Di Hai Machinery entered the field of external wall thermal insulation mortar in 2005. It has been more than 15 years now. It has in-depth research on internal and external wall mortar products, and it can be said that it has accumulated richer relevant experience.
Now I want to write down these experiences. Everyone learns and progresses together. I didn’t want to write because I didn’t want to tell others about my accumulated experience.
Now, I want to open it up and write it out for your reference. Let us make progress together.
I will talk about my understanding of the dry mortar formula from the following points:
1. History of dry mortar
When I entered the field of external thermal insulation in 2005, dry mortar was still a new term. At that time, two-component adhesive mortar, plastering mortar, and tile adhesive were mainly used. The dry mortar was just beginning to be promoted.
The competition between liquid mortar and dry mix mortar is fierce. The finished liquid mortar said that dry mortar is poor water resistance, poor flexibility, and high cost.
The dry mortar said that liquid mortar is not easy to transport and store, and the proportion cannot be controlled on-site.
Later, driven by national policies, dry mortar defeated liquid mortar, but in some areas with high requirements, such as external wall flexible putty, liquid mortar was also used, but the impact was already very small. Since then, all the dry mortar has come to dominate the world, and all I heard are advantages, no shortcomings, and they are irreplaceable.
From this fact, we can see that the finished liquid mortar itself is not wrong, because there is dry mortar, so it is replaced. Any product has advantages and disadvantages, technology is constantly improving, and people's concepts are constantly changing.
Dry mortar is an imported product. When I first entered the industry, I often participated in dry mortar technical exchange meetings, or technical personnel of multinational companies regularly conducted technical explanations and exchanges. All the information came from them, and the basic formula of the technology was also they provide, At that time, a formula was still very mysterious, at least seven or eight kinds of raw materials. Looking back now, more than these, including industry standards, are all set by them. (It is worth learning from first-class companies to set standards).
Now, dry mortar formula strips mysterious clothes, any raw material supplier will give you a variety of formulas, each company has formed its own formula system after the previous accumulation, we need to choose and practice the formula that suits you. The system of dry mortar is basically mature, with a series of products such as adhesive mortar, plastering mortar, ceramic tile adhesive mortar, joint mortar, self-leveling mortar, internal and external wall putty, plastering plaster and so on.
2. Respect your predecessor
When you get the formula he developed from your predecessor, you must treat it with gratitude and awe, carefully analyze it, and treat it with caution. Since this product has been applied for a long time and is relatively stable, your predecessor must have put a lot of effort into it, which naturally has many advantages. When you can easily reduce the cost by 20% or even 50%, you must first ask yourself if you have overlooked something, otherwise, you may make mistakes.
Remember, don't take anyone lightly.
3. Clarify your responsibilities
The responsibilities of R&D engineers can be summarized simply: "Develop new products, optimize product performance, reduce product costs, and maintain product quality and stability."
To develop new products, the most important thing is to develop products with excellent performance in the shortest time. Never pursue perfection, so that you can’t develop them slowly. You should know that new products generally have higher profits. As long as the company has profits, you can make money with products. If you have been pursuing perfection, the market has long been occupied by others.
Optimizing product performance and reducing product costs are the most basic tasks of R&D engineers. This is a contradictory thing. It is the most demanding of every boss to think of low cost and good performance.
In the early stage, you can optimize it by doing more experiments. After the formula is stable, it is recommended that you keep the product quality stable, and don’t reduce the cost indefinitely, so that the product quality is getting worse. In the end, as long as high-quality products can survive in the market.
Maintaining stable product quality is the most important job for R&D engineers. It seems simple, but it is the most difficult and important. Stable product quality is the source of company profits. The raw materials will change, the production machine will be unstable, and the seasons will also change. As R&D engineers can anticipate these problems and propose solutions in advance or when problems arise, it is excellent.
R&D engineers, especially newly-entered engineers, are prone to falling into the trap of cost reduction. They are constantly reducing costs, but they do not know that the cost of products is decreasing and the quality is continuously decreasing. Ultimately, they bring endless quality complaints. Remember, there is no free lunch in the world, everything comes at a price.
4. Know your research object
The raw material of dry powder mortar is our research object. Only if you have an in-depth understanding of it can innovation be possible.
Cement: Ordinary silicon cement, aluminate cement, sulfoaluminate cement, label (32.5/42.5/52.5)
Sand: washed sand, quartz sand, crushed sand, tailing sand, etc.
Filler: heavy calcium, fly ash, slag, silica fume, etc.
Cellulose ether: varieties (MC, HPMC, HEMC), viscosity
Rubber powder: type (ethylene vinyl acetate (EVA), acrylic acid, styrene, tertiary carbonate-ethylene-vinyl acetate ternary copolymerization), film forming temperature, glass transition temperature, etc.
Others: water reducing agent, early strength agent, antifreeze agent, defoaming agent, thixotropic agent, air entraining agent, fiber, lignin, etc.
Only by thoroughly understanding the performance of raw materials can we be innovative. For example, cement is a gray powder in the eyes of others, but in the eyes of R&D engineers, it should be a mixture of tricalcium silicate, dicalcium silicate, tricalcium aluminate, tricalcium iron aluminate, gypsum, and filler.
5. What are we doing
What we are doing, we are not simple mix mud, we are not simple craftsmen, don't look down on yourself.
The field of dry mortar is a very complex field and an under-recognized field. It is not as mature as paint products. Many reaction principles are too complicated and have not been studied. Dry mortar belongs to the field of polymer cement mortar. The in-depth mechanism requires a lot of energy to study.
In the field of dry powder mortar, our overall level is still very low, basically staying in the trial and error stage, which requires us to conduct a large amount of data accumulation to standardize and improve the development of the industry.
6. Be more demanding on yourself
I personally think that the overall level of the dry mortar industry is relatively low, and the laboratory conditions of general enterprises are also very limited. Even the laboratories of large-scale enterprises are only stuck in basic mechanical performance tests, and the basic experimental means are trial and error experiments. The lack of the most basic material design and experimental design, even if it is the most basic orthogonal test design.
It is suggested that the dry mortar can be explored in the following aspects:
6.1 Experimental design
Introduce advanced test design methods and establish standardized test procedures. For example, orthogonal design, uniform design, etc. In fact, from the perspective of test design, the optimization of the formulation of dry mortar is to find the most advantageous test. There are many experimental design methods available.
6.2 Material design ideas
The trial-and-error experiment is the first-level experiment. After a certain amount of data is accumulated, the introduction of material design ideas and the use of advanced testing instruments will have great benefits for the industry and its own improvement.
6.3 Broaden your mind
The basis for broadening the mind is experience and knowledge. The key is to change your mind, don’t stay where you are.
7. Some methods for adjusting the formula of dry mortar:
First, it is easy to adjust a recipe that meets the standard, if you do not consider the cost!
A good formula must first have good constructability. If the constructability is not good, its performance cannot be fully exerted.
Secondly, to have good adaptability, the environment of the construction site is not 23 degrees Celsius, 50% humidity, and good formulas need to be adjusted according to different seasons.
Thirdly, the price is reasonable, and cost reduction is not simply a sacrifice of product performance. Maybe you can consider the solution to the problem from the other side. For example, in winter, the setting time of the mortar becomes slower. Generally, an early strength agent is added to the formulation,so your cost will increase; But if you reduce the amount of cellulose ether, you can also make the setting time of the mortar faster, so that your cost will be reduced; For how to choose, it's according you.
Fourth, a good formula must be simple. Any kind of material has advantages and disadvantages. It is not a necessary raw material. Try not to add it, which can make production simple and reduce costs.
Finally, a good formula must have a certain insurance factor, and do not blindly reduce costs, because there is a certain gap between the experiment and the actual production and site construction.
The above are some thoughts for dry mortar, I have done in this industry for 15 years. I hope to share learning and progress with you.