What is the function of a double-headed bolt? Why choose a double-headed bolt?

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03 Main Uses 1. Used for large-scale equipment where accessories need to be installed, such as sight glasses, mechanical seal seats, gearbox frames, etc. This is where double-headed bolts come in use: one end of the bolt is screwed into the main body, and after the accessory is installed, a nut is placed on the other end. Since the accessory is often removed, its threads can wear out or get damaged; using double-headed bolts makes it very convenient to replace them. 2. Double-ended bolts are used when the thickness of the connecting body is considerable and the bolt length is very long. 3. Used for connecting thick plates and in situations where hex bolt connections are not feasible, such as concrete roof trusses, roof beam suspension units, and single-track beam hangers. 04 Purpose of anti-loosening: In practical applications, external loads such as vibration, changes in conditions, and high-temperature creep of materials can lead to a reduction in friction force. At certain moments, the normal pressure between the threaded components disappears, resulting in zero friction force; this causes the threaded connection to loosen. If this situation repeats itself, the threaded connection will eventually become loose and fail. Therefore, anti-loosening measures must be taken; otherwise, it will affect normal operation and lead to accidents. 05 Surface Treatment: Double-headed bolts generally require surface treatment. There are many types of surface treatments for bolts; the most commonly used ones include electroplating, blackening, oxidation, phosphating, and non-electrolytic zinc coating. However, electroplated fasteners account for a large proportion in the actual use of fasteners. It is particularly widely used in industries and fields such as automobiles, tractors, home appliances, instruments, aerospace, and communications. However, for threaded fasteners, during use it is required not only that they possess a certain level of corrosion resistance, but also that the interchangeability of the threads be ensured; this can also be referred to as thread fit here. To simultaneously meet the dual performance requirements of \"corrosion resistance\" and \"interchangeability\" for threaded fasteners in use, it is highly necessary to establish specific standards for electroplated coatings. The GB/T5267.1-2002 standard is one of the standards in the **\"Surface Treatment of Fasteners\" series; this standard includes: GB/T5267.1-2002 ； GB/T5267.2-2002, two standards. This standard is equivalently adopted from the international standard ISO4042 ； 1999. This standard replaces the GB/T5267-1985 standard. 06 Basic Knowledge and Maintenance: Producing double-headed bolts requires specific equipment and machine processing. The actual processing procedure is relatively simple, consisting of the following steps: First, it is necessary to straighten the material using a straightening machine; only after this step can the next one be carried out. The next step involves using a cutting machine to cut the straightened, long pieces into the lengths required by the customer, thus completing the second step. The third step is to pass the cut pieces through a thread rolling machine to create threads on them. At this point, a standard double-headed bolt has been manufactured. Of course, if other requirements exist, additional processing steps will be needed. Generally, a bolt refers to a screw with a relatively larger diameter; according to this definition, a screw has a much smaller diameter compared to a bolt. Double-headed bolts lack heads; they are also sometimes referred to as double-headed studs. Both ends of a double-ended bolt are threaded; there are no threads in the middle, which is a smooth shank. Double-headed bolts are used in large equipment such as reducer frames. In practical applications, external loads cause vibrations; combined with the effects of temperature, this results in a decrease in friction. Over time, this causes the threaded connections to loosen and eventually fail. Therefore, it is necessary to carry out proper maintenance of the double-headed bolts on a regular basis. Double-ended bolts or anchor bolts may develop problems under prolonged mechanical friction. When such issues arise, the engine oil pan must be removed so that the condition of the engine bearings can be carefully inspected. It’s also necessary to check whether the clearance between the bearings is excessive; if it is, they must be replaced promptly. When replacing the studs, the rod bolts also need to be replaced. For some large pieces of equipment, such as nail-making machines, if it is noticed during normal operation that the engine is running unstably or making abnormal noises, the machine should be shut down immediately for inspection to prevent more serious problems from occurring. During each maintenance session, the newly replaced double-headed bolts and other components that have been replaced must be inspected. The inspection should focus on the heads and guiding parts of the double-headed bolts; it is also necessary to carefully check each part of the threads for any cracks or dents, as well as to verify whether there are any changes in the shape of the bolt teeth. Check whether there are any abnormalities in the pitch; if any abnormalities are found, it must no longer be used. A torque wrench should be used when installing the rod cover. It must be tightened in accordance with the specified standards; the torque should neither be too high nor too low. Additionally, care should be taken to select double-headed bolts and studs from a manufacturer that provides compatible products.