With the development of stone conservation engineering practice, the maintenance technology is greatly enriched. Conservation theory is also emerging. Various theories are based on the analysis and answering of various problems and phenomena in the practice of conservation, which have their rationality and applicability, as well as their one-sidedness and restriction. In the recent practice of stone conservation, some new problems have emerged, and some new ideas have been formed, which are summarized as follows.

First, not all natural stone needs protection

If it is only waterproof and anti-alkali, some high-hardness, high-density stone in the ten-hanging construction can not be protected. This also applies to some coarse-grained granite. For example, in the igneous rock, the coarse-grained magmatic rock obtained by slow cooling has a large amount of quartz. This low-density quartz surface water and other pollutants are infiltrated. The theory was confirmed and recognized by Maurizio, a conservation expert at the International Stone Association of the United States. Which materials need to be protected? Which stones do not need to be tested is dripping water under the polished surface of marble or dripping vinegar on the polished surface of granite. If the residue of anhydrous or vinegar remains after 5 minutes, the marble or granite of this variety may not be Do protection. This is basically the case with the “Hua’an Jade” marble from Fujian.

Second, the stone protection should be suitable for the construction of materials, construction of materials

In the engineering practice, it will be found that the protective agent has poor protection effect on some varieties of stone. Excluding improper construction and production failure, the most likely reason is that the correct stone chemicals are not used for protection. For example, granite and marble have different formulas for their mineral composition and chemical composition. Even the same type of stone will increase or decrease the concentration of silicone resin due to differences in density and chemical composition. For example, the concentration of silicone resin in sandstone protectants will be higher, and the concentration of silicone resin in granite or marble protectants with higher hardness and density will be lower. Therefore, in the construction of stone conservation, it must be adapted to the material, and it must be constructed according to the material. Different chemicals and different construction techniques are selected for different stone materials. This further illustrates the need to establish a stone conservation database. It is like compiling a dictionary or encyclopedia of stone conservation. By checking the selection of the correct chemicals and construction methods before the maintenance and construction, and taking the medicine according to the prescription, not only the effect can be significant, but also the annual production cost can be saved.

Third, do not blindly believe in imported stone conservation products, and do not prejudice domestically produced products.

At present, the maintenance products of foreign brands are generally considered to be a symbol of high quality. However, its high price affects the promotion of foreign brands. The maintenance products of domestic brands are generally not optimistic, but they also have a certain market share because of their low prices.

In fact, these prejudices stem from the lack of understanding of stone conservation knowledge. All protective agents, whether imported or domestically produced, are composed of active ingredients plus diluents and auxiliaries. There is no difference between this entry and domestic production. In recent years, the development and application of domestic stone protectant products have developed rapidly, and it has been close to foreign advanced water in the field of silicone monomer manufacturing and resin synthesis. It is equivalent to foreign countries in the compounding process. In the field of construction applications, it is ahead of foreign countries.  

Product  Description

This valve is a kind of rubber sealing Butterfly Valve, widely used in electric, hydraulic, chemical industry, urban construction industries such as water supply and drainage pipeline system, opening and closing as control medium flow or control device.
Using body lining rubber, butterfly plate line form, can be two-way sealing, reliable sealing, long service life; Small flow resistance. The pressure loss is small, dilettante size small, easy to install.

Butterfly Valve

Butterfly Valve,Wafer Center Butterfly Valve,Concentric Butterfly Valve,Cast Iron Butterfly Valve

Hebei Lanwei Imp. & Exp. Co., Ltd. , http://www.hblanwei.com