I. There are two kinds of coating processes in China: hot curing coating and cold curing coating. The differences of the two coating processes are as follows:
1, hot vulcanization coating process is before the drum assembly, the drum skin in the lathe turning about 2-3mm deep thread groove, brush two layers of adhesive (iron adhesive, rubber adhesive), and then the rubber plate pressed on the drum skin, into the vulcanization steam furnace heating 180℃ vulcanization, vulcanization after the completion of the lathe turning coating pattern. Then can be assembled shaft, fixed sleeve, bearing housing, etc.
2. Cold vulcanization coating process requires the surface of the drum to be flat. The drum skin shall be derusted by Angle mill, and the rolled sheet shall be directly bonded to the surface of the drum after being coated with special adhesive produced by the glue board manufacturer.
3. Disadvantages and limitations of hot curing adhesive:
Under the condition of hot vulcanization process of rubber bag because of the low sulfide pressure (6-8 kg/m), high sulfur content and wear-resisting performance is poor, use easy ageing, use hot pack glue roller hardness that is soon SHOREA 82 (silicone) hardness, low adhesion of conveyor belt, and clean function is poor, the second thermal plastic bags need to increase the thread turning drum skin and into the process of vulcanization vulcanizing boiler furnace, increasing the corresponding equipment and processing technology, at the same time also have certain influence to the environmental pollution, it is recommended that the in-situ cold vulcanization package glue tube bag glue process.
Ii. Compared with the traditional process, cold curing adhesive has the following advantages:
1. Cold curing adhesive bonding with metal roller 12 n/mm; Pressure of 50 kg/cm2 during vulcanization; High rubber compactness, good wear resistance; The service life is several times of the traditional process, the friction coefficient is high, reduce the belt stress; Rubber has good elasticity and good adhesion resistance.
2. Traditional glue coating process and metal roller adhesion 3-10 n/mm; Pressure 6-8 kg/cm2 during vulcanization; Low compactness and poor wear resistance of rubber; Low service life; The adhesive force with the tape is small, which aggravates the tensile stress of the tape. Fast aging, resulting in rubber, resulting in material adhesion.
3. Suitable for on-site production, less floor space and equipment, effectively reducing the production input in the process of processing and production.
Three, according to. The company is now in possession of the information that... And all. The drum repair plastic wrap mainly adopts the products of German Tiputopu Company. The cold-coated plastic process adopted by German Tiputopu company is superior in processing technology, production cost and product quality.
1. Roller coating material
Uni-60 (REMA LINE 60 Economy)
It has the characteristics of strong wear resistance and impact resistance.
Typical applications:
For non-drive wheel coating, no grooving;
Used for all kinds of anti-wear rubber gaskets.
2. Roller coating material with high wear resistance
RemaGrip 70
Isoprene, polybutadiene rubber, styrene butadiene rubber composite material;
Excellent high coefficient of friction and wear resistance
Typical applications:
Rubber coating for driving and driven wheels (50MM large rhomboid grooves are especially suitable for steel cable conveyor belt and high-speed, high-tension conveyor belt)
3. Roller coating material
RemaGrip CN - 70 / SL
Excellent high coefficient of friction and wear resistance;
Four standard thicknesses :10,12,15,20 mm;
2000 X 10,000 mm;
Typical applications:
For all kinds of driving wheel coating (50MM large rhomboid grooves are particularly suitable for steel cable conveyor belt and high-speed, high-tension conveyor belt drum material).
4. Roller coated ceramic material
RemaGrip CK - X
Isoprene, polybutadiene rubber, styrene butadiene rubber composite material;
With small ceramic blocks; Excellent high friction coefficient and wear resistance;
Typical applications;
Suitable for high wear, easy to slip under extreme conditions of the driving wheel coating is particularly suitable for steel cable conveyor belt and high speed, high tension conveyor belt.
5. Selection of drum coating thickness
Drum diameter coating thickness
Diameter: < 320 mm Thickness: 8 mm
Diameter: 320-800mm Thickness: 8-10mm
Diameter: > 800mm thickness: 10-15mm
Iv. Description of the production process of cold cladding adhesive on site
1. Surface treatment:
(1) Due to a lot of dirt, dust, grease, water, rust and other organic or inorganic pollutants on the surface of the metal, affecting the wet adhesive. Therefore, in order to improve the bonding strength, the mechanical, physical, chemical and other methods are used to clean, rough, activate the surface of the adhesive, change the surface properties, in order to facilitate the adhesive good infiltration, firm bonding, and can improve the durability and service life of the joint. After surface treatment, the metal surface can be changed into a bonded surface with high surface energy, high activity and high effective area.
(2) Common surface treatment methods include degreasing treatment, mechanical treatment and chemical treatment. The following aspects should be considered when selecting surface treatment methods:
Types of drum surface and fabrics;
(2) The types of pollutants, such as animal oil, vegetable oil, mineral oil, lubricating oil, dust, moisture, rust and the degree of pollution;
(3) Physical characteristics of the pollutant, such as the degree of pollution, tightness or tightness;
Working environment and conditions.
(3) Mechanical grinding and sandblasting are used to remove the organic or inorganic substances that are not conducive to adhesive bonding, provide the surface with appropriate roughness, increase the effective bonding area, improve the adhesive's wetting to the surface of the adhesive, and improve the adhesion performance.
(4) Generally, the surface treatment of the metal surface roller can be done with a steel wire brush, a grinder or sandpaper brush to remove the loose oxide layer on the surface, or with a chemical treatment method. If the roller or the bonding surface of the fabric is rubber, it can be brushed with a portable grinder or steel wire brush. If the bonding surface of the fabric is fabric, the wool should be made by a portable electric wire machine.
(5) Cleaning agents (such as acetone, anhydrous ethanol, trichloroethylene) shall be used to remove surface dirt after the brushing treatment. After cleaning, there must be a necessary time for drying, otherwise the residual solvent on the adhesive surface will affect the bonding strength.
(6) Then apply a layer of PR-200 metal primer evenly and quickly on the processed surface with a brush to prevent re-contamination and prolong the storage life of the treated metal. In addition, it is also beneficial to the wetting of the adhesive on the surface and improve its bonding strength and durability. Let stand for 60 minutes to dry thoroughly.
2. Mixed glue solution:
(1) Pour ur-R20 curing agent in the bottle into the iron bucket containing SC2000 adhesive, fully mix and stir it evenly.
(2) According to the actual needs, part of each glue and curing agent can be mixed in other containers according to the ratio of weight to 100:4.
(3) The dispensing glue solution must be ready to use immediately, and it should be used up within 2 hours of application period, that is, from mixing to using up should be controlled within 2 hours. Don't let it go for long.
3. Gluing:
(1) Use a short hard brush to evenly coat the PR200 coated and fully dried metal surface in one direction. The glue layer should be uniform and not too thick. And make it completely dry until it does not adhere to the back of the finger and there is a feeling of adhesion, then brush the next glue. (not less than 30 minutes)
(2) After the first pass is completely dry, the second pass is applied on the metal surface SC2000 adhesive, and the first pass is applied on the CN adhesive board.
(3) Because the surface of the adhesive is easy to adsorb air, in order to prevent the formation of air bubbles or pores in the adhesive layer, the coating should move in one direction. Glue speed should not be too fast, in order to facilitate the discharge of air. The number of times of glue is generally 2 times of metal, CN rubber for a time, must be completely dry in the first glue before the next glue, not too hasty.
4. Drying: The solvent-based adhesive is dried after being coated. The main purpose of drying is to volatilize the solvent, increase the viscosity and promote the chemical crystallization reaction. The drying time should not be too long or too short. After each gluing, the glue should be dried until the hands are not sticky. The environment of drying should be well ventilated, clean, clean and dry.
(1) This product is a chemical product and should be operated away from the fire source.
(2) In the low temperature, wet environment bonding, can take baking and drying methods and measures.
5. Adhesion:
(1) After the second gluing, when it sticks to the back of the fingers, the rubber plate should be aligned and affixed to the metal surface of the conveyor driving drum, and the compressed roller should be used to compress and exhaust gas. Finally, the rubber plate should be carefully pounded from the middle to the back for 2 ~ 3 times.
(2) To be aligned with the position, do not stagger back and forth, adhesive after appropriate pressure (hammer pressure or roll pressure), to move out of the air, dense rubber layer. After bonding to extrude a small ring, it is not lack of glue, if found gap or lack of glue should be filled.
6. Solidification: This process is the key to obtain good adhesion performance. The strength can be maximized only after complete solidification. In order to obtain good strength, the curing process is carried out under appropriate conditions, including temperature, time and pressure.
(1) The site can be cleaned after 2 hours at normal temperature. After 24 hours of static curing, the production can be operated under load.
(2) If conditions permit, prolonged curing time will make the bonding effect better.
(3) In low temperature or humid environment, the curing time must be extended to a long enough time except for baking.
7. Sealing: In order to obtain the best bonding effect, the interface joints between wear-resistant rubber lining plates are sealed with rubber repair agent.
V. Matters needing Attention
1. During operation, the power should be cut off to avoid accidents caused by mechanical rotation. If the drum needs to be changed, the wheel of the reduction gear can be manually turned.
2, the product contains organic solvent, low toxicity, flammable, use the workplace to pay attention to fire, should keep a good ventilation environment, avoid inhalation of solvent poisoning. Remember that there is no open fire, baking should be kept at a distance of more than 50cm.
3. Metal primer is sensitive to water and should be carefully preserved.
4. In order to improve the bonding performance, the bonding temperature and pressure can be increased. In low temperature or wet environment, must bake the film, and should extend the time of static curing, the longer the time, the higher the bonding strength.
5. Glue solution should not be in contact with water, and the bonded belt must be kept fully dry, otherwise the curing degree and bonding strength will be affected. Do not use this adhesive in an environment with temperature less than 10℃ or humidity greater than 90%.