For the use of mechanical equipment, if you want to operate normally, you must have fasteners. However, many friends will find that almost all fastening designs on many design drawings use hexagon socket screws, whether countersunk or not.
So why do so many devices use socket head screws instead of socket head screws? What's good about it? Today, Xiao Rui will discuss with you the advantages and disadvantages of external hexagon screws and internal hexagon screws.
The thread on the external hexagon screw is generally fine thread, and the external hexagon screw with common thread with ring thread has good self pinning property. It is mainly used on thin-walled parts or under impact, vibration or alternating load.
Generally, external hexagon screws are made with partial threads. Full thread external hexagon screws are mainly used for external hexagon diameter with short nominal length and occasions requiring longer threads. The external hexagon screw with hole is used for occasions requiring external hexagon screw locking. External hexagon screws with reamed holes can accurately fix the phase position of the connected parts. And can be subjected to shearing and extrusion caused by the die force.
The advantages of the outer hexagon are that the pre tightening contact area is large, and a large pre tightening force can be used. It is generally used in large equipment, and the price is lower than that of the inner hexagon. The disadvantages are that it occupies a large space and cannot be used in the counterbore.
Hexagon socket screws are commonly used in machinery, which are mainly easy to fasten, disassemble and not easy to slide. Allen wrenches generally have a 90 ° turn. One end is long and the other is short. When using the short side to screw, holding the long side can save a lot of force and better tighten the screws. The long end is divided into a round head (hexagonal cylinder is similar to a sphere) and a flat head. The round head can be easily inserted and disassembled obliquely, and some parts that are inconvenient to lower the wrench can be installed.
The manufacturing cost of the outer hexagon is much lower than that of the inner hexagon. Its advantage is that the screw head (the stress position of the wrench) is thinner than the inner hexagon. In some places, the inner hexagon can not be replaced. In addition, machines with low cost, low power strength and low precision require less hexagon screws than hexagon screws.
The advantage of hexagon socket is that it takes up little space and can be used as a countersunk head. It is generally used on small equipment. The disadvantage is that the preload contact area is small and too much preload cannot be used. The price is a little expensive. There is no full thread beyond a certain length.
Then why can hexagon socket screws be seen in many mechanical equipment?
1、 Bear more load
There are six bearing surfaces of the hexagon socket bolts, which are more bearable than the slotted screws and cross shaped screws with only two surfaces.
Note: the material of hexagon socket bolts is generally made of stainless steel, carbon steel and alloy steel. There is basically no difference between them and other types of screws. The higher the performance grade, the greater the strength. When selecting screws, it is necessary to select screws with appropriate performance grade in strict accordance with the use requirements. Different grades have different prices.
2、 Can be buried
The whole nut is sunk into the workpiece, which can maintain the flatness and aesthetics of the workpiece surface.
3、 Easy installation
Compared with the outer hexagon screw, the inner hexagon is suitable for more assembly occasions, especially for narrow occasions. Therefore, it is very convenient for assembly and maintenance and debugging.
4、 Not easy to disassemble
We usually use open-end wrenches, screwdrivers, solid wrenches, etc., and special wrenches must be used to disassemble hexagon socket bolts. Therefore, it is not easy for ordinary people to disassemble, which is also a benefit.
Display of some products of Jinrui
Jiangsu Jinrui metal products Co., Ltd. is the production base of Shanghai Jinrui standard parts. The factory covers an area of more than 20000 square meters, has a registered capital of 50 million yuan, a total investment of more than 100 million yuan, an annual output of more than 20000 tons, and its products are exported to more than 40 countries overseas.
Since its establishment in 2001, Jinrui has developed into a brand-new layout with Jiangsu Hai'an as its production base and Shanghai Baoshan and Henan Nanyang as its sales centers after more than 20 years of unremitting efforts.
At present, Jinrui's main products include the following six categories:
1. The main products of bolts include: metric and American round head oval neck bolts (also known as fishtail bolts), inner and outer hexagon bolts, hexagon flange bolts, carriage bolts, hub bolts, etc
2. Stud products: full thread thread, double headed studs, etc
3. Nut products: Hexagon nuts, flange nuts, heavy nuts, square nuts, butterfly nuts, etc
4. Screw products: self tapping screws, self tapping and self drilling screws, wood screws, various machine screws, etc
5. Washer products: flat washer, spring washer, square washer, locking washer, etc
6. Fastener related non-standard products
Jinrui's wire drawing plant also provides processing services such as fine drawing, rough drawing and spheroidization of wire rod, and supplies finished wire rod of various domestic large brand steel plants.
Based on the business philosophy of "pioneering innovation and pursuing excellence", Jinrui has successively introduced multiple models of starting and forming machines, threading machines, nut machines, hot heading and rolling machines, lathes, large-scale hot heading machines and their supporting testing equipment, such as magnetic particle flaw detection machines, metallographic analyzers, salt spray testing machines, direct reading spectrometers and optical screening machines, tensile machines, Vickers hardness meters, Rockwell hardness meters, etc., and has independent R & D departments, It can produce various high-quality fasteners such as GB, DIN, ANSI, JIS and ISO international standards. The products are widely used in petroleum, chemical industry, boiler, wind power generation, expressway guardrail, elevator guide rail, machinery manufacturing, construction sites, auto parts and medical devices.
Jinrui has flourished since its establishment. It integrates the advantages of each family, careful design and strict selection of materials to make the products more durable and won the praise and praise of the majority of users. Jinrui won the ISO9001:2000 international quality system certification in 2001, the special equipment manufacturing license in 2010, and the TS16949 automobile quality management system certification in 2012. Moreover, the products are covered by the people's Insurance Company of China "global product liability insurance", to ensure that every screw can be used with confidence, firmness and peace of mind!
No matter now or in the future, Jinrui will always grasp the core service concept of "quality first, science and technology to prosper the enterprise, user first, and considerate service", and sincerely provide you with high-quality services and high-quality products. Jinrui will also become your most loyal and long-term partner.
