Preparation method of multi-type multi-granularity combined abrasive belt

Abstract

The invention relates to the technical field of grinding machining, in particular to a preparation method of a multi-type and multi-granularity combined abrasive belt. The preparation method comprises the steps that partition plates are arranged in a sand box of electrostatic sand planting equipment to form independent compartments, and abrasive materials with different granularities or types are contained in the independent compartments; the base material coated with the primer is conveyed to an electric field area, and the compartment abrasive materials are planted in the corresponding areas of the base material; sequentially carrying out pre-drying, compound glue coating, main drying and curing treatment; the distance between the cutters is adjusted according to the distance between the partition plates, and the abrasive cloth is cut into abrasive belts. Multi-granularity / type grinding material combination is achieved through the partition plates, the diversified machining requirements are met, and the machining precision is improved; abrasive distribution is accurately controlled, the sand planting process is optimized, and the production quality and stability are improved; the abrasive belt strength is enhanced, and the adhesive layer performance is optimized; the production process is simplified, different product requirements are met, and the production efficiency and flexibility are improved; the grinding material meets the standard, process parameters are controllable, stable product quality is guaranteed, and the method is suitable for various machining scenes and has wide market application prospects.

Description

Technical Field

[0001] The invention relates to the technical field of grinding processing, in particular to a method for preparing a multi-type and multi-grain size combined abrasive belt. Background Art

[0002] In modern industrial processing, abrasive belts, as a crucial grinding tool, are widely used in a variety of industries, including metalworking, woodworking, and stone processing. As industrial production demands ever-increasing precision and efficiency, higher performance requirements are placed on abrasive belts. Traditional abrasive belts typically utilize a single abrasive size or type, making them difficult to meet the differentiated demands of different grinding areas in complex processing scenarios.

[0003] Most existing sanding belt preparation technologies use abrasives of a single particle size, which can only meet single processing requirements. It is impossible to achieve continuous operation of different processing stages such as coarse grinding and fine grinding on the same sanding belt, resulting in the need to frequently replace the sanding belt when processing complex workpieces, reducing production efficiency and increasing production costs.

[0004] The comparative document CN106584286B (a preparation process of a super-hard abrasive sanding belt and a super-hard abrasive sanding belt) mainly involves a method for preparing a sanding belt using super-hard abrasives such as diamond or cubic boron nitride (CBN). Its core process includes abrasive surface modification, composite electroplating sand planting, high-temperature curing and other steps. Although this technology has certain advantages in the application of high-hardness abrasives, it only uses a single super-hard abrasive (such as diamond or CBN) and cannot achieve gradient processing from coarse grinding to fine grinding on the same sanding belt. The super-hard abrasive is fixed by the composite electroplating method, and the uniformity of the abrasive distribution is affected by the concentration of the electroplating solution and the current density. The edge area is prone to uneven abrasive density (measured density fluctuation ≥15%). Summary of the Invention

[0005] The object of the present invention is to provide a method for preparing a multi-type and multi-grain size composite abrasive belt to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A method for preparing a multi-type and multi-grain size composite abrasive belt comprises the following steps:

[0008] S10: a partition is set in the sand box of the electrostatic sand planting equipment to form an independent compartment, and each compartment is filled with abrasives of different particle sizes or types;

[0009] S20: transporting the base material coated with the primer to the electric field area through the sand planting belt, and planting the abrasives in each compartment on the corresponding area of the base material through the electric field force;

[0010] S30: Pre-drying, re-sizing, main drying and curing are performed in sequence to form a multi-size / type combined abrasive cloth;

[0011] S40: adjusting the cutter spacing of the stripping and trimming equipment according to the partition spacing ratio, and cutting the abrasive cloth into abrasive belts with a predetermined particle size / type distribution combination.

[0012] Preferably, in step S10, a plurality of partitions are installed in the sandbox, and both sides of the partitions are fixed to the inner wall of the sandbox by bolts. The ratio of the compartment width to the designed partition width of the abrasive belt is 1:1 or 2:1, which helps to accurately control the width of different abrasive partitions on the abrasive belt and ensure that each partition is accurately distributed according to the design requirements. The ratio of 1:1 can achieve a complete correspondence between the partition width and the compartment width, and the ratio of 2:1 provides more flexible partition design options to meet the requirements of abrasive distribution density under different processing needs, thereby ensuring that the abrasive belt performs optimally in different areas.

[0013] Preferably, the partition is made of 304 stainless steel plate with a thickness of 1-2mm. 304 stainless steel has good strength and corrosion resistance. The design of 1-2mm thickness can ensure that the partition can withstand the weight of the abrasive and the impact force during the sanding process in the sand box without being easily deformed, and can also avoid increasing the overall weight of the sand box and occupying too much space due to the partition being too thick.

[0014] Preferably, a reciprocating inclined plate and a speed control plate are installed at the bottom of each compartment of the sand box. A reciprocating hydraulic cylinder for controlling the reciprocating inclined plate and a servo electric cylinder for controlling the speed control plate are respectively installed on the outer walls of the sand box. The reciprocating inclined plate evenly distributes the abrasive within the compartment, preventing abrasive accumulation in a single area and ensuring uniform sand discharge. The speed control plate precisely controls the speed of abrasive discharge, adjusting the amount of sand discharged according to the characteristics of the different abrasives and the sand planting requirements, thereby improving the sand planting quality.

[0015] Preferably, the electrostatic sand planting parameters in step S20 are: AC voltage 30-48kV, frequency 4-10Hz, sand planting belt speed 2-5m / min, and sand gap width under the sand box 1000-4000μm. Accurate sand planting parameter control helps to reduce problems such as uneven sand planting and abrasive shedding caused by parameter fluctuations, improve the product quality stability of the sand belt, and ensure that the sand belt has consistent grinding performance during use.

[0016] Preferably, the base glue comprises 40-100 parts phenolic resin, 0-60 parts chalk, and 0-5 parts additive, with a viscosity of 200-3000 cp; the secondary glue comprises 30-100 parts phenolic resin, 0-70 parts chalk, 0-70 parts cryolite, and 0-5 parts additive, with a viscosity of 100-5000 cp. The rational proportions of phenolic resin, chalk, cryolite, and additives in the base and secondary glues provide excellent bonding properties, allowing the abrasive to firmly adhere to the substrate. Phenolic resin, as the primary bonding component, imparts sufficient strength and toughness to the adhesive layer; the addition of fillers such as chalk and cryolite can adjust the properties of the adhesive layer, such as reducing costs and improving wear resistance.

[0017] Preferably, in step S30, the pre-drying temperature is 80-110°C for 70-110 minutes, the main drying temperature is 50-120°C for 90-130 minutes, and the curing temperature is 120-140°C for 3-10 hours. The temperature and time ranges for the pre-drying, main drying, and curing processes are determined based on the properties of the adhesive and the heat resistance of the substrate. A reasonable combination of temperature and time allows the adhesive layer to fully cure, developing excellent physical and chemical properties, ensuring a strong bond between the abrasive and the substrate, and extending the life of the abrasive belt.

[0018] Preferably, the abrasive is selected from one or more of brown corundum, ceramic corundum, zirconium corundum, the particle size span does not exceed 5 particle size numbers, and complies with GB / T2481 standard. The substrate is pure cotton cloth, polyester cloth or steel paper, and the primer coating amount is 20-500g / m 2 The sizing is applied by a rubber roller coating method. The appropriate abrasive combination can be selected according to the material characteristics and processing requirements of the workpiece to achieve a variety of grinding effects. The base material is made of pure cotton cloth, polyester cloth or steel paper, providing different strength, flexibility and wear resistance options to adapt to different processing scenarios.

[0019] Preferably, in step S40, the strip cutting is performed using an extruded disc knife with a cutting speed of 10-20 m / min. The cutter spacing is kept in a 1:1 correspondence with the sand box partition spacing, which helps to reduce burrs and deformation on the edge of the sanding belt, improve the appearance quality and dimensional accuracy of the sanding belt, and ensure that the sanding belt can operate stably and reliably during use.

[0020] Preferably, the sanding belt comprises at least two abrasive partitions, and the width error of each partition boundary is ≤1mm. The 180° peeling test shows that the substrate is broken or the adhesive layer is completely detached. When the substrate is polyester cloth, the finished sanding belt is tested to have a maximum tensile force ≥1800N / 5cm and an elongation at break ≤20%. The 180° peeling test shows that the substrate is broken or the adhesive layer is completely detached, indicating that the bonding strength between the abrasive and the substrate is high, and the abrasive is not prone to falling off during use. When the substrate is polyester cloth, the finished sanding belt is tested to have a maximum tensile force ≥1800N / 5cm and an elongation at break ≤20%, indicating that the sanding belt has good mechanical properties, can withstand large tension and deformation without damage, is suitable for various high-intensity processing scenarios, and improves the reliability and service life of the sanding belt.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. Realize the combination of multiple particle sizes / types of abrasives

[0023] Meeting diverse processing needs: By installing partitions within the sandbox to create independent compartments, each containing abrasives of different grit sizes or types, multiple abrasives can be flexibly combined based on the material properties, shape, and processing requirements of the workpiece, achieving targeted grinding effects in different areas during a single operation. For example, for workpieces with both rough and fine surfaces, coarse and fine abrasives can be set in different areas of the sanding belt to improve processing efficiency and quality.

[0024] Improve machining accuracy: The reasonable combination of abrasives of different particle sizes or types helps to better control factors such as grinding force and grinding heat during the machining process, reduce problems such as burning and deformation on the workpiece surface, and thus improve machining accuracy and surface quality.

[0025] 2. Improve the quality and stability of abrasive belt production

[0026] Precisely control abrasive distribution: Different abrasives are separated by partitions, and the abrasives in each compartment are planted in the corresponding area of the substrate through the electric field force. The distribution position and range of the abrasive on the substrate can be precisely controlled to ensure that the width error of each partition boundary is ≤1mm, ensuring the accuracy and consistency of the abrasive distribution on the sanding belt and improving the stability of product quality.

[0027] Optimize the sand planting process: A reciprocating inclined plate and a speed control plate are installed at the bottom of the sand box, which are controlled by a reciprocating hydraulic cylinder and a servo electric cylinder respectively. The sand feeding speed and uniformity can be accurately adjusted according to the characteristics of different abrasives and sand planting requirements, avoiding the problem of abrasive accumulation or uneven distribution, and further improving the sand planting quality.

[0028] 3. Enhance the performance of the sanding belt

[0029] Improved belt strength: 180° peel tests revealed either base material breakage or complete detachment of the adhesive layer, demonstrating a strong bond between the abrasive and base material. This prevents abrasive shedding during use, extending the belt's lifespan. When the base material is polyester cloth, the finished belt demonstrated a maximum tensile force of ≥1800N / 5cm and an elongation at break of ≤20%, demonstrating excellent mechanical properties. The belt can withstand significant tensile forces and deformation without damage, making it suitable for a variety of high-intensity machining scenarios.

[0030] Optimizing adhesive layer performance: A well-balanced base and top coat formulation, along with a precise coating process, ensures the adhesive layer retains abrasives effectively and provides excellent flexibility and wear resistance. The combination of different ingredients in the base and top coat helps adjust adhesive layer properties, such as viscosity and curing speed, to meet diverse production conditions and processing requirements.

[0031] 4. Improve production efficiency and flexibility

[0032] Simplified production process: The present invention integrates the combination of multi-size / type abrasives and the sand planting process into one electrostatic sand planting device, avoiding the tedious process of multiple abrasive replacements and complex operations required in traditional processes, greatly improving production efficiency.

[0033] Adapt to different product needs: By adjusting the spacing ratio of the partitions and the cutter spacing of the stripping and trimming equipment, abrasive belts with different particle size / type distribution combinations can be easily produced to meet the diverse product needs in the market and improve the company's market competitiveness.

[0034] 5. Comply with standards and quality control

[0035] Abrasives meet standards: Abrasives are selected from one or more of brown corundum, ceramic corundum, and zirconium corundum. The particle size span does not exceed 5 particle sizes and meets the GB / T2481 standard, ensuring the quality and stable performance of the abrasives and providing a basis for the production of high-quality sanding belts.

[0036] Controllable process parameters: The key process parameters such as electrostatic sand planting parameters (AC voltage, frequency, sand planting belt speed, sand box lower sand gap width), pre-drying, main drying and curing treatment temperature and time are clearly specified, making the production process repeatable and controllable, which is conducive to ensuring the stability and consistency of product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they provide further detailed explanation, but do not constitute a limitation of the present invention.

[0038] Figure 1 It is a structural diagram of the sand box of the present invention;

[0039] Figure 2 Schematic diagram of the cross-sectional structure of the sand box of the present invention;

[0040] The meaning of the symbols in the figure:

[0041] 10. Sand box; 11. Reciprocating hydraulic cylinder; 12. Servo electric cylinder; 20. Partition; 30. Bolt; 40. Reciprocating inclined plate; 50. Speed control plate. DETAILED DESCRIPTION

[0042] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0043] Example 1

[0044] 1. Materials and Equipment Preparation

[0045] Abrasive: Brown corundum (grain size P60) and ceramic corundum (grain size P40) are selected. The particle size span of the two is 2 particle sizes, which conforms to the GB / T2481 standard.

[0046] Base material: Choose blended cloth or polyester cloth, the primer coating amount is 250, the primer formula can be 30 parts of phenolic resin, 20 parts of chalk, 1 part of additive, and the viscosity is 1500cp.

[0047] Sand box partition: Install several groups of 1mm thick 304 stainless steel plates as partitions. The two sides of the partitions are fixed to the inner wall of the sand box by bolts. The ratio of the compartment width to the designed partition width of the sanding belt is 1:1.

[0048] Sand box bottom device: A reciprocating inclined plate and a speed control plate are installed at the bottom of each compartment, and a reciprocating hydraulic cylinder for controlling the reciprocating inclined plate and a servo electric cylinder for controlling the speed control plate are installed on the outer walls on both sides of the sand box respectively.

[0049] 2. Preparation steps

[0050] S10: Setting up compartments and loading materials: Independent compartments are formed in the sand box of the electrostatic sand planting equipment through partitions, and brown corundum and ceramic corundum abrasives are loaded into each compartment respectively.

[0051] S20 electrostatic sand planting: The pure cotton substrate coated with primer is transported to the electric field area through the sand planting belt. The voltage is 37kv and the sanding gap is 2500 microns. The abrasives in each compartment are planted in the corresponding area of the substrate through the electric field force.

[0052] S30 Post-Processing: Pre-drying is performed sequentially at 90°C for 70 minutes. The adhesive compound formula remains unchanged, with a viscosity of 1000 cp, a temperature of 90°C, and a time of 90 minutes. Curing is then performed at 120°C for 3 hours to form a multi-grit composite abrasive cloth. S40 Slitting and Trimming: The spacing of the extruded disc blades of the slitting and trimming equipment is adjusted according to the ratio of the partition spacing. The cutting speed is 10 m / min, and the blade spacing is maintained in a 1:1 relationship with the sandbox partition spacing. The abrasive cloth is then cut into abrasive belts with a predetermined particle size distribution.

[0053] 3. Performance Testing

[0054] The abrasive belt contains two abrasive partitions, and the width error of each partition boundary is 0.8mm.

[0055] After 180° peel test, the substrate broke.

[0056] When the base material is pure cotton cloth, the relevant mechanical properties of the finished abrasive belt meet the requirements.

[0057] Example 2

[0058] 1. Materials and Equipment Preparation

[0059] Abrasive: Ceramic corundum (particle size P120) and zirconium corundum (particle size P60) are selected, with a particle size span of 3 sizes, in line with GB / T2481 standard.

[0060] Base material: Polyester cloth, primer coating amount is 180g / m 2 , the glue is applied by rubber roller coating.

[0061] Sand box partition: Install 1.5mm thick 304 stainless steel plate partition, and the ratio of the compartment width to the sanding belt design partition width is 2:1.

[0062] Sand box bottom device: same as embodiment 1.

[0063] 2. Preparation steps

[0064] S10: Setting up compartments and loading materials: using partitions to form independent compartments in the sand box, and loading ceramic corundum and zirconium corundum abrasives respectively.

[0065] S20 electrostatic sand planting: The polyester substrate coated with primer is transported to the electric field area through a sand planting belt. The electrostatic sand planting parameters are AC voltage 40kV, frequency 6hz, and sanding gap 2000 microns. The primer may include 60 parts of phenolic resin, 20 parts of chalk, 1 part of additives, and a viscosity of 700cp, so that the abrasive is planted in the corresponding area of the substrate.

[0066] S30 post-treatment: pre-drying temperature 95℃, time 90min; the adhesive contains 60 parts of phenolic resin, 35 parts of chalk, 30 parts of cryolite and 3 parts of additives, with a viscosity of 600cp; the main drying temperature is 85℃, time 110min; the curing temperature is 130℃, time 6h.

[0067] S40 Slitting and trimming: Adjust the cutter spacing, cutting speed 15m / min, and cut the abrasive cloth in a 1:1 ratio.

[0068] 3. Performance Testing

[0069] The error in the width of the sand belt partition boundary is 0.9mm.

[0070] The 180° peel test showed that the adhesive layer was completely detached.

[0071] When the base material is polyester cloth, the maximum tensile force of the finished abrasive belt is 3000N / 5cm and the elongation at break is 16%.

[0072] Example 3

[0073] 1. Materials and Equipment Preparation

[0074] Abrasive: Brown corundum (grit size P80), ceramic corundum (grit size P180), with a grit range of 4 sizes, in line with the standard.

[0075] Base material: steel paper, primer coating amount 160g / m 2 , apply glue with rubber roller.

[0076] Sand box partition: 2mm thick 304 stainless steel plate, the ratio of compartment width to partition width is 1:1.

[0077] Sand box bottom device: same as embodiment 1.

[0078] 2. Preparation steps

[0079] S10: Setting up compartments and loading materials: two types of abrasives are loaded into the compartments in the sand box respectively.

[0080] S20 electrostatic sand planting: AC voltage 40kV, frequency 8Hz, sand planting belt speed 5m / min, sand gap width 1800μm.

[0081] S30 post-treatment: pre-drying temperature 80℃, time 70min, base glue contains 100 parts of phenolic resin, 60 parts of chalk, and 2 parts of additives; double glue contains 100 parts of phenolic resin, 40 parts of chalk, 60 parts of cryolite, and 5 parts of additives, main drying temperature 80℃, time 100min.

[0082] S40 slitting and trimming: cutting speed 20m / min, cutter spacing and partition spacing 1:1 corresponding cutting.

[0083] The partition boundary width error is 1mm.

[0084] The substrate broke in the 180° peel test.

[0085] The performance of the abrasive belt with steel paper substrate meets the relevant requirements.

[0086] Comparative Example 1

[0087] 1. Materials and Equipment Preparation

[0088] Abrasive: Only brown corundum (particle size P60) is used as an abrasive, which does not meet the requirement of at least two abrasives in the invention.

[0089] Base material: polyester cloth, primer coating amount 100g / m 2 .

[0090] Sand box partition: No partition is set, and no independent compartment is formed in the sand box.

[0091] Other equipment: Same as Example 2.

[0092] 2. Preparation steps

[0093] S10: No partition is set in the sand box, and a single abrasive is directly loaded.

[0094] S20: The electrostatic sand planting parameters are AC voltage 30 kV, frequency 4 Hz, sand planting belt speed 2 m / min, and sand gap width 1000 μm.

[0095] S30: Pre-drying at 80°C for 70 minutes; adhesive layer containing 30 parts phenolic resin and 20 parts chalk, with a viscosity of 100 cps; main drying at 50°C for 90 minutes; curing at 120°C for 3 hours. S40: Slitting and trimming at a cutting speed of 10 m / min.

[0096] 3. Performance Testing

[0097] The abrasive belt has only one abrasive partition and cannot form a multi-grain size combination.

[0098] 180° peel test: The adhesive layer is partially detached.

[0099] When the substrate is polyester cloth, the maximum tensile force is 1500 N / 5 cm and the elongation at break is 25%, which is inferior to that of Example 2.

[0100] Comparative Example 2

[0101] 1. Materials and Equipment Preparation

[0102] Abrasives: brown corundum (grain size P40) and ceramic corundum (grain size P150), with a grain size span of 6 grain sizes, exceeding the requirement in the invention that the grain size span does not exceed 5 grain size numbers.

[0103] Base material: pure cotton cloth, primer coating amount 100g / m 2 .

[0104] Sand box partition: The ratio of compartment width to partition width is set to 3:1, which does not comply with the 1:1 or 2:1 ratio in the invention.

[0105] Other equipment: Same as Example 1.

[0106] 2. Preparation steps

[0107] S10: A partition is set in the sand box with a compartment width to partition width ratio of 3:1, and two types of abrasives are loaded.

[0108] S20: Electrostatic sand planting parameters: AC voltage 48kV, frequency 10Hz, sand planting belt speed 5m / min, sand gap width 4000μm.

[0109] S30: Pre-drying temperature 110°C, time 110 minutes; the adhesive contains 100 parts of phenolic resin, 60 parts of chalk, and 70 parts of cryolite, with a viscosity of 5000cp; the main drying temperature is 120°C, time 130 minutes; the curing temperature is 140°C, time 10 hours.

[0110] S40: Slitting and trimming cutting speed 20m / min.

[0111] 3. Performance Testing

[0112] The error in the width of the abrasive belt partition boundary is 1.5 mm, exceeding the requirement of ≤1 mm in the invention.

[0113] Abrasive shedding occurred during the 180° peel test.

[0114] When the substrate is pure cotton cloth, the relevant performance indicators are not as good as those in Example 1.

[0115] Comparison table of key parameters and results of the above three embodiments:

[0116] Group Number of abrasive partitions Partition boundary width error 180° peel test results Substrate type Maximum tensile strength (N / 5cm) Elongation at break (%) Example 1 2 0.8mm Substrate fracture pure cotton cloth -(Meets the requirements) -(Meets the requirements) Example 2 2 0.9mm The adhesive layer is completely detached Polyester cloth 1900 18 Example 3 2 1mm Base material fracture Steel paper -(Meets the requirements) -(Meets the requirements) Comparative Example 1 1 Partial detachment of the adhesive layer Polyester cloth 1500 25 Comparative Example 2 2 1.5mm Abrasive shedding pure cotton cloth -(Not meeting the standard) -(Not meeting the standard)

[0117] 1. Achieve precise distribution of abrasives of multiple sizes and types

[0118] The partitioning is precise and controllable: by setting partitions in the sand box to form independent compartments, abrasives of different particle sizes or types can be implanted in the corresponding areas of the substrate. For example, Examples 1-3 all achieve precise distribution of at least two abrasive partitions, and the error in the width of each partition boundary is ≤1mm (the error in Example 1 is 0.8mm, the error in Example 2 is 0.9mm, and the error in Example 3 is 1mm). However, since Comparative Example 2 does not set the partition spacing ratio as required by the invention, the error in the width of the partition boundary reaches 1.5mm, which exceeds the standard, fully demonstrating the advantage of the invention in the accuracy of abrasive partitioning.

[0119] Meeting diverse needs: Different abrasives (such as brown corundum, ceramic corundum, and zirconium corundum) can be flexibly combined according to actual needs, and the particle size span does not exceed 5 particle size numbers, so that the sanding belt can adapt to different grinding scenarios. In contrast, Example 1 only uses a single abrasive and cannot form a multi-particle size combination, which limits the application scenarios.

[0120] 2. Scientific and reasonable production process to improve the quality of sanding belt

[0121] Optimization of electrostatic sand planting parameters: setting parameters such as AC voltage 30-48kV, frequency 4-10Hz, and sand planting belt speed 2-5m / min, and coordinating the sand gap width under the sand box to 1000-4000μm, so that the abrasive can be evenly and firmly planted on the substrate under the action of the electric field force. Compared with the control example where the parameter range was not strictly followed, the sand planting effect was significantly improved.

[0122] The post-processing process is perfect: the temperature and time settings of pre-drying, re-coating, main drying and curing treatment are reasonable. For example, in Example 2, the pre-drying temperature is 95°C and the time is 90 minutes, the main drying temperature is 85°C and the time is 110 minutes, and the curing temperature is 130°C and the time is 6 hours, ensuring that the adhesive layer is tightly bonded to the abrasive and the substrate. However, in Comparative Example 1, due to unreasonable process parameter settings, the adhesive layer partially detached in the 180° peeling test. The invented process can effectively ensure the bonding strength of the sanding belt.

[0123] 3. Excellent abrasive belt performance and outstanding mechanical properties

[0124] Good peeling performance: Examples 1 and 3 showed substrate fracture in the 180° peeling test, and Example 2 showed complete detachment of the adhesive layer, both of which met the ideal peeling test results, indicating that the bonding force between the adhesive layer and the substrate and abrasive was strong; while Comparative Example 1 showed partial detachment of the adhesive layer, and Comparative Example 2 even showed abrasive falling off, indicating that the technical solution of the invention can significantly improve the peeling performance of the sanding belt.

[0125] High mechanical strength: When polyester cloth is used as the base material, the maximum tensile force of the finished abrasive belt of Example 2 reaches 1900N / 5cm, and the elongation at break is ≤18%, which is better than 1500N / 5cm and 25% of the elongation at break of Comparative Example 1, reflecting the obvious advantages of the invention in the mechanical properties of the abrasive belt. In particular, when the base material is polyester cloth, the requirement of maximum tensile force ≥1800N / 5cm is met, ensuring that the abrasive belt is not easy to break during use and has strong durability.

[0126] 4. The equipment is cleverly designed and easy to operate

[0127] Optimized sand box structure: The partitions are made of 1-2mm thick 304 stainless steel plates and are fixed to the inner wall of the sand box by bolts. The ratio of the compartment width to the designed partition width of the sand belt is 1:1 or 2:1, which ensures the accuracy of the abrasive partitioning. The reciprocating inclined plate and speed control plate installed at the bottom of each compartment of the sand box, combined with the reciprocating hydraulic cylinder and servo electric cylinder control, can accurately adjust the falling speed and distribution of the abrasive, making the sand planting process more stable and controllable.

[0128] Precise slitting and trimming: The cutter spacing of the slitting and trimming equipment is adjusted according to the ratio of the partition spacing, and maintains a 1:1 correspondence with the sand box partition spacing. For example, the cutting speed in the embodiment is 10-20m / min, which ensures that the sanding belt can accurately present the predetermined particle size / type distribution combination after slitting, thereby improving the accuracy and efficiency of production.

[0129] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely preferred examples of the present invention and are not intended to limit the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and improvements fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a multi-type and multi-size composite abrasive belt, characterized by: The following steps are involved: S10: a partition is set in the sand box of the electrostatic sand planting equipment to form an independent compartment, and each compartment is filled with abrasives of different particle sizes or types; S20: transporting the base material coated with the primer to the electric field area through the sand planting belt, and planting the abrasives in each compartment on the corresponding area of the base material through the electric field force; S30: Pre-drying, re-sizing, main drying and curing are performed in sequence to form a multi-size / type combined abrasive cloth; S40: adjusting the cutter spacing of the stripping and trimming equipment according to the partition spacing ratio, and cutting the abrasive cloth into abrasive belts with a predetermined particle size / type distribution combination.

2. The method for preparing a multi-type and multi-grain size composite abrasive belt according to claim 1, characterized in that: In step S10, a plurality of partitions (20) are installed in the sand box (10), and both sides of the partitions (20) are fixed to the inner wall of the sand box (10) by bolts (30). The ratio of the partition width to the designed partition width of the sand belt is 1:1 or 2:

1.

3. The method for preparing a multi-type and multi-grain size composite abrasive belt according to claim 2, characterized in that: The partition (20) is made of 304 stainless steel plate with a thickness of 1-2 mm.

4. The method for preparing a multi-type and multi-grain size composite abrasive belt according to claim 3, characterized in that: A reciprocating inclined plate (40) and a speed control plate (50) are installed at the bottom of each compartment of the sand box (10), and a reciprocating hydraulic cylinder (11) for controlling the reciprocating inclined plate (40) and a servo electric cylinder (12) for controlling the speed control plate (50) are respectively installed on the outer walls of both sides of the sand box (10).

5. The method for preparing a multi-type and multi-grain size composite abrasive belt according to claim 1, characterized in that: The electrostatic sand planting parameters in step S20 are: AC voltage 30-48 kV, frequency 4-10 Hz, sand planting belt speed 2-5 m / min, and sand gap width under the sand box 1000-4000 μm.

6. The method for preparing a multi-type and multi-grain size composite abrasive belt according to claim 1, characterized in that: The base glue contains 40-100 parts of phenolic resin, 0-60 parts of chalk and 0-5 parts of additives, with a viscosity of 200-3000cp; the secondary glue contains 30-100 parts of phenolic resin, 0-70 parts of chalk, 0-70 parts of cryolite and 0-5 parts of additives, with a viscosity of 100-5000cp.

7. The method for preparing a multi-type and multi-grain size composite abrasive belt according to claim 1, characterized in that: In step S30, the pre-drying temperature is 80-110°C / 70-110 minutes, the main drying temperature is 50-120°C / 90-130 minutes, and the curing temperature is 120-140°C / 3-10 hours.

8. The method for preparing a multi-type and multi-grain size composite abrasive belt according to claim 1, characterized in that: The abrasive is selected from one or more of brown corundum, ceramic corundum, and zirconium corundum, with a particle size span of no more than 5 particle sizes and in compliance with GB / T2481 standard. The substrate is pure cotton cloth, polyester cloth or steel paper, and the primer coating amount is 20-500g / m 2 , the glue is applied by rubber roller coating.

9. The method for preparing a multi-type and multi-grain size composite abrasive belt according to claim 1, characterized in that: In step S40, the strip cutting is performed using an extrusion disc knife with a cutting speed of 10-20 m / min. The distance between the cutters and the distance between the sand box partitions maintains a 1:1 correspondence.

10. The method for preparing a multi-type and multi-grain size composite abrasive belt according to claim 1, characterized in that: The abrasive belt comprises at least two abrasive partitions, and the width error of the boundary of each partition is ≤1mm. A 180° peeling test shows that the substrate is broken or the adhesive layer is completely detached. When the substrate is polyester cloth, the finished abrasive belt is tested to have a maximum tensile force of ≥1800N / 5cm and an elongation at break of ≤20%.

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