Wrench is a commonly used installation and disassembly tool. It is a manual tool that uses the lever principle to turn bolts, screws, nuts and other threaded fasteners that hold the openings or sockets of bolts or nuts. Wrenches are usually made of structural steel made of carbon or alloy materials. The wrench is usually provided with openings or sleeve holes for clamping bolts or nuts at one or both ends of the handle. When used, external force is applied to the handle along the direction of thread rotation, and the bolts or nuts can be screwed. texture of material: 1. Chrome vanadium steel: chemical symbol CR-V, which is of better quality among steels; 2. Carbon steel: the quality is general, and there are many in circulation in the market. Classification: There are basically two types of wrenches, dead wrenches and live wrenches. The former refers to a spanner with a fixed number, and the latter is an adjustable spanner. 1. Solid wrench: one end or both ends are provided with openings of fixed size to screw nuts or bolts of certain size. 2. Ring spanner: both ends have working ends with hexagonal holes or twelve corner holes, which is suitable for occasions where the working space is narrow and ordinary spanners cannot be used. 3. Dual purpose wrench: one end is the same as the single solid wrench, the other end is the same as the ring wrench, and both ends are screwed with bolts or nuts of the same specification. 4. Adjustable wrench: the opening width can be adjusted within a certain size range, and it can turn bolts or nuts of different specifications. The structure of the wrench is characterized in that the fixed jaw is made into a flat jaw recess with fine teeth; One end of the movable jaw is made into a flat jaw; The other end is made into a concave jaw with fine teeth; Press the worm downward, the movable jaw can be quickly removed and the jaw position can be changed. 5. Hook wrench: also known as crescent wrench, it is used to turn flat nuts with limited thickness. 6. Socket Wrench: it is composed of a plurality of sockets with hexagonal or twelve corner holes and equipped with handles, extension rods and other accessories. It is especially suitable for turning bolts or nuts with very narrow positions or deep recesses. 7. Hexagon socket wrench: L-shaped hexagon rod wrench, specially used for turning hexagon socket screws. The model of hexagon socket wrench is based on the dimension of hexagonal opposite side, and the dimension of bolt has national standard. Purpose: it is specially used for fastening or disassembling round nuts on machine tools, vehicles and mechanical equipment. 8. Torque wrench: it can show the applied torque when turning the bolt or nut; Or when the applied torque reaches a predetermined value, a light or sound signal is emitted. The torque wrench is applicable to the assembly with clear provisions on the torque. Hand wrench: Manual wrench is also called ordinary wrench, which is mainly used in ordinary life and work. It is relatively simple to use. It is mainly divided into single end solid wrench, double end solid wrench, adjustable wrench, Box Wrench, multi-purpose wrench, percussion wrench, socket wrench, socket driver, torque wrench, torque wrench, cross wrench, ratchet wrench, hook wrench, hexagon wrench, square wrench, manual clutch torque wrench, pipe wrench T-type wrench, L-type wrench, Trident wrench, crescent wrench, oil barrel wrench, tire wrench, spark plug wrench, filter wrench, combination wrench and other wrenches. Torque wrench is divided into sound wrench, pointer wrench and digital display wrench. Use of hand wrench Wrench 1. Select corresponding wrenches according to the characteristics of the fasteners to be fastened. 2. Tighten, hold the end of the wrench handle with your hand, and tighten it forcefully clockwise; Loosen and rotate counterclockwise. Manual wrench features Simple operation, low price and high labor intensity Application and technical characteristics of open-end wrench Screws are the main fasteners in mechanical equipment. Open end wrenches are important tools for processing, production and maintenance in the mechanical industry. This project is a revolution of traditional wrench tools. It has the following advantages. 1. It can work quickly. The working speed is three to four times faster than that of the traditional wrench and faster than that of the fast wrench. 2. An open-ended wrench can be used for 2-6 kinds of screws, while a double ended solid wrench can only be used for 2 kinds of screws. One open-ended wrench is equivalent to 2-3 solid wrenches, and it is equivalent to an adjustable wrench, but it can work quickly without adjusting the opening. 3. It has long service life and can not be damaged, and the front quick wrench is easy to be damaged. 4. The manufacturing process is simple and its cost is lower than that of solid wrench. 5. Light weight, easy to carry and labor-saving. Surface treatment: 1. Bright chrome: bright as a mirror; 2. Chromite: matte; 3. Electrophoresis: it is black and bright. Under the action of external DC current, the charged particles will move directionally to the cathode or anode under the dispersed dielectric force to promote the separation of substances; 4. Phosphating: black, but with dark luster. Immerse the substance in the phosphating solution and deposit a layer of crystalline phosphorus insoluble in water on the stool surface, which is the process of hydrochloric acid conversion. 5. Gray nickel: it is a brand-new surface treatment method with strong anti rust ability and will increase the service life of the product. 6. Other treatments include blackening, nickel iron alloy, pearl nickel, black nickel and titanium plating