JPS6157516B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a rust prevention method for piping that penetrates the oil barrier part of an oil tank, and its features include a clay-like rust prevention material with good moldability. The purpose of this product is to prevent corrosion of oil dike penetrating piping for many years by using it in combination with an elastic filler that is oil-resistant, heat-resistant, and weather-resistant.

Currently, the piping section that penetrates the concrete oil barrier has a space or gap 3 of 2 to 5 cm between the steel pipe 1 and the concrete oil barrier 2, as shown in Figure 1.
There is. This gap 3 is provided to prevent the pipe 1 from coming into contact with the concrete oil dike 2 and breaking it during vibrations caused by earthquakes, etc. However, as it is, it is not useful for damming up oil leaking from the tank, so as shown in Figure 2. As shown in the figure, this space 3 is filled with a cushioning material 4 such as asbestos or polyurethane, and the exit is blocked using asphalt 5 or a donut-shaped iron plate 6 for the purpose of waterproofing and oil-proofing. however,
In this method, the buffer material 4 absorbs moisture condensing on the concrete, which not only corrodes the iron pipe 1, but also
Rainwater enters through cracks caused by deterioration of the asphalt and gaps between the steel plate and the concrete wall, and the cushioning material always contains water, so piping in these areas is generally more prone to rust than exposed pipes. For this reason, oil leakage accidents due to corrosion frequently occur.

The present inventor has developed an extremely effective method for preventing pipes from rusting over a long period of time by combining a moldable clay material with excellent rust prevention performance and a buffering effect with an elastic filler that is oil resistant, heat resistant, and weather resistant. The present invention was achieved by discovering an advantageous method.

That is, the present invention provides a clay-like rust-preventing material made by impregnating cotton-like or powder-like fiber materials such as asbestos, glass fiber, and polyolefin nonwoven fabric with a rust-preventing oil containing petrolatum as a main component. The present invention relates to a rust prevention method for piping penetrating through an oil dike, which is characterized by filling the space between the piping and the dike and further sealing the outlet of the space with an elastic filler.

The clay-like rust preventive material used in the present invention is made by impregnating and kneading cotton-like or powdery fibers such as asbestos, glass fiber, and polyolefin nonwoven fabric with a rust preventive oil containing petrolatum as a main component. , which does not lose its anti-rust performance and elasticity over a long period of time. 10 to 200 parts of anti-rust oil is used per 10 parts of the fiber material. Rust preventive oil is generally liquid, but there are also grease-like oils. As the rust-preventing oil used in the clay-like material of the present invention, a grease-like oil is preferable, and a liquid-like oil is not preferable because it oozes out of the material and penetrates into the concrete, reducing the rust-preventing effect.
Many of the objects to be protected against corrosion according to the present invention have many existing pipes that are already quite rusted, and it is impossible to completely prevent rust in narrow spaces. Preferably, a grease-like rust preventive material containing petrolatum as a main component and containing an additive that inhibits the progression of corrosion is used. For example, it is preferable to mix petrolatum (petrolatum) with 1 to 20 parts of a sulfonate such as barium sulfonate or calcium sulfonate, or an additive that is reactive with rust such as oxidized paraffin per 100 parts of petrolatum. Petrolatum is optimal for the purpose of the present invention because it has good impregnating properties with materials and does not seep into concrete.

However, the melting point of petrolatum is around 55°C, and the temperature in piping for crude oil and heavy oil can reach around 60° to 80°C. It is desirable to add 1 to 10 parts of metal soap to 100 parts of petrolatum, and by adding this metal soap, the melting point can be raised to 90°C or higher.

Furthermore, as the elastic filler used in the present invention, elastic sealants such as butyl rubber, polysulfide, silicone rubber, and epoxy sealants can also be used, but in consideration of weather resistance, oil resistance, heat resistance, etc. A silicone rubber-based elastic sealant is preferred. Oil resistance is especially important, and if the tank is damaged and oil leaks, if the sealant that comes into contact with it is not oil resistant, the oil that passes through it will dissolve the clay inside, causing the oil to leak outside. will flow out.

Examples of the rust prevention method for oil barrier penetrating piping of the present invention are listed below.

Example 1 A Clay-like material Asbestos fiber 10 parts (weight, same below) Petrolatum 75 parts Barium sulfonate 10 parts Aluminum stearate 5 parts Petrolatum and additives were put in a kneader.
The mixture was heated and mixed at 95-110°C, and asbestos fibers were added thereto and thoroughly kneaded to form a uniform clay-like material with a melting point of about 87°C.

B Sealing material silicone rubber sealight (BM-30 manufactured by Nippon Gosei Kagaku Co., Ltd.) Example 2 A Clay-like material Polypropylene nonwoven fabric cut pieces 5 parts Petrolatum 82 parts Calcium sulfonate 5 parts Calcium stearate 3 parts Paraffin oxide 5 parts A clay-like material was prepared in the same manner as in Example 1.

B Sealing material Silicone rubber sealight (BM-30) Example 3 A Clay-like material Glass fiber cotton 10 parts Petrolatum 73 parts Barium sulfonate 5 parts Calcium sulfonate 5 parts Aluminum stearate 7 parts A clay-like material was prepared in the same manner as in Example 1.

B Sealing material Polysulfide sealant (manufactured by ABC Shokai, trade name Thiocoke) Using the clay-like material and sealant of the above example, a rust prevention comparison test was conducted with a conventional combination of asbestos and asphalt. Summer. That is, as shown in Fig. 3, the iron pipe 1 is passed through the hole above the concrete block 2 so that the space 3 is about 2 cm, and the clay-like material 7 is first pushed into the hole.
Leave a space of about 1 cm in depth near the exit and fill it with silicone rubber sealant 8 last. Similarly, an iron pipe 1' is passed through the lower hole, filled with asbestos 4, and the exit area is sealed with heated and melted blown asphalt 5. The test pieces were tested for 6 months using three methods: buried in the ground, immersed in water, and exposed outdoors. As a result, the pieces sealed with blown asphalt using the conventional method were found to have cracks in their surfaces, through which rainwater entered. The asbestos inside was crumbling and the iron pipe was severely rusted, but the method of the present invention, which was constructed using a combination of clay-like material and silicone rubber sealant, had no cracks on the surface and no rainwater could enter through the concrete. Despite this, the iron pipes did not rust at all.

[Brief explanation of the drawing]

1 to 3 are cross-sectional views of oil barrier piping for explaining the rust prevention method for oil barrier piping of the present invention. 1... Iron piping, 2... Concrete oil embankment, 7
...clay-like material, 8...elastic sealing material.

Claims (1)

[Claims] 1. A clay-like rust preventive material made by impregnating cotton-like or powder-like fiber materials such as asbestos, glass fiber, or polyolefin nonwoven fabric with a rust preventive oil containing petrolatum as a main component to form a clay-like material is used as a clay-like rust preventive material for oil dike penetrating piping. A rust prevention method for piping penetrating through an oil barrier, characterized by filling the space in the oil barrier and further sealing the outlet of the space with an elastic filler.