Tunnel use, dry spray? Wet spray? Which one is better?

Tunnel use, dry spray? Wet spray? Which one is better?

With the development of the country's economy, more and more attention has been paid to transportation. Various regions are scrambling to build roads to accelerate economic development, and the development of tunnels has also appeared in front of the people more and more. With the development of tunnel construction, the concrete used for tunnels The pump has also been valued by the market. There are two spraying methods, dry spraying and wet spraying, which one is better? Qingke Heavy Industry can briefly sort out the advantages and disadvantages of dry spraying and wet spraying for everyone.

1. It is the first choice for everyone to understand what is dry spray and what is wet spray:

1. Dry spraying: first dry mix the concrete (sandstone, cement, including powder accelerator) evenly on site, then put it into the dry spraying machine, and rely on pneumatic (compressed air) to send the dry mixture to the spray pipe through the rubber hose , The nozzle is connected with a water pipe, the dry mixture is mixed with water in the nozzle, and then sprayed out from the nozzle, relying on the injection pressure, the concrete is bonded to the surface of the rock or other materials, and quickly condenses and hardens.

2. Wet spraying: In addition to non-accelerating coagulants, the concrete is pre-prepared and produced at the mixing station, and then transported to the construction site by a concrete tanker, loaded into the wet spraying machine, and the wet-mixed concrete is sent to the nozzle through the rubber hose, and the nozzle is connected to the nozzle. There is a water pipe, which can be fed with a liquid quick-setting agent. The wet-mixed concrete and the quick-setting agent are mixed in the nozzle, and then sprayed out from the nozzle.

Second, the advantages and disadvantages of dry spray

1. Advantages: The equipment is relatively small and flexible. The price is lower than the wet spray machine.

2. Disadvantages: ①The sealing structure is not good, and the dust pollution is serious; ②Serious air leakage, easy to block the pipe, and the injection efficiency is low; ③The amount of rebound is large, and the waste of materials is serious; ④The accessories are severely worn, the loss is large, and the cost of accessories is high; ⑤Powder accelerator is artificially added, which is uneven and increases the amount of rebound; ⑥Because of the loss of cement dust, uneven water addition and large rebound amount, the mix ratio of concrete is changed and the quality of concrete is reduced. Concrete dry spraying machine = high cost + pollution + poor concrete quality = backward technology + backward concept, this kind of dry spraying machine is a technology more than 20 years ago, and it has fallen behind. The quality of sprayed concrete fluctuates greatly (manually control the amount of water added), the rebound rate is high (large waste), the construction efficiency is low, and the construction environment is relatively harsh. Dry spraying is more suitable for small volume projects. Due to the above shortcomings, wet spraying machines are generally required to be used in engineering construction, and dry spraying machines are gradually eliminated.

Third, the advantages and disadvantages of wet spray:

1. Advantages: The quality of sprayed concrete is stable, the construction efficiency is high, and the rebound rate is low.

2. Disadvantages: ①The use of liquid accelerator increases the construction cost, and the price of liquid accelerator is 3-4 times that of powder accelerator; ②The pungent smell and corrosiveness of liquid accelerator are easy to damage the construction The body of the personnel is injured, and the workers are unwilling to use it; ③The rotor type wet spraying machine is easy to block the pipe due to serious air leakage, and the spraying efficiency is low; ④The piston type wet spraying machine is expensive; ⑤The transportation of wet concrete mixture is troublesome, and even Add concrete tank trucks and other equipment; ⑥After each spraying operation, it must be cleaned with water, which is troublesome to maintain; ⑦The accessories are seriously worn, the loss is large, and the cost of accessories is high. Equipment investment is relatively large. Wet spraying is more suitable for large volume projects. The price is higher than dry spray. The accelerators used are different, and the unit price per ton for wet spray is much more expensive than that for dry spray.

Co-Nele Group has been focusing on the concrete pumping business for 20 years, and its branch company specializes in R&D and production of wet spraying machines. The SPJ08-07-22 concrete wet spraying machine produced by it has the following technical advantages, which can reduce the shortcomings of the traditional wet spraying process, provide better service and better quality assurance.

1. The centralized lubrication system is adopted, which effectively prolongs the service life of wearing parts and better protects the equipment.

2. Originally imported Eaton valve group and split piston, the quality of accessories is more guaranteed, so that you can use it with confidence and buy with peace of mind.

3. Accelerator addition and control technology: domestic famous brand metering pumps measure more accurately, and the mixing of atomized jet and nozzle material makes the accelerator and concrete mix more evenly. 6