JPH033565B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for constructing a concrete mixing device to resist wear. More specifically, the present invention relates to a method for constructing abrasion-resistant parts of concrete mixing equipment that are particularly susceptible to abrasion damage due to contact with fresh concrete.

The walls of concrete mixing equipment suffer significant abrasion and damage due to contact with fresh concrete, and improvement of this problem is strongly desired. In particular, the concrete mixing equipment installed on concrete mixer trucks has a high operating rate, and
Because the amount of fresh concrete loaded and transported per cycle is usually about 10 tons, the parts that come into contact with the fresh concrete, for example,
The durability of the hoppers, drums, chute walls, and blades has been severely damaged by wear and tear, and their durability has been a major problem in the industry. In particular, the wear and tear of the hopper and chute due to contact with fresh concrete is significant, and improvements in this respect are strongly desired.

In addition, fresh concrete adhering to the walls of the concrete mixing device must be thoroughly cleaned and removed before it solidifies, resulting in problems such as rusting in addition to a decrease in work efficiency.

In order to avoid these problems, for example, a method of attaching a rubber sheet to the wall surface of a concrete mixing device with bolts or the like has been used. However, although this method improves wear resistance, fresh concrete tends to adhere to the bolt head, and problems such as cleaning and removal of this and the resulting rusting have not yet been solved. There was also the problem that the rubber sheet was easily damaged when cleaning and removing concrete.

As a result of intensive research into ways to solve these problems, the inventors of the present invention found that by forming a two-component urethane resin coating layer on the parts of the concrete mixing device that are prone to wear and damage due to contact with fresh concrete. have found that the various problems mentioned above can be solved, and have also found that by forming a resin layer using an open-cell flexible urethane foam sheet, various problems can be solved and painting workability can be significantly improved. Heading: The present invention has been completed.

That is, the present invention applies a primer to the wall surface of a concrete mixing device, then adheres and adheres an open-cell softened urethane foam sheet onto the primer-coated surface, and then applies a two-component urethane resin coating material to the urethane foam sheet. Provided is a wear-resistant construction method for a concrete mixing device, characterized in that the urethane foam sheet layer is further coated with a two-component urethane resin coating material of the same type or different from the urethane resin coating material described above. It is something.

The method of the present invention is particularly advantageously applied to concrete mixing equipment installed and mounted on a concrete mixer truck, which usually consists of a hopper, drum, blade, and chute. Adhesion of concrete is significantly improved, and even if the fresh concrete adheres, it can be easily peeled off, so the decrease in workability due to washing and removal is improved and problems such as rusting are avoided.

The construction method of the present invention will be explained in detail below.

The primer used in the present invention is not particularly limited, and may be any known one-component or two-component primer, but is preferably a two-component primer that has good adhesion to the wall surface of the concrete mixing device. It is preferable to use one that has excellent interlayer adhesion with the urethane resin coating material. Examples include a two-part epoxy resin primer, a one-part moisture-curable urethane resin primer, a modified silicone primer, and a phenoxy resin primer. The amount of these primers to be applied is not particularly limited, but is usually about 30
500g/m ² .

In the method of the present invention, various known open-cell flexible urethane foam sheets can be used;
Generally, an apparent specific gravity of 0.8 or less is suitable. It is also preferable that these urethane foam sheets are not contaminated with substances that inhibit impregnation with the two-component urethane resin coating material, such as silicone mold release agents and machine oil. The thickness of these urethane foam sheets can be appropriately determined depending on the desired thickness of the two-component urethane resin coating, but is usually about 0.5 mm or more.

The two-component urethane resin coating material used in the method of the present invention is not particularly limited, and various commercially available coating materials can be used. For example, tolylene diisocyanates as the main ingredient,
Contains phenylene diisocyanates, naphthalene diisocyanates, dimers or trimers thereof, or polyisocyanate compounds obtained by reacting these with polyhydric alcohols, polyether polyols, polyester polyols, etc., On the other hand, a curing agent containing a polyamine compound or a polyol compound is used as the curing agent component. In use, the main component and curing agent component are mixed, and the viscosity at this time is preferably 1 to 1000 poise at 20° C. in consideration of impregnation into the urethane foam sheet and ease of application. Commercially available two-component urethane resin coating materials include Sumikadyne F310 (manufactured by Sumitomo Chemical Co., Ltd., viscosity when mixed is 60 ps), Cosmoflex F40 (manufactured by Sumitomo Chemical Co., Ltd., viscosity when mixed
50 ps) Art Floor (manufactured by Chugai Shoko Co., Ltd., viscosity when mixed is 70 ps), and these are used advantageously.

To carry out the method of the present invention, first, a primer is applied to the area to be constructed using a known application method such as troweling, brushing, or roller brushing. Next, an open-cell flexible urethane foam sheet is attached to the primer-coated surface. In this case, it is preferable to adhesively adhere the urethane foam sheet while the primer is uncured, but the urethane foam sheet may be adhesively applied using a normal adhesive after the primer has hardened.

After the urethane foam sheet is fully adhered,
The urethane foam sheet is sufficiently impregnated with the two-component urethane resin coating material by a known method such as brush coating, roller brush coating, trowel coating, or spray coating. In this case, it is not preferable to perform the impregnation operation with insufficient adhesion of the urethane foam sheet, since this tends to create an air layer between the primer layer and the urethane foam sheet layer. In addition, if the impregnation is insufficient after one impregnation operation, after the first impregnated coating material has hardened,
The same impregnation operation can be performed again to complete the impregnation.

The same or different type of material as above is coated on the urethane foam sheet layer formed by sufficiently impregnating and curing the coating material until the edges and joints of the urethane foam sheet form a smooth surface. Apply multiple coats of two-component urethane resin coating material.
It is important that the two-component urethane resin coating material used for overcoating be integrated with the coating material impregnated into the urethane foam sheet and cured, and as long as it is integrated, different two-component urethane resin coating materials It is preferable to use Recoating can be carried out by the above-mentioned known methods such as brush coating.

The thickness of the two-component urethane resin layer containing the urethane foam sheet formed in this manner is preferably about 1 mm or more, and if it is less than that, it becomes difficult to achieve the object of the present invention.

Further, one example of a specific embodiment of construction according to the present invention will be explained based on the accompanying drawings.

According to the construction method of the present invention, first, a primer layer 2 is formed by applying a primer to the wall 1 (usually a steel plate) of the part of the concrete mixing device that comes into contact with fresh concrete. Next, primer layer 2
After adhering an open-cell urethane foam sheet 3 thereon, the urethane foam sheet 3 is impregnated with a two-component urethane resin coating material to form a urethane foam sheet layer 4'. Thereafter, a two-component urethane resin coating material of the same type or different type as described above is coated over the urethane foam sheet layer 4' until the seams 5 and edges 6 of the urethane foam sheet become smooth. ' to form a two-component urethane resin coating material layer 4 to complete the wear-resistant construction.

According to the method of the present invention, the abrasion resistance of the parts of the concrete mixing device that are easily damaged by abrasion due to contact with fresh concrete is improved, the adhesion of fresh concrete is prevented, and even if it does adhere, it can be easily removed. Furthermore, it is sufficient to repair damaged areas due to long-term use by simply applying a two-component urethane resin coating material to the area.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example: Primer 310 (Sumitomo Chemical Co., Ltd. product, epoxy resin primer) was applied to the inner surface of the hopper of a concrete mixer truck with a length of 7.7 m, a width of 2.5 m, and a height of 3.5 m.
Apply with a brush at a rate of 200gr/m ² and directly apply the apparent specific gravity.
Open-cell soft urethane foam with a thickness of 0.1 mm was pasted. Then, after 2 hours, Sumikadyne
F310 (Sumitomo Chemical Co., Ltd. product, two-component urethane resin paint, viscosity when mixed with main agent and hardener: 60 poise/20°C)
was impregnated at a rate of 1800gr/ ^m2 .

After 2 hours, it was again impregnated with Sumikadyne F310 at a rate of 800 gr/m ² . Furthermore, after 2 hours, Cosmoflex F30 (manufactured by Sumitomo Chemical Co., Ltd., two-component urethane resin coating material, base agent and curing agent mixture ratio of 1/1) was applied.
(weight), viscosity when mixed 50 poise/20℃) 600gr/
It was applied at a rate of m ² . After 16 hours, Cosmoflex F30 was applied again at a rate of 600 gr/m ² to obtain an integrated two-component urethane resin coating material layer with an average thickness of 3 mm.

In this way, when a concrete mixer truck with abrasion-resistant construction applied to the hopper was loaded with about 10 tons of ready-mixed concrete at a time and operated, even after 200 operations (about 3 months), there was still no fresh concrete in the hopper. No damage due to adhesion or abrasion was observed.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of construction by the construction method of the present invention. Each symbol in the figure represents the following meaning. 1... Container wall of the part of the concrete mixing device that comes into contact with fresh concrete, 2... Primer layer, 3...
Open-cell urethane foam sheet, 4...Two-component urethane resin coating material layer, 4'... Urethane foam sheet layer, 5... Seam of open-cell urethane foam sheet, 6... End of open-cell urethane foam .

Claims (1)

[Claims] 1. After applying a primer to the wall of the concrete mixing device, and then adhesively pasting an open-cell flexible urethane foam sheet on the primer-applied surface,
The urethane foam sheet is impregnated with a two-component urethane resin coating material, and the urethane foam sheet layer is further coated with a two-component urethane resin coating material of the same type or different from the urethane resin coating material. Wear-resistant construction method for concrete mixing equipment.