JPS59178220A - Molding method of tank panel unit body - Google Patents

Abstract

PURPOSE:To manufacture a panel unit body free from scattering of glass fiber and excellent in strength by a method wherein SMC (sheet mold compound) and reinforced fiber are lapped in a mold so that the SMC makes a pressed surface and formed at high temperature and high pressure. CONSTITUTION:An SMC and a reinforced fiber are arranged in layers and formed at high temperature and high pressure so that the panel unit body obtained by molding the SMC makes a surface in contact with liquid (or a pressed surface). The working quantity of the reinforced fiber is 1-10wt% and when the quantity exceeds 10wt%, since the reinforced fiber is not impregnated fully with SMC, a sufficient strength can not be obtained and the reinforcced fiber scatters remarkably. Since a reinforced layer 2 impregnated with SMC is arranged on the back (the side not in contact with liquid) of the SMC layer 1, strength reinforcing effect is large and since reinforcing fiber applied is small in quantity, the reinforced fiber dust does not scatter.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for forming a panel unit for a prefabricated tank that is stable in strength and can be obtained under a favorable working environment.

Tank glass wi, which is generally formed using the press molding method
, M# reinforced plastic (hereinafter referred to as FRP) panel unit is made into a sheet by crushing a resin compound containing resin/filler/pigment/internal mold release agent/hardening agent with glass fibers. Sheet molding compound (
SM (hereinafter referred to as SMC) is cut into appropriate dimensions, and the cut SMC is charged into a heated mold and pressurized.
C-MMD molding method, Moshikke-L Pre-form massodized metal die in which resin compound and glass fibers such as glass cloth and continuous filament cloak are individually titrated into a mold and pressure-molded ( Below, P.M.
1) is produced by any of the following molding methods. However, although SMC molded products are superior in productivity and molding environment conditions, they have the disadvantage that their strength is weaker and more variable than PMD molded products. Also, PMD
In the case of molded products, they are strong, have little puffiness, and are stable, but because a large amount of glass fiber is handled without fully immersing the resin during molding, fine glass fiber powder is scattered, creating a poor working environment. 1'. Occupational health of workers - has the disadvantage of being unfavorable.

In order to improve this drawback, the present inventors developed XaR・1, and as a result, by using a combination of SMC and a small amount of reinforcing fiber, a structure with high strength and stability can be obtained with less scattering of fine powder of the reinforcing fiber. The inventors have discovered that a panel unit for a tank can be obtained, and have completed the present invention.

In the present invention, SMC and reinforcing fibers are placed in a mold.
The present invention provides a method for forming a panel unit for a tank, which is characterized in that the MCs are placed one on top of the other so as to serve as the liquid contact surface (pressure receiving surface), and then heated and pressure molded.

The SMC used in the present invention includes thermosetting resins such as unsaturated polyester resins, vinyl ester resins, and epoxy resins, as well as well-known curing agents, fillers, pigments, internal rigidifying agents, and low-shrinkage agents as necessary. Conventionally known SMC is made by impregnating reinforcing fibers such as glass fibers, carbon fibers, and metal fibers with a thermosetting resin compound obtained by blending other additives into a sheet shape. Among these, unsaturated polyester resin is preferred as the thermosetting resin, and chopped glass fiber is preferred as the reinforcing fiber. The proportions of the thermosetting resin and reinforcing fibers are usually in the range of 60 to 90 weight percent and 40 to 10 weight percent, preferably 65 to 75 weight percent and 35 to 25 weight percent.

The reinforcing fibers used in combination with SMC in the present invention include:
Examples include glass fibers, carbon fibers, metal fibers, etc., and their form is preferably a cloth or mat made of long fibers and/or continuous fibers, with glass cloth and continuous ass filament mat being particularly preferred.

The proportion of SMC and reinforcing fiber used is usually in the range of 90 to 99% by weight and 10 to 1% by weight, but especially 9.
When used in the range of 4 to 99 weight percent and 6 to 1 weight percent,
This is preferable because the strength can be efficiently improved with a small amount of reinforcing fibers, and there is less scattering of reinforcing machine fine powder that degrades the working environment.

If the amount of reinforcing fibers exceeds 10% by weight, the reinforcing fibers will not be sufficiently impregnated with SMC, so that little improvement in strength will be observed and the amount of reinforcing fibers will scatter, which is undesirable.

In order to obtain a panel unit for a tank by the molding method of the present invention, SMC and reinforcing fibers are placed in a mold so that the SMC constitutes the liquid contact surface (pressure receiving surface) of the panel unit obtained by molding. They may be placed in an overlapping manner and then shifted by conventionally known heating and pressure molding. Although it is usually molded with a two-layer structure of SMC/reinforced fiber,
If necessary, three-layer structure such as SMC/reinforced fiber/SMC,
Alternatively, it may be molded in a multi-layered structure. Also, S
The reinforcing fibers used in combination with the MC do not necessarily need to be uniformly applied over the entire surface of the SMC, and may be placed preferentially in areas where the strength is weak.

As for heating and pressurizing conditions, the pressure is usually 30 to 100 kf/
ant, preferably 40-'70 k)+/cJ,
The pressurizing time is usually 3 minutes or more, preferably 5 to 7 minutes, and the mold temperature is usually 11.0 to 160°C, preferably 115 to
145℃, particularly preferably the reinforcing fiber side mold is 130-1
At 45°C, the temperature of the SMC side mold is 10 to 15°C lower than that.

An example of a panel unit for a tank obtained by the molding method of the present invention will be explained with reference to the drawings. Figure 2 is an A-Δ' cross-sectional view of the box-shaped panel unit shown in the fR1 diagram, in which the reinforcing layer 2 impregnated with SMC efficiently uses a small amount of reinforcing fibers. Since it is placed on the non-wetted side, it has a large strength reinforcing effect and has little variation. Furthermore, since the amount of reinforcing fibers used is much less than that of PMD molding, there is an advantage that there is almost no concern about deterioration of the working environment due to scattering of reinforcing fiber fine powder.

The method of the present invention will be explained in more detail with reference to Examples below. In addition, all parts and percentages in the examples are based on weight.

Example 1 After placing two sheets of roving cloth (230 g/rd) of 1050 x 105 (l vsm) in the mold, 9501 x 950 fi SMC (DI made by Dainippon Ink and Chemicals Co., Ltd.) was placed on top of it. MAT 2440-T) 1
6.6 kg, mold temperature 135°C, pressure 500
(approximately 45 klr/cn) and pressurized for 6 minutes to obtain a diameter of 838 mm and a height of 75 mm as shown in Figure 1.
1000+nX1.mm arcuate convex portion. OOO
A box-shaped panel unit for an FRPil tank was obtained, which was difficult to achieve. The obtained panel unit contained about 3% of reinforcing roving cloth and had excellent strength. still,
There was almost no scattering of glass fiber fine powder during molding.

Examples 2 to 3 and Comparative Examples 1 to 2 SMC was molded under heat and pressure in the same manner as in Example 1, except that O-bing cloth and SMC were used in the proportions shown in Table 1.
A solid plate approximately 61mm thick was obtained, either alone or in a SMC/Bing cloth Nitil construction. JT from the obtained flat plate
Test pieces were prepared according to SK-69+1 and subjected to a bending test. Table 1 shows the results.

Table 1

[Brief explanation of the drawing]

Fig. 1 is a plan view of an FRP box-shaped panel unit having an arc-shaped convex portion in the center, and Fig. 2 is a cross-sectional view taken along line AA' of the box-shaped panel unit shown in Fig. 1. . 1: sMc layer, 2: Reinforcement layer made of reinforced m fiber impregnated with SMC.

Claims (1)

[Claims] Sealing molding compound (SMC) and reinforcing fibers are placed one on top of the other in a mold so that the sheet molding compound becomes the liquid contact surface (pressure receiving surface), and heat and pressure molding is performed. A method for forming a panel unit for a tank, which is characterized by: