1. Feed control
Quality control begins with acceptance of raw materials such as adhesives and catalysts. The purchase order is generally required to specify the required quality performance of the feed, which is given in the actual requirements entry or material description.
(1) Package: The first thing to check is the case of the package. The contents of the inspection should include the following items:
Damage: The physical damage to the plastic packaging box causes the sealing strip to crack and the moisture and dust will enter the box and contaminate the film. Damage to the package will also prevent a barrel of glue from being metered on the automatic measuring device.
Leakage situation - If the box is equipped with a matching adhesive, the leakage of the adhesive components will change the ratio of the catalyst to the resin and also cause the loss of the adhesive.
The situation of the sign - the people of the package should include: product name; storage period; manufacturer name; recommended storage conditions; production date; instructions for use; batch number; safety issues.
(2) Adhesives: Adhesive inspections purchased should include Class II tests. Physical tests such as fluidity, gel time, and volatilization rate are all parameters that technicians are most concerned with to ensure the quality of the bond. Adhesive fluidity is one example of this and is important in the bonding process. Adhesive fluidity can not be too large, otherwise it will cause glue layer lack of glue; fluidity can not be too small, otherwise it will make the glue layer too thick, or glue can not be completely filled with glue. Methods for determining physical properties include:
The ASTM method for measuring physical properties includes D816, D898, D899, D1084, D1337, D1448, D1489, D1490, D1579, D1582, D1583, D1584, D1875, D1916, D2183, D2556, D2979, D3121, D3236.
(3) Mechanical properties of adhesives: The mechanical properties of adhesives are of great concern because they determine the structural strength of the finished product. Test methods for the mechanical properties of adhesives include standard test methods for durability, flexibility, and fatigue.
ASTM mechanical properties test methods are ASTM D897, D903, D905, D906, D950, D1002, D1062, D1144, D1184, D1344, D1781, D1876, D2095, D2182, D2295, D2339, D2557, D2558, D2918, D2919, D3111, D3163 , D3164, D3165, D3166, D3167, D3527, D3528, D3568, D3702, D3807, D3808, D3931, D4027, E229.
(4) Other properties of adhesives (including creep): Other test methods for adhesives are: ASTM D896, D904, D1146, D1151, D1174, D1183, D1286, D1304, D1382, D1383, D1581, D1713, D1780, D1828, D1877, D1879, D2294, D2739, D3310, D3632, D3929.
2. Surface treatment control After the feed quality is determined, the second process is the surface treatment of the adherend. In order to make the adhesive quality reliable, the surface treatment must be carefully controlled.
If the surface needs chemical treatment, the heart must control the proper procedures, soak temperature, solution concentration and contamination. If blasting is used, sand should be changed regularly. Solvent wipes should have enough clean cloth, fresh solvent for cleaning, and always check if the cloth or solvent container is contaminated. The effect of the surface treatment can be verified by the water film failure test. After the final treatment of the surface treatment, the surface was coated with deionized water and the adherent surface was examined for its ability to form a continuous water film. If it is considered that the surface treatment can meet the requirements, the surface should be kept clean and dry before bonding, and the primer should be coated on the treated surface as soon as possible.
3. Adhesion process control In addition to the above-mentioned adherend surface treatment to be controlled, the bonding process including pre-mating, gluing, assembly, and curing is also controlled.
(1) Pre-coordination: All the parts to be glued should be assembled together before gluing to check if they can be in close contact. If two or more parts are not pre-fitted prior to bonding, it may be difficult to ensure good bonding joints due to poor adhesion. If it is a highly efficient and repeatable production and the assembly accuracy is guaranteed, the pre-mating process can sometimes be omitted. The fit of the initial product can be checked with an anti-ablative film that can generate a mark, which can greatly reduce the risk of poor assembly of expensive or critical components. When there is no problem with pre-mating, mark each bonded part in the pre-match so that the parts can be assembled easily after gluing. The process control test pieces, ie the remaining parts with labels in the assembly, shall be placed together with the set of pre-mated parts to be adhered and shall be examined during the pre-match inspection. These process control test pieces must go through each process as well as the finished product. After curing, test the test pieces to determine whether the adhesive and surface treatment and other process conditions of the lot meet the requirements.
(2) Gluing: Most structural adhesive films need to be primed when used, and primers are usually sprayed with air or without air. Roller or brush can be used when the area is small or no spraying equipment. The undercoat must be air-dried, and some must be dried to remove the solvent. Usually the thickness of the primer will affect the bond strength, so it should be controlled and tested, usually by checking the glue applicator regularly and measuring the thickness of the dried primer.
Before the film adhesive is applied, remove the paper or plastic protection/isolation film, and then lay the film on the adhesive surface. Be careful not to wrinkle, otherwise it will trap air. A common operation error is that the separator is not removed when the parts to be bonded are assembled, and some bonding operators use special inspection heads to ensure that the separator is torn off. In the inspection record, the type of adhesive, batch number, group number, and time and date of gluing should be included for future reference when damage occurs. Also record the end of the pot life, which is useful for controlling assembly and adhesive curing.
(3) Assembling: The glued parts are often glued together with a tool or holding device. The cleanliness and suitability of the tool should be checked. The effective time of the surface treatment, the pot life of the adhesive and the holding time of the adhesive curing are checked during assembly.
Also check that the parts to be glued are assembled in the correct order and fit. It is important to keep clean and adjust the humidity of the air. Parts and adhesives are exposed to the control from the preparation of the adhesive until the initial curing. Operational situation control usually includes the following aspects:
1, the temperature is maintained at 18-320C
2, relative humidity to maintain 20-65%;
3. The incoming air must be filtered to prevent the operating space from being contaminated;
4. Make the operating space slightly different from the surrounding environment. The above conditions can be detected with a recording temperature and humidity indicator.
(4) Curing: The curing of adhesive in any joint is a function of time-temperature-pressure. The length of curing time can be controlled by manual timing or automatic timing device. The detection is usually based on the temperature and/or pressure recorder curing chart, while recording the temperature and pressure.
The specified curing temperature always refers to the temperature of the adhesive layer. Because the adhesive has poor heat transfer, it must be added for a period of time to allow heat to be transferred to the adhesive layer. In addition, heating fixtures also take up most of the curing cycle.
The heat source must ensure the required heat and uniformity when curing, and must consider the following factors:
1, heating rate;
2, the maximum temperature;
3, temperature range or coverage when heated and cured;
4, cooling cooling characteristics.
(5) Standard test piece: It is best to make a standard test piece and go through the same process with the adhered parts. Standard test pieces should be designed for test methods that represent the requirements of the main structure for loading. For example, if the main part is subjected to tensile shear under normal conditions, the test piece shall be designed as a lap shear form.
Quality control begins with acceptance of raw materials such as adhesives and catalysts. The purchase order is generally required to specify the required quality performance of the feed, which is given in the actual requirements entry or material description.
(1) Package: The first thing to check is the case of the package. The contents of the inspection should include the following items:
Damage: The physical damage to the plastic packaging box causes the sealing strip to crack and the moisture and dust will enter the box and contaminate the film. Damage to the package will also prevent a barrel of glue from being metered on the automatic measuring device.
Leakage situation - If the box is equipped with a matching adhesive, the leakage of the adhesive components will change the ratio of the catalyst to the resin and also cause the loss of the adhesive.
The situation of the sign - the people of the package should include: product name; storage period; manufacturer name; recommended storage conditions; production date; instructions for use; batch number; safety issues.
(2) Adhesives: Adhesive inspections purchased should include Class II tests. Physical tests such as fluidity, gel time, and volatilization rate are all parameters that technicians are most concerned with to ensure the quality of the bond. Adhesive fluidity is one example of this and is important in the bonding process. Adhesive fluidity can not be too large, otherwise it will cause glue layer lack of glue; fluidity can not be too small, otherwise it will make the glue layer too thick, or glue can not be completely filled with glue. Methods for determining physical properties include:
The ASTM method for measuring physical properties includes D816, D898, D899, D1084, D1337, D1448, D1489, D1490, D1579, D1582, D1583, D1584, D1875, D1916, D2183, D2556, D2979, D3121, D3236.
(3) Mechanical properties of adhesives: The mechanical properties of adhesives are of great concern because they determine the structural strength of the finished product. Test methods for the mechanical properties of adhesives include standard test methods for durability, flexibility, and fatigue.
ASTM mechanical properties test methods are ASTM D897, D903, D905, D906, D950, D1002, D1062, D1144, D1184, D1344, D1781, D1876, D2095, D2182, D2295, D2339, D2557, D2558, D2918, D2919, D3111, D3163 , D3164, D3165, D3166, D3167, D3527, D3528, D3568, D3702, D3807, D3808, D3931, D4027, E229.
(4) Other properties of adhesives (including creep): Other test methods for adhesives are: ASTM D896, D904, D1146, D1151, D1174, D1183, D1286, D1304, D1382, D1383, D1581, D1713, D1780, D1828, D1877, D1879, D2294, D2739, D3310, D3632, D3929.
2. Surface treatment control After the feed quality is determined, the second process is the surface treatment of the adherend. In order to make the adhesive quality reliable, the surface treatment must be carefully controlled.
If the surface needs chemical treatment, the heart must control the proper procedures, soak temperature, solution concentration and contamination. If blasting is used, sand should be changed regularly. Solvent wipes should have enough clean cloth, fresh solvent for cleaning, and always check if the cloth or solvent container is contaminated. The effect of the surface treatment can be verified by the water film failure test. After the final treatment of the surface treatment, the surface was coated with deionized water and the adherent surface was examined for its ability to form a continuous water film. If it is considered that the surface treatment can meet the requirements, the surface should be kept clean and dry before bonding, and the primer should be coated on the treated surface as soon as possible.
3. Adhesion process control In addition to the above-mentioned adherend surface treatment to be controlled, the bonding process including pre-mating, gluing, assembly, and curing is also controlled.
(1) Pre-coordination: All the parts to be glued should be assembled together before gluing to check if they can be in close contact. If two or more parts are not pre-fitted prior to bonding, it may be difficult to ensure good bonding joints due to poor adhesion. If it is a highly efficient and repeatable production and the assembly accuracy is guaranteed, the pre-mating process can sometimes be omitted. The fit of the initial product can be checked with an anti-ablative film that can generate a mark, which can greatly reduce the risk of poor assembly of expensive or critical components. When there is no problem with pre-mating, mark each bonded part in the pre-match so that the parts can be assembled easily after gluing. The process control test pieces, ie the remaining parts with labels in the assembly, shall be placed together with the set of pre-mated parts to be adhered and shall be examined during the pre-match inspection. These process control test pieces must go through each process as well as the finished product. After curing, test the test pieces to determine whether the adhesive and surface treatment and other process conditions of the lot meet the requirements.
(2) Gluing: Most structural adhesive films need to be primed when used, and primers are usually sprayed with air or without air. Roller or brush can be used when the area is small or no spraying equipment. The undercoat must be air-dried, and some must be dried to remove the solvent. Usually the thickness of the primer will affect the bond strength, so it should be controlled and tested, usually by checking the glue applicator regularly and measuring the thickness of the dried primer.
Before the film adhesive is applied, remove the paper or plastic protection/isolation film, and then lay the film on the adhesive surface. Be careful not to wrinkle, otherwise it will trap air. A common operation error is that the separator is not removed when the parts to be bonded are assembled, and some bonding operators use special inspection heads to ensure that the separator is torn off. In the inspection record, the type of adhesive, batch number, group number, and time and date of gluing should be included for future reference when damage occurs. Also record the end of the pot life, which is useful for controlling assembly and adhesive curing.
(3) Assembling: The glued parts are often glued together with a tool or holding device. The cleanliness and suitability of the tool should be checked. The effective time of the surface treatment, the pot life of the adhesive and the holding time of the adhesive curing are checked during assembly.
Also check that the parts to be glued are assembled in the correct order and fit. It is important to keep clean and adjust the humidity of the air. Parts and adhesives are exposed to the control from the preparation of the adhesive until the initial curing. Operational situation control usually includes the following aspects:
1, the temperature is maintained at 18-320C
2, relative humidity to maintain 20-65%;
3. The incoming air must be filtered to prevent the operating space from being contaminated;
4. Make the operating space slightly different from the surrounding environment. The above conditions can be detected with a recording temperature and humidity indicator.
(4) Curing: The curing of adhesive in any joint is a function of time-temperature-pressure. The length of curing time can be controlled by manual timing or automatic timing device. The detection is usually based on the temperature and/or pressure recorder curing chart, while recording the temperature and pressure.
The specified curing temperature always refers to the temperature of the adhesive layer. Because the adhesive has poor heat transfer, it must be added for a period of time to allow heat to be transferred to the adhesive layer. In addition, heating fixtures also take up most of the curing cycle.
The heat source must ensure the required heat and uniformity when curing, and must consider the following factors:
1, heating rate;
2, the maximum temperature;
3, temperature range or coverage when heated and cured;
4, cooling cooling characteristics.
(5) Standard test piece: It is best to make a standard test piece and go through the same process with the adhered parts. Standard test pieces should be designed for test methods that represent the requirements of the main structure for loading. For example, if the main part is subjected to tensile shear under normal conditions, the test piece shall be designed as a lap shear form.
Golf Towel,Golf Shoes ,Golf Balls ,Golf Bags
Artificial Grass Co., Ltd. , http://www.nbartificialgrass.com