Umbrella rotary top, also known as the top of the big head or the top of the pipe, is mainly used to support the sleeve parts, can withstand higher cutting load, improve the workpiece support stiffness and reduce the workpiece deformation. The “National Standard for Positioning, Clamping, and Device Integrated Labeling - JB/Z174-82†has an annotation of the “Umbrella-shaped top bedside tail umbrella-shaped top positioning and lever clamping†in the circular outline of the tube blank. Bedding plum blossoms are also often used in the processing, and the positioning and clamping of the top of the bedside umbrella shape is often used. The cone angles of these umbrella-shaped tips or plum blossom tip heads are generally 60° or 75°, and a few are 90°. The advantages of the large cone angle umbrella-shaped rotary tip are good versatility. One tip can be used to process workpieces with internal hole sizes ranging from tens of millimeters to one hundred and two hundred millimeters. The disadvantage is that the positioning accuracy is low. The position of the end face has a large error. For the shortcomings of the large taper umbrella-shaped turning top, the author designed and manufactured a series of small taper turning tips. Through a few years of production practice test, the effect is very good. Now it is introduced as follows. 1 small taper rotary top structure
1. Taper sleeve 2. Cap 3, 4. Washer 5. Screw cap 6. Taper shank 7, 13. Screw 8. Lever 9, 11, 12. Bearing 10. Oil cup 14. Screw plug
Small Taper Rotary Top Structure
The figure above shows the small taper rotary tip. The solid line in the figure shows the small taper rotary tip structure with the small end of the sleeve smaller than Ø30mm and the double dotted line is the small tapered rotary tip structure with the small end of the sleeve larger than Ø30mm. The taper cone angle is generally 30°. For further improvement of positioning accuracy, it can be reduced to 20° or even 15°. Cone material is 9Mn2V, heat treatment 60 ~ 64HRC, so that it has a higher hardness and wear resistance, prolong life. Tapered shank material is 40Cr, heat treatment 40 ~ 45HRC. When a gap seal is used between the taper shank and the screw cap, the clearance is not more than 0.2 mm (For small taper rotary tips whose d0 is greater than Ø100 mm, a felt seal is preferred). Two: Single-precision single row radial ball bearings ensure that the top has a high positioning accuracy and can withstand radial forces: E-class precision one-way thrust ball bearings are used to withstand axial loads. The tolerance zone of the hole matching the bearing sleeve bore and the bearing is M7: the shaft tolerance zone of the taper shank and the single row radial ball bearing is h6, and the shaft tolerance zone of the thrust ball bearing surface is j6. During assembly, grease is filled in the rotating top bearing and the screw cap hole. After the bearing clearance is adjusted, the screw cap is tightened with a screw. Finally, the morse taper shank is inserted into the taper hole of the universal cylindrical grinding machine, and the cone sleeve is rotated by a dial to finely grind the cone surface to ensure the tolerance of shape and position, size and surface roughness requirements. This method is also used for taper cone wear, bumps or dressing after deformation. 2 Applying our factory in the processing of 300mm long bushings of series tubular pumping products (in which the nominal diameters of the inner bores are of five sizes: 32, 38, 44, 56 and 70mm, wall thickness 5.5～8mm), the small taper rotation tip is used. Grind the outer circumference of the hardened long liner. The method is as follows: two small taper rotary tops are respectively installed in the taper holes of the cylindrical grinding machine spindle and the tailstock sleeve (the lever on the main shaft should be added), using the frictional force between the periphery of the workpiece hole and the taper sleeve. The rod drives the workpiece to rotate, relying on the compression mechanism of the grinder tailstock to force the workpiece and grind the outer circle. The workpiece surface roughness Ra0.4μm, roundness 0.005mm, the coaxiality of the outer circle to the inner hole within 0.01mm (excluding the shape error of the workpiece hole), loading and unloading the workpiece fast and convenient, with the past using the ball spindle, roll Compared with the cylindrical mandrel grinding outer circle, the labor intensity of the workers is greatly reduced, and the work efficiency is improved several times, which is highly praised by the workers.As a leading enterprise in the galvanized & pre-painted industry in china. Shandong Xinghan Materail Corporation with an annual output of 1 million tons of picking coils. 1 million tons of cold roll. 800,000 tons of hot-dipped galvanized and galvalume steel sheets. 450,000 tons of thicker galvanized steeel sheets.300,000 tons of pre-painted steel sheets. occupies a stable leading position in the industry.
Gi Coil,Ppgi Coil,Galvanized Coil,Galvanized Steel Coil
SHANDONG XINGHAN MATERIAL CORPORATION , https://www.xinghansteel.com