Process
Inspection for cutting riser of sand blasting, surface cleaning, inspection for defects, repair of heat treatment, surface cleaning, inspection, correction and warehousing
Drop temperature of casting
For general castings, when the temperature drops to 250-450 ℃, sand can be removed.
Holding time of castings under 10 tons
Desanding
Master the temperature of the casting’s residence time in the mold and packing time.
Prevent the ring or the casting from being shaken or deformed on the sanding machine.
Shot blasting
Adjust the shot blasting time for different castings.
Check whether all parts of the equipment are normal and can be used only after idling operation is normal.
Proper steel shot shall be selected according to the casting, and the shot blasting shall have uniform particle size.
The shot blasting equipment must be kept in good airtight condition. When the impeller of the shot blasting machine is not completely stopped, it is not allowed to open the shot blasting machine chamber, so as to avoid the shot flying out and hurting people.
The wear parts such as the directional sleeve, distribution wheel and guard board of the shot blasting machine shall be replaced in time according to the wear degree.
The casting into the shot blasting chamber shall be large and difficult to match, so that the shot blasting machine can produce the best effect.
Check whether the hook steel rope is reliable.
Cutting of sprue and riser
The root of the casting riser can be cleaned when cutting the casting riser. The cleaning height should be greater than the cutting allowance before cutting.
The cutting riser shall be cut at one time without stoppage.
The riser with a diameter of more than 500mm can be placed in the original place after cutting, and the surrounding area shall be buried with dry sand for slow cooling.
If the riser is separated from the casting after the big riser is cut and cannot be insulated, the casting shall be immediately put into the kiln for heat preservation and slow cooling.
When cutting gear castings in winter, flame can be used to bake the riser for one circle before cutting the hub and riser. Symmetrical cutting shall be used to avoid deformation and cracking of the castings.
When cutting the riser, the cutting torch should swing up and down a little (i.e. not cutting forward in a straight line), otherwise the oxide skin and slag are easy to block, making the cutting impossible.
When the riser diameter is more than 300 mm, due to the cutting thickness limitation of the cutting torch, two feed methods can be used.
The upper tie bar of casting shall be cut off after heat treatment.
Generally, the riser of castings is cut at normal temperature before heat treatment, and the easily cracked parts can be cut after heat treatment or preheating.
Surface cleaning
Remove the outer flash burr, drape seam, tie bar, riser and other redundant parts.
The cut root of the pouring riser shall be polished to the specified requirements without exceeding the standard.
The traceability mark cannot be removed, it shall be polished clearly, and the unclear place shall be corrected and restored.
Ensure that the shape of the cleaned casting meets the requirements of the drawing and the weight is within a certain range.
Check and polish the cutting tools immediately, and replace the grinding wheel and cutting blade to improve the efficiency and safety first.