JPS5977194A - Coating treating conduit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to coated metal conduits. More specifically, the present invention relates to a coated conduit which imparts desired surface properties to the base conduit by coating the inner surface or the inner and outer surfaces of the base conduit for conducting sewage, wastewater or seawater with a coating layer.

An important surface property is generally corrosion resistance.

In the conventionally known coating layer, which is coated with anticorrosion paint or bituminous paint or lined with rubber or plastic, the material of the conduit to be coated, that is, the base conduit, must be carefully treated as a pretreatment before coating. Need to adjust.

If there is dirt, rust, laitance, etc. on the base material, coating or coating such as lining must be repeated, and adjustment requires considerable time and effort, resulting in high labor costs.

Furthermore, if the coating layer is blistered or otherwise deteriorated due to slight carelessness, defects such as cracks and peeling may occur, resulting in a lack of uniformity in work.

Since it is generally technically difficult to apply a thick coating with a thick coating, the coating layer is worn away by friction from sewage, drainage water and seawater, and eventually the base conduit is exposed in places. In this way, the anticorrosion effect gradually disappears.

Particularly in areas where corrosion is severe due to these fluids, use coal tar epoxy paint, which is said to be corrosion resistant1.
For example, buried pipes may lose their corrosion protection after only 4.5 years. Even coatings with linings may lose their anti-corrosion properties due to the action of fluids, and depending on the nature of the fluids, scratching may occur on the surface of conduits with plastic lining on the inside.

Conduits with a cement mortar coating are also known, which, although relatively resistant to wear,
5. Because it is thick like a pipe, the weight of the pipe increases significantly, making handling and transportation inconvenient. 0. Also, cracks are likely to occur on the surface due to careless curing during the formation of the coating layer, resulting in high management costs. Become. Furthermore, the cement mortar coating layer has no resistance to impact and can cause cracks and peeling when a metal conduit is bent. Furthermore, the cement mortar coating layer has no corrosion resistance against acids, and the corrosion resistance decreases due to the loss of free alkali and the like.

Polymer concrete colored layers that have recently been used undergo thermal expansion and are easily deformed during swelling, and furthermore, because the rate of heat diffusion is low, they are easily distorted by sudden changes in temperature.

Thus, conventional coated conduits have a number of drawbacks.

Therefore, the main purpose of the present invention is to eliminate such drawbacks of the prior art, and to provide a coating with so-called heavy corrosion resistance that is resistant to sewage, waste water and seawater, and also to chemicals such as sulfuric acid that may be contained in these. Another purpose is to provide a processing conduit.

To achieve this objective, the wt treatment conduit according to the present invention is applied to the inner surface KV: or both the inner and outer surfaces of the base conduit, such as steel pipes, cast iron pipes, ceramic pipes, clay pipes, and humid pipes, which conduct sewage, wastewater, and seawater. , inorganic organic cement (i.e., cement made by blending a small amount of a plastic polymer substance, for example, 5% or less, with an inorganic cement such as Citrant 9 cement, polymer cement mortar) or organic cement (i.e., 1 plasticity 43 material) A first covering material consisting of cement, single or composite plastic mortar, resin mortar, which mainly binds polymeric substances is coated as a lower coating layer, and on top of that, synthetic polymeric materials, cool epoxy paint,
F! is a coating material included in the material group consisting of tar urethane paints, bituminous materials, and coal tar materials. 2 coating material is applied as the top layer. The lower coating layer has a thickness between 0.3 and 5.0 mm, and the upper coating layer has a thickness of 0.001 mm.
It has a thickness between 1.0 mm and 1.0 mm. In some cases, the overcoating layer may be of several different types (usually two types).
Second υ material fr: Consists of a multiple structure (usually a double structure) coated with Ir.

The lower coating layer according to the present invention as described above is made of inorganic organic cement or organic cement, so it has strong adhesion to the base conduit material and has a large plugging strength. Since the base conduit blank is not directly coated or directly lined with rubber or plastic, precise conditioning of the base conduit blank is not required. This coating underlayer prevents rust-generating reactions, especially in steel pipes, cast iron pipes, etc., and is resistant to wear and tear, acid, and alkali, and prevents dissolution of clay pipes by acids and other sources. According to Vζ, if the thickness of the lower coating layer is less than 0.3W, its effect and synergistic effect with the upper layer will be insufficient. It is not necessary for the thickness to exceed 5.0 mm. If the thickness exceeds 5.0 mm, the amount of M will be excessive, making the weight of the conduit excessive and making it inconvenient to handle and transport.

Furthermore, even if moisture adheres to the base material, it does not cause any interference and is useful for hardening the substrate.

The upper coating layer according to the present invention has good adhesion to the lower coating layer, and lacks anti-corrosion properties when formed like a conventional cement mortar layer. This upper coating layer acts both by itself and in synergy with the lower coating layer to prevent impact and also supports the acid and alkali resistant effects of the lower coating layer. It has been found that if the thickness of the undercoating layer is less than 0.001 mm, its action and synergistic effect with the under layer will be insufficient, and if the thickness exceeds 1.0 mm, the material will fail. It's a waste and economically unsatisfactory.

As described above, the lower coating layer and the upper coating layer do not cause defects such as cracks or peeling, and there is no gradual loss of corrosion resistance, and there is no risk of distortion due to temperature changes, and the weight of the conduit is substantially reduced. It has been found that benefits such as non-increasing occur as a result of synergism.

An embodiment of the coating conduit of the present invention will now be described with reference to the drawings, which has a base conduit 10f, generally having a circular cross-section, as shown in FIG. The base conduit 10 is used to conduct sewage, wastewater, or seawater from steel pipes, cast iron pipes, ceramic pipes, clay pipes, humid pipes, etc.

In terms of shape, the base conduit 10 has the following shapes: Kfa) straight pipe 10a, (b) pend 10, as illustrated in FIG.
b, (c) U-shaped pipe 10c1) branch pipe 10d, etc., and the end 11 thereof is generally formed with a connecting means (not shown) such as an enlarged portion, a flantz, a screw, or the like. The inner surface 12 of the base conduit 10 is provided with an inner coating 13 and, optionally, the outer surface 14 is provided with an outer surface coloring 15.

The inner or outer surface covering ff 115, 15 includes an undercoating layer 16 of a first coating material of the type described above that covers the inner surface 12 or the outer surface 14 of the base conduit 10, as shown partially enlarged in FIG. , and a covering layer 17 comprising a second covering material of the kind described above. The thicknesses of the lower coating layer 16 and the upper coating layer 17 are as described above.

For example, the inner surface 12 and outer surface 14 of the base conduit 10 made of steel are coated with an inorganic organic cement, i.e., polymer cement mortar, N16 to a thickness of between 0.3 Ttar and 5 mm, for example between I+O+ and 3 mm. , and on top of this, an upper coating layer 17 made of bituminous material, tar epoxy paint, or synthetic polymer material is applied from 0.001 to 1.0
- for example, at a thickness between 0.001 fl and 0.3 fl. In some cases, the upper coating layer 17 has a multilayer structure consisting of different second coating materials, in the example of FIG. It has a double structure consisting of an upper portion 17b of synthetic polymer material covering this.

Next, an example of the phase coating will be described. The unframed 1-containing cement used as the first coating material forming the coating 'F layer 16 is a mixture of inorganic cement and a plastic bacterial molecular substance. The following molecular substances are mainly used:

(1) Rubber latex, styrene butadiene latex (2) Thermoplastic resin emulsion, such as polyacrylic acid ester resin emulsion (3) Thermosetting resin emulsion, such as epoxy resin emulsion (4) Bituminous emulsions such as asphalt emulsions (5)
Rubber-based and resin-based mixed dispersion (6) Water-soluble resin For example, polyacrylic acid amide An example of the composition of such an inorganic-organic cement is as follows (shown in weight ratio)
.

(Example 1) (Example 2) Organic cement can also be used as the first coating material forming the lower layer 16. This is a cement whose main binder is a plastic organic polymeric substance, and is generally made by mixing inorganic aggregates such as gravel or sand with liquid resin and fine powder such as carbonate as an extender for the resin. It is made by polymerizing resin using a curing catalyst. The resin used for this is No. Thermoplastic resins such as polyvinyl chloride, polyethylene, and acrylic resins, as well as polyester resins, furan resins, phenolic resins,
There are thermosetting resins such as polyurethane resins. An example of the composition of such an organic cement is as follows (weight ratio).

(Example 1) (Example 2) 3 gravel 26 3 sand 36 ((silica sand 8 Materials included in the group of materials such as tar epoxy/based paints, tar urethane based paints, bituminous materials, and coal tar based materials are used, and their compositions are, for example, as follows (weight ratio):

(How many mouths) Tar epoxy/based paint (Tar Pitch 40 (Shio 11)
2) Cool Evoquin paint (Example 3) Synthetic polymer material (urethane resin type) (Example 4) Synthetic polymer material (4-drug-free type) To form the coating lower layer 16, the first coating material is used to coat the base conduit 10. When coating the inner surface 12 or the outer surface 14, the constituent components thereof may be, for example,
The mixture is kneaded uniformly by stirring with a domiciliary device, and then applied to the inner or outer surface of the base conduit using an air spray gun within a wandering time of about 2 hours to a depth of between 0.3 m and 5.0 m. Cover with a thick layer and let dry. At this time, remove dust, floating rust, oil, etc. from the surface of the base conduit. If there is an old paint film, polish the surface to some extent. The above thickness is the thickness after drying. For example, in order to obtain a thickness of 3 mm after drying, it is approximately 6.5 kg in a moisture-containing state.
It may be coated at a rate of g/m2. The thus formed lower layer 16 to be shrunk is completely dried and hardened by being left at room temperature for 75 hours or more, for example.

Prior to use, the constituent components of the second covering material forming the upper covering layer 17 were sufficiently stirred and mixed, and within 5 hours thereafter, the lower covering layer 16 consisting of the first covering material was completely dried and cured. It is then applied directly onto the surface, for example with a suitable spray gun, to a thickness of between 0.001 and 1.0 mm.

After that, it is usually completely cured in 2 hours at 2°C, but it is preferable to let it sit for at least 7 days and confirm the cure before using the finished treated conduit.

A coating lower layer 16 (thickness between 0.3 and 5.0 thick) formed of various first coating materials whose compositions are exemplified and a coating formed from various second covering materials whose compositions are also exemplified. Upper layer 17 (thickness 0.001 fin to 1.0 +
The general properties and test results for A) and the composite coating made by laminating these were as follows.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of a cross section of a coated conduit according to the present invention, FIG. 2 is a diagram schematically showing various shapes of the coated conduit shown in FIG. 1, and FIGS. FIG. 3 is an illustrative view showing each side of the coated shape of the coated conduit. In the drawings, 10 is the base conduit, 12 is the inner surface, and 13
is its covering, 14 is its outer surface, 15 is its covering,
Reference numeral 16 indicates a lower coating layer, and 17 indicates an upper coating layer. Figure 1 Figure 4 Figure 2 <d)

Claims (1)

[Claims] ■- On the inner surface of the base conduit that guides sewage, wastewater and seawater,
A first coating material made of inorganic organic cement or organic cement is coated as a coating lower layer to a thickness between 0.3 and 5.0 mm, and a coating lower layer, a shite synthetic polymer material, and a tar epoxy/based paint are applied thereon. , a coating treatment in which a second coating material, which is a material included in the material group consisting of tar urethane paint, bituminous material, and coal tar material, is coated with a thickness between 0.001 mm and 1.0 mm. conduit. 2. Similarly to the inner surface, the outer surface of the base conduit is coated with the first coating material from Q, 3m+n to 5. The second coating material was coated with a thickness between 0.001mm and 1.OwIR.
A coated conduit according to claim 1 coated with a thickness between. 8. The coating treatment conduit 0 according to claim 1 or 2, wherein the coating upper layer has a multilayer structure in which different fine electrodes are sequentially coated with the present second dressing material.