First, choose a high-quality diamond wire drawing dies
At present, many domestic manufacturers are still using backward equipment, use manual operation to grind pass, therefore, there is the following problem: pass parameter fluctuations, work hard to process the flat cone; sizing zone and work zone transfer easy to grind out the transition at the corner, the wire sizing zone in secondary compression, increased external friction, shorten the length of the sizing zone, shortening the life of mold; worn grinding repair frequency varies, the use of non-standard, resulting in poor consistency pass. Detection means also behind, we can only rely on visual or magnifying glass, microscope and other simple tools to detect, but also pay attention to the mold surface finish of the hole size can not effectively detect, let alone control.
The foreign cable mold grinding process commonly used high-speed mechanical grinding machine, as well as diamond plated metal grinding, smooth operation of the equipment, grinding and the use of standardized specifications make the product more accurate. Pass the size of the mold using contour logger and aperture measuring instrument to detect and check the cable model with a special microscope to check for surface finish.
Second, the installation drawing equipment shall be reasonable
1.Need a drawing machine installed base is very stable and avoid vibration phenomena.
2.Pull the process to avoid frequent start stop, start drawing the tensile stress due to friction caused when normal ratio of friction when the drawing is much greater, which is bound to increase the mold wear.
3. To make the installation through commissioning wire drawing hole centerline axis of symmetry of the mold, the wire and cable model stress evenly.
Third, choose a good pass diamond wire drawing dies
1. The mold each part must be clear, so that each part can give full play their respective roles, to avoid a reduction in the angle of the actual length of the transition zone sizing;
2. longitudinal section of line pass each part must be straight, flat work force smallest cone drawing;
3. sizing zone must be straight and reasonable length. Sizing zone too long, cable friction increases, after the wire pulled out easily cause necking die hole or break, sizing area is too short, it is difficult to obtain a stable shape, size, accuracy and good surface quality of the wire, while the die hole also will soon wear tolerance.
4. The extension of the entrance area and workspace height, the wire into the middle section of the die hole taper work, the use of the wedge on the inlet cone angle and work half cone angle formed by the establishment of "wedge effect", in a more dense solid wire surface lubricating film, reducing wear, suitable for high-speed drawing;
Through practical application, using linear theory to design a pull mode, its life than the R-type cable model increased by 3-5 times.
Fourth, the choice of lubricants must be accurate
In the drawing process, the supply of lubricants and lubricant quality are affecting the adequacy of pull mode of life. Thus requiring the lubricant oil base stability, good oxidation resistance, with excellent lubrication, cooling and cleaning of the entire production process has always been to maintain optimum lubrication, in order to form a layer able to withstand high pressures without being destroyed The film, the work area to reduce friction and improve mold life.
Use of the process, we must continue to observe the condition of lubricating oil, lubricating oil, if found serious discoloration or metal powder to increase, we must promptly replace or filtered, to avoid lubricating oil lubricating performance degradation due to oxidation, while avoiding drawing process tiny shed metal particles mold damage.
V. wire to pretreated
1. Surface preparation: For surface dirt, adhering more impurities wire, first after washing, drying and then be drawn; for more wire surface oxide scale, first through a fine acid, drying then be drawn; for the present on the surface from the skin, dimples, heavy leather and other phenomena of the wire, but also through the grinder after grinding were conducted drawing;
2. Heat treatment: For the hardness is too large or uneven hardness of the wire, first reduce the hardness by annealing or tempering, and the wire holding good hardness uniformity then drawn.
Sixth, to maintain proper drawing surface shrinkage
Diamond Drawing mold itself has a hard, brittle characteristics, if for Omo shrinkage of necking drawing, can easily lead to mold can withstand the stress fracture scrapped, and therefore depending on the mechanical properties of the wire, select the appropriate surface Drawing shrinkage rate. Stainless steel wire drawing diamond die, usually single-channel surface shrinkage rate does not exceed 20%.
Seven, regular maintenance of diamond wire drawing dies
Cable model in the long-term use, the die wall friction by strong metal wire and scouring action will inevitably produce wear and tear, the most common is the emergence of an annular groove Caojing (dents) in the wire at the entrance to the work area. Pull mode ring groove appears exacerbated wear die hole, because the ring ditch because loose and flaking of the core material of small particles into the wire die hole workspace and sizing zone, acts as an abrasive, and enter Wire die hole is like grinding as increased wear die hole. If we do not fix exchange, then the ring groove will continue to accelerate the expansion, so the repair more difficult, there may even be a crack in the annular groove deeper, broken the mold completely collapse scrapped. |
