. The first letter and number represent the stainless steel group, and the second and third numbers represent 1/10 of the tensile strength. [2]
In order to solve this technical problem, Yueluo Company provides an adjusting nut, which includes a bearing unit, a thrust washer, an adjusting nut and a snap ring. The inside of the adjusting nut is an internal thread structure, and one end of the internal thread structure is provided with Ring groove, the snap ring is pressed into the ring groove with interference, and is rigidly connected with the adjusting nut without relative movement; the bearing unit is supported on the shaft, and the thrust washer is in plane fit with the bearing unit; the adjusting nut and the shaft are threadedly connected , Fit with the thrust washer plane, the inner diameter of the snap ring and the thread of the shaft are in interference fit.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: welded square nuts, 8-grade fine pitch black hexagon nuts, full-tooth external hexagon screws and nuts, black pin shaft GB882 pins and other products, we can provide You have the right fastener solution for you.
