Ten Major Processes of Shoemaking

1. Warehouse management of raw and auxiliary materials

 

Daily entry and exit of raw and auxiliary materials into and out of the warehouse must be recorded in material and inventory accounts, and managed using microcomputers;

Incoming and outgoing materials must be managed by dedicated personnel to avoid errors; 3. When feeding, quality inspectors must be present to inspect whether the quality is correct and whether the color is correct.

 

2. Cutting workshop management

---Material requisition must be handled by a dedicated person, who will be uniformly assigned to employees by the team leader;

---When cutting genuine leather, it is better to use hydraulic swing arm cutting machine or hydraulic flat cutting machine because it can only be cut in a single layer;

---When cutting nylon fabric, Teflon fabric, canvas, and thinner PVC leather, due to the soft material and the ability to cut multiple layers at once, hydraulic flat cutting machine or hydraulic gantry cutting machine should be used.

---When cutting the middle bottom plate, due to the hard material and the ability to cut multiple layers at once, hydraulic flat cutting machine or hydraulic gantry cutting machine should be used.

---Any cut parts, especially colored leather and fabrics, should undergo quality inspection, color matching, pairing, and quantity counting at the same time to avoid duplicate work when arriving at the sewing department;

---The cutting supervisor should guide employees in the daily maintenance of machines and cutting dies;

---Management personnel must inspect employees at all times to ensure that they follow the knife number on the instruction sheet when using the chopping tool, and teach employees how to self-inspect.

---Teach employees to understand materials that are suitable for use, and pay attention to the arrangement of cutting blades to reduce unnecessary material waste.

 

3. Allocation Center Management

---The allocation center arranges the cut parts neatly according to the order situation and waits for processing;

---The pre-cut parts, such as printing, peeling, lining, hot stamping, etc., are all handled by the blending center;

---The processed materials are delivered to the central warehouse material preparation team, which then issues them to the sewing workshop for processing.

---The cut parts such as the midsole, insoles, etc., if no special sewing processing is required, can be sent to the semi-finished product warehouse after completing the necessary processing.

---In the mixing center, after all parts are completed, it is necessary to properly organize the quality and statistical data of all parts of the shoe upper, and prepare to hand them over to the sewing workshop;

4. Needle sewing workshop management

---The process flow and staff configuration for sewing and making uppers in the sewing workshop vary depending on the design of the shoe upper. Generally, if a sewing assembly line can produce 1500 pairs every 8 hours, it requires about 70-80 sewing machines and 10-15 manual workers, totaling 80-95 people;

---When sewing, attention must be paid to the edge distance of the stitching, whether the needle spacing is well controlled, and whether it meets the required standards;

---When sewing, attention must be paid to the correctness of each marking point on the shoe upper components. If the correct marking is not followed during sewing, the shoe upper will be uneven after completion, causing difficulty in clamping and affecting the quality of the finished shoe.

---The sewing workshop must be equipped with small scissors and other tools, and the shoe factory needs to purchase them themselves. ----The prepared shoe uppers must be inspected by the quality control department, and then sorted appropriately according to the shoe size required for each order before being sent to the semi-finished product warehouse, which will then be sent to the clip forming workshop.

---Teach operators to regularly maintain the machine to avoid high failure rates that may affect quality and production

5. Sole workshop management

---Forming bottom production: Attention should be paid to precision to ensure the aesthetic appearance of the finished product; The cost of the mold is high, and the design of the pattern should be in line with the trend to prolong its elimination time and reduce costs; Injection materials (PVC, TPR, PU or EVA) should pay attention to their physical properties and conduct more tests to ensure the quality of the finished product.

---Rubber combination outsole production: pay attention to the quality of natural rubber and strive for stability; The combination ratio of various additives and chemical raw materials will affect the physical properties of the sole, and its ratio and characteristics vary with climate and processing time, which should be recorded as a reference at any time; The changes in sole pattern design must be in line with market trends; Rubber outsole should be stored in a dark place, avoiding direct sunlight, and packaged in black and white PVC bags, otherwise it will age and affect the quality of the finished product. In addition, rubber soles that have been stored for a long time should be used first; The rubber outsole should be surface treated or roughened before bonding to facilitate adhesion;

6. Management of semi-finished product warehouse

---The semi-finished product warehouse is a transfer station for the facial and bottom process flow in the footwear production process.

--- The management of the semi-finished product warehouse should timely urge the sewing workshop according to the production sequence table, and control the issuance of materials in the upper clamping molding workshop;

---Before distributing materials to the upper and sole molding workshop, the semi-finished product warehouse management personnel must pay special attention to quality management and quantity statistics according to the process flow table.

---Each order must be prepared with various materials such as upper, midsole, outsole, insole, inner box, outer box, paper label, etc. before materials can be distributed to the upper molding workshop.

---The daily production rotation should be determined based on the number of last heads ordered, and the molding workshop should receive production according to the table.

---Schedule the entire factory schedule.

---Fill in the production dynamic table every day (including the number of people and materials, the quantity of materials received, the inventory quantity, and the production dynamics of each production line)

7. Management of Clamping and Forming Workshop

---The upper clamping process includes three parts: front upper, middle upper, and back upper.

---The wearing method and length of the shoe arch should meet the standard for self segmented use (color can be used to distinguish its length).

---When clamping the front upper, special attention must be paid to aligning the upper part with the last, not tilting, and at the same time, fixing the standard height of the heel first.

---When clamping the middle upper, pay attention to whether the upper of both waists is truly tightened, and the tension should be moderate and even.

---When clamping the back upper, attention should be paid to whether the heel height meets the standard. If the heel height of each shoe has a mark that meets the last heel standard, the finished shoe will not have an inconsistent height between the left and right feet. After the last is finished, the midsole nail should be removed to facilitate the last removal and avoid injuring the foot when wearing shoes.

---A quality inspector should be appointed for the upper clamping process to manually adjust and remedy poor upper clamping.

8. Rubbing and pasting to form the bottom

---Pay attention to the accuracy of the marking board, so that the air pressure is about 0. 6MPa;

---Coarse grinding requires removing the paint on the leather surface according to the marked arc.

---The bonding surface of the large bottom must be treated with a solution of medicine.

---The heating should be around 100 ℃± 5 ℃.

---Before applying the sole, attention should be paid to the correctness and uniformity of the glue applied to the shoe upper and sole, and it should not contaminate the shoe upper and sole;

---When the shoe upper fits the sole of the shoe, employees must pay attention to not tilting the sole. For shoes with edges, it is advisable to use an airbag or three-dimensional block press to press the sole.

---When pressing the sole, operators should pay attention to the correctness of the press and control the pressing time (5-8S) and pressure (20-40KN).

---After pressing the sole, sulfur-adding shoes: shoes must be collected and placed in a sulfur-adding tank for sulfur shaping; Cold adhesive shoes: Shoes must be placed in a freezer for freezing and shaping. 9. It is best not to remove the last of the shoe before it has completely cooled and formed on the last after pressing the sole, to avoid deformation of the shoe.

9. Package

---After removing the last, the shoes must undergo preliminary cleaning both inside and outside;

---For those that require spray finishing, the spray agent should be properly mixed, and the spray should be uniform and able to highlight the key points;

---Insert the insole and properly glue it firmly;

---Finally, clean and organize the shoelaces, and put them into the toe-filling paper;

---Final quality inspection

---Put into shoe box or plastic bag

---Packing

10. Other equipment required for the shoe production line

 

The knife mold used for cutting and cutting materials is designed according to the shoe shape and manufactured according to standardized cardboard;

 

Forming lasts can be divided into plastic lasts and aluminum lasts. Generally, the production of cold adhesive shoes is more economical due to changes in the last shape. For sports shoes or large quantities of casual shoes, aluminum lasts are preferred. 

 

The quality inspection personnel of the clamping group and the sample room personnel use bird beak pliers, and 8-10 pieces must be prepared for each molding production line;

 

Punching molds are used for punching shoe eyelets, and cardboard is used to create them according to the shoe upper design standards. When clamping the upper, the arch is used to fix the heel width, and it is segmented according to the shoe size according to the shoe shape design;

 

Steel wire wheels are used for roughening, nylon brushes are used for debonding, and miscellaneous equipment such as manual roughening machines, decontamination spray guns, and marker pens are used;

 

Hand roughening machine, decontamination spray gun, marking pen and other miscellaneous equipment;