1. When processing a large number of workpieces with high concentricity, piece-by-piece correction will increase a lot of auxiliary time and affect productivity. The previous solution was to add a set of rings, machine a cast iron ring to fit the workpiece inside the ring, and use a chuck to tighten the ring. 2. Due to the wear and tear of the three-jaw chuck during application, three types of accumulated errors have occurred. In order to control the cost, it is usually used improvised, and the cast iron ferrule is modified and a Ф85 elastic ring is added. When manufacturing the elastic ring, the shape and position tolerance must meet the drawing design standards. An opening parallel to the axis direction is cut on the elastic ring, with a width of about 5mm. The material is spring steel, the hardness after quenching and tempering is HRC35~45, because the elasticity is better in this hardness range. When installing the elastic ring, it must be placed correctly to avoid tilting. The centering accuracy of the ground three-claw chuck can be good, and the three-claw chuck should be cleaned before grinding. Read More »

　　1. The manufacturing errors of the positioning parts, guide parts and tool parts on the three-jaw chuck and the amount of wear during use will change the correct positional relationship between the machine tool, the tool and the workpiece, and can cause processing deviations. 2. The size of these machining deviations can also be determined based on the calculation of manufacturing tolerances of key components of the fixture. It is also possible to measure the actual deflection of a current set of fixtures or a set of fixtures that have been used and worn. According to the measurement results, the centering error of the three-claw self-centering chuck usually can reach 0.1~0.15mm. 3. From the structure of the three-claw self-centering chuck, basically every part of it is a clearance fit. There are certain gaps between each part. For example, the I-shaped groove of the claw and the three-claw chuck housing slide back and forth, creating a certain gap; the plane thread is sleeved on the mandrel of the housing and needs to be rotated, so there is a gap; the three-claw chuck is locked on the flange and also has radial movement. Read More »

　When used for a long time, the three-jaw manual chuck will suffer from reduced coaxiality and bell mouth phenomenon, which directly affects the machining accuracy and clamping reliability. Practice has proved that using the following method to correct it is simple and practical, and the effect is obvious. You might as well give it a try. Taking the positive jaw chuck as an example, first use an external clamp to clamp a round bar of appropriate diameter, start the machine tool, and turn the outer circular part of the jaw. Then use an inner support to clamp a ring piece, start the machine tool, and turn the inner circular part and end face of the claw. Obviously, this can significantly improve the coaxiality between the machined inner circle of the claw and the machine tool spindle, eliminate the bell mouth phenomenon, obtain higher accuracy, and achieve the purpose of correction. Specific application fashion should pay attention to the following points. The outer circle of the round rod and the inner circle of the ring must be processed in advance and have a certain degree of accuracy. And the inner diameter of the ring body should not be too small, otherwise the concave arc of the claw surface will be too deep, and the surface of the workpiece will be easily damaged when clamping large-diameter workpieces, so attention must be paid. Running around looking for the chuck, times Read More »

　　First, there is a certain taper between the chuck and the spindle. The connection uses 6 hexagonal socket head bolts in the center. To install and replace the chuck, you need to use an hexagon socket wrench to remove the 6 screws. The second type. The connection between the chuck and the spindle relies on the half-cylinder behind the chuck and the half-cylinder in the spindle to engage and fasten each other. Installation and replacement are to use the chuck key to turn the semi-cylinder in the spindle, and the column in the chuck is in a 90-degree engagement and fastening position. It is relatively simple to install and replace. The third type. It is also the most common connection form between the chuck and the spindle. To install or replace, loosen the nut, then rotate the disc at the spindle position a little distance, and the three claws with the connecting screw can be removed or installed. The fourth type. There is a threaded direct connection between the chuck and the spindle. This form of connection is relatively stable. Installation and replacement. Just like removing a nut, turn it clockwise to install it. Counterclockwise is to remove. Read More »

　Through the factory tour arranged by the tour group, we have a close understanding of the development process, product technology, business philosophy and corporate culture of world-class companies. What makes us sigh is that these high-precision machine tools do not have many new designs in structure. Instead, they optimize the classic structure to the extreme. For example, Okuma uses dynamic pressure. The application of new technologies is mostly reflected in functional components, such as Okamoto's vacuum suction cup. Unclamped workpieces can be suspended on the suction cup and slide freely, and the workpiece can be sucked at any position when needed. We also saw workers processing parts on ordinary lathes at one booth, which shows that even now, ordinary machine tools have not completely disappeared. Through the visit, it was like watching a documentary. From the beginning to the present, the process of these companies is similar to that of many companies in my country. The difference is that they focus more on their own fields, on making the highest level products, and on serving users. Time is short, it is inevitable Read More »

The three-jaw chuck is also called the three-jaw self-centering chuck. It determines the rotation center of the workpiece based on the circumference of the workpiece clamping part, but its centering accuracy is not very high. Generally, depending on the usage occasion, a three-jaw chuck with higher clamping accuracy is selected for finishing turning, grinding, and milling parts with higher precision using a universal indexing head, while in rough turning and grinding, milling and other processes where invisible position accuracy is required, a three-jaw chuck with lower clamping accuracy is used. The principle of clamping workpieces with a three-jaw chuck is to use the chuck wrench to rotate any one of the three bevel teeth on the circumference. This drives the plane thread to rotate and drives the three claws to move together, which plays a role in self-centering the workpiece. From a mechanical structure point of view, the three bevel teeth of the chuck have the same function, but after careful inspection, the accuracy of the three bevel teeth in clamping the workpiece is not the same, and the difference is also large. Read More »

　　The three-jaw chuck consists of a chuck body, movable jaws and a jaw driving mechanism. Under the guide part of the three claws on the three-jaw chuck, there are threads that mesh with the flat threads on the back of the dish-shaped bevel gear. When the small bevel gear is turned with a wrench through the square hole, the dish-shaped gear rotates, and the flat threads on the back simultaneously drive the three claws toward or away from the center to clamp workpieces of different diameters. It is used to replace the three claws with three anti-claws to install workpieces with larger diameters. The self-centering accuracy of the three-jaw chuck is 0.05-0.15mm. The accuracy of processing workpieces with a three-jaw chuck is affected by the manufacturing accuracy of the chuck and the wear and tear after use. Chucks are divided into manual chucks and power chucks according to the power used to drive the jaws. Manual chuck: It is a universal accessory. The commonly used three-jaw chucks are self-centering three-jaw chucks and four-jaw chucks in which each jaw can move independently. The three-jaw chuck has a small bevel gear driving a large bevel gear. large bevel gear Read More »

　1 inch is equal to 25.4MM, but 5 inches is 127mm, which is 130 diameter relative to the chuck. Inch (inch) is a unit of length used in the United Kingdom (UK, the British Commonwealth) and its former colonies, generally 1in=2.54cm. In the imperial system, 12 inches is 1 foot, and 36 inches is 1 yard. Main dimensions of 80 chuck claws: 12mm thick, 7mm wide side grooves 100 main dimensions of chuck claws: 15mm thick, 8mm wide side grooves 130 chuck claw dimensions: 16mm thick, 8mm wide side grooves 160 chuck jaw main dimensions: 18.5mm thick, side groove width 10mm 200 chuck jaw main dimensions: 22mm thick, side groove width 10mm 250 chuck jaw main dimensions: 27mm thick, side groove width 10mm 320 chuck jaw main dimensions: 36mm thick, side groove Read More »

　　What are three-jaw chucks: Three-jaw chucks are divided into hydraulic chucks, manual chucks, pneumatic chucks, vertical chucks, built-in integrated chucks (cylinder and chuck integrated), electric chucks, mechanical chucks, etc. Among them, the three-jaw hydraulic chuck needs to be used with oil cylinders of the same size. It is easy to install, fast and safe to clamp, and is suitable for processing large quantities of regular parts. Manual chucks are divided into ordinary manual chucks and powerful manual chucks. Ordinary manual chucks are equipped with hard claws and are divided into front and reverse claws. They are suitable for rough processing of irregular-shaped and regular parts. The powerful manual chuck is equipped with hard claws, and optional soft claws are available. The hard claws are used the same as ordinary manual chucks, while the soft claws can directly process parts into finished products. More versatile. Pneumatic chucks are high-precision chucks that generally process large quantities of workpieces with low hardness, stable clamping force and high precision. Vertical chucks require special equipment. Generally processing irregular work with larger specifications Read More »

Inspecting the hollow double-piston cylinder is mainly to detect its degree of wear, that is, the roundness and cylindricity of the cylinder. 1. Measurement of the cylinder bore of the cylinder block ① The measurement part of the hollow double-piston cylinder bore is based on the wear pattern of the cylinder. When measuring the cylinder diameter, measurements should be made in the three axial sections and directions of the cylinder. The upper section is in the upper part of the cylinder, which is equivalent to the position of the piston ring when the top dead center of the piston stroke is about 15mm; it is far away from the top of the cylinder; the second section is in the middle of the cylinder, about 35mm from the top of the cylinder; the third section is in the lower part of the cylinder, close to the lower edge, and about 70mm from the top of the cylinder. ② Adjust the measuring cylinder gauge, measure the length of the connecting rod, select the appropriate measuring connecting rod and fixing nut according to the diameter of the cylinder to be measured, and screw into the lower end of the measuring rod. Adjust the length of the connecting rod so that the total length of the connecting rod and the movable measuring rod adapts to the diameter of the cylinder being measured, even though the measurement range can include the larger and smaller wear diameters of the cylinder. ③ Measure the diameter of the hollow double-piston cylinder with small wear Read More »

A collet is a locking device that clamps workpieces and is commonly used on drilling and milling machines and machining centers. The following is the installation method of the collet chuck shared by the editor. First, the installation steps of the collet chuck 1. Check whether the thread of the connecting nut can be locked into the connecting pipe. 2. Tighten the coupling nut onto the sleeve. 3. Reduce the oil pressure to the lowest level and drive the hydraulic cylinder to stop the piston at the front end. Rotate the chuck to lock the connecting nut into the threads of the connecting pipe. When locking, the taper hole of the chuck must be concentric with the taper of the spindle, and the alignment hole of the chuck must be aligned with the alignment button on the nose of the spindle. 4. Operate the hydraulic cylinder to move the piston backward, combine the taper of the chuck with the spindle, and confirm that the centering button is installed in the chuck. 5. Fix the chuck and the spindle with the locking screw, gradually increase the oil pressure, and repeatedly drive the chuck to the maximum allowable thrust. Then there are the steps to install the collet chuck: 1. Remove the limit cover, 2. Read More »

The pressure plate clamp is a type of fixture that uses a pressure plate to press the upper and lower workpieces together to create indentations on the workpieces. The pressure plate clamp can exert a clamping force on the workpiece, so that the clamped workpiece obtains a certain tightening force, so that the processed surface and the pressure plate closely match, so that the workpiece surface and the positioning element fit accurately and closely, so as to achieve the purpose of correctly positioning the workpiece. Pressure plate clamp is a device used to clamp workpieces. According to the clamping force required by the workpiece, it can be divided into three categories. One type is the commonly used ordinary pressure plate, which is used to clamp general workpieces. The pressure plate clamp is a type of fixture that uses a pressure plate to press the upper and lower workpieces together to create indentations on the workpieces. The pressure plate clamp can apply clamping force to the workpiece, so that the clamped workpiece obtains a certain tightening force, so that the processed surface closely matches the pressure plate. Features of pressure plate clamps: 1) reliable clamping, stable clamping force, the size and direction of the clamping force can be adjusted; 2) the clamping components will not be damaged due to excessive pressure Read More »