What is the specification for the grinding and polishing process of a mold surface?

1. What is the preparation before polishing

1. The polishing worker must be trained and pass the examination to get ithe nduction certificate before they can start.
2. Define the workpiece process requirements, material , processing part, shape, size and polishing precision requirements
3. Before polishing, it is necessary to check whether the polished surface has sags,overcuts, deformations and blisters, and whether the remaining polishing margin is sufficient.
4. According to the process specifications to select applicable tools, fixtures, main and auxiliary materials.
5. Properly protect the workpiece according to the process requirements.

2. Clamping and protection of workpiece 

1. For below 20Kg --higher or longer workpieces, it requires vise clamping on the polishing table.
2. For larger and heavier workpieces must be used on the polishing table before and after the magnet, screw clamping code for fastening.

3. When using work car to polish the workpiece, it must be used wedges or related measures to ensure work safety.
4. For small and easy to bump or scratch workpieces, rubber plates must be used to protect the surface.
5. Workpieces with sharp corners and corners must be protected with tape to avoid to damage the personnel and workpieces.
6. For workpieces that need to maintain edges and sealing positions, stoppers (saw blades or iron sheets) or stoppers can be used to prevent edge chamfering and rounding on the side that is not being polished.

3. Self-inspection content and scope

1. Whether the sealing surface is rounded or collapsed;
2. Whether to destroy the original draft angle;
3. Check the size of each polishing surface to see if it exceeds the reserved amount;
4. Whether the fillet at the bottom of the cavity is recessed into the side and bottom surface;
5. Whether there is an inversion phenomenon;
6. Whether its roughness has reached the drawing requirements;
7. After passing the self-inspection, send it to the team leader (or inspector) for inspection.

4 What is the matters needing attention in polishing operation

1. Before grinding, check whether the grinding allowance is sufficient, and the grinding and polishing amount cannot exceed the reserved amount
The surface polishing amount after grinding can not exceed the reserved amount by 0.05~0.06mm;
Unground surface, electro-erosion or wire-cut surface grinding and polishing can not exceed the reserved amount by 0.08~0.1mm;
The amount of single side and deep grinding of ribs cannot exceed the reserved amount by 0.03~0.08mm.

2. When operating with the polishing machine,Staff must concentrate on preventing grooves, exceeding the margin, not allow long time processing in the same part
3. After each polishing, it must be cleaned with a whiskey cloth and then proceed to the next polishing step.
4. After each polishing, it must be cleaned with cotton or soft paper, and then the next step of polishing.
5. Before polishing the mold, first determine the processing procedure:
According to different surface conditions and roughness, to select the appropriate process and suitable tools (such as diamond file, sandpaper, mold oil stones) for the start and required sequence.
According to the geometry, roughness and process requirements of the mold cavity,determine the range of power tools and grinding tool heads to achieve targeted processing.
6. Pay attention to the grinding and polishing of the sealing surface, especially the part of the special identification symbol of the product and the sealing surface should not cause rounded corners and collapsed corners;
7. The polishing area requires a clean environment. Pay attention to the protection of the polished surface during the polishing process;
8. If some parts need to be polished together after assembly, they are not allowed to be polished separately;
9. After polishing, the polished surface should be sprayed with anti-rust oil after self-inspection and inspection, and protection work should be done to prevent bumps and scratches;
10. All kinds of oilstone, sandpaper, diamond grinding paste and diamond files must be placed in a special tool box with corresponding labels according to their model and specifications.

5:Ultrasonic polishing machine

1.The clamping sintered diamond file mainly processes and removes the electric processing layer of the bottom plane and the side plane of the cavity;

2.Install electroplated diamond files to remove the electro-processed layer and rough cutting marks in narrow planes, cavity side walls, dead corners and sharp corners;
3.Clamp various oilstones to trim the shape and position tolerances caused by rough machining and improve the roughness;
4.Clamping copper, soft and hard wood and adding various grit sizes of abrasive pastes to achieve fine polishing of the processed surface

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