真空引水罐冻裂了怎么办？
最近很多地方正在经历一场温度较低的严寒，二九天天寒地冻，像上海等一些江南城市已经多年没遇到过零下八度的低温天气了。“数九”又称“冬九九”（shǔjiǔ），是中国冬季一种民间节气。“数九”从内每年阳历12月下旬初容“冬至”的次日开始。“数九”习俗起源于何时，现在还没有确切的资料。不过，至少在南北朝时已经流行。梁代宗懔《荆楚岁时记》中就写道：“俗用冬至日数及九九八十一日，为寒尽。”数九寒天，就是从冬至算起，每九天算一“九”，一直数到“九九”八十一天，“九尽桃花开”，天气就暖和了。还有首歌是这么唱的：一九、二九不出手；三九、四九冰上走；五九和六九，河边看杨柳；七九河开，八九雁来；九九加一九，耕牛遍地走。
如今科技发达了，天气预报也能够很早预测这种恶劣天气了。虽然天气预报早就提示低温天气的来临，但是智者千虑尚有一失。最近，有多位用户陆续反映水管冻裂了、水泵泵体冻裂了、真空罐引水罐冻裂了，前两者我们之前的文章中已谈过，今天来说说真空引水罐冻裂了怎么办？
首先我们来说说真空引水罐的工作原理：
使用前，真空罐必须注满水。当真空引水罐内的水被泵吸出时，罐内产生负压（真空）或由真空泵强制。由于大气压力的影响，储液罐中的水通过吸入管进入真空罐，由泵连续供水或启动离心泵。
特点及适用范围：
真空引水罐用于无自吸功能的下吸式（低水高泵）水泵。ALIWATER真空引水罐结构独特，真空度高，保证了水泵的高工作效率，取代了真空引水泵。体积可由下列公式确定：（L+H）×s≤0.14v或V≥7（L+H）×s
式中l——吸水管垂直高度（吸水管垂直高度不大于6m）与水平长度之和；
H——真空引水罐高度；
S——吸入管截面积；
V——真空引水罐总容积。
我们来谈谈ALIWATER真空引水罐的使用
一、根据图纸连接吸入管、真空罐和水泵。
二、松开水箱上方的铜旋塞或在此连接真空泵，打开水箱上方进水口的盲板法兰，向水箱中加入清水。当铜旋塞有稳定的水流出时，紧固盲板，拧紧铜旋塞。
三、确认无泄漏后，启动水泵，投入正常使用。
根据理想气体的波义耳定律，P1*V1=P2*v2
P1：大气压力（计算绝对压力，取1bar左右）
V1:真空罐进口管容积+无效容积
P2:真空罐运行时的压力，一般为负压（如吸入压头为3米，则为0.7巴）
V2:真空罐进口管容积+无效容积+有效容积
由于实际操作过程中有多个因素（如管道损耗、溶解气体等），我把真空罐做大了，一般系数为1.5~2.0。
ALIWATER真空引水罐又称虹吸桶、真空桶、引水罐等，利用密闭容器的真空可产生吸力的原理,配合钛龙离心泵使用可产生自吸效果(等同于VAREM自吸泵),最大自吸高度4m左右。真空引水罐的优点是组装方便,泵头容易维护。真空引水罐冻裂一般是在罐体与封头接缝处，我们可以采用电焊的方式，将其漏点打磨后补焊，补焊后再打磨平整，用气泵试压。最后再刷上防锈漆和面漆，以确保后期使用时不会过分生锈。
另外，在初次运行时，应尽量将ALIWATER真空引水罐注满水；保证泵进口前端、泵体及机械密封的密封性能；在泵出口处安装止回阀；泵进口处管道需向下倾斜；泵送时控制吸入。如需了解更多关于ALIWATER真空引水罐的技术问题，欢迎与上海龙亚真空引水罐技术部洽谈。
How to do if the vacuum diversion tank is cracked?
Recently, many places are experiencing a cold weather with low temperature. It's freezing every day in February and September. Some cities in the south of the Yangtze River, such as Shanghai, haven't experienced a low temperature of minus eight for many years. "Shujiu", also known as "dongjiujiu" (SH ǔ Ji ǔ), is a folk solar term in winter in China. "Number nine" starts from the next day of "winter solstice" in the late December of the lunar calendar. There is no exact information about the origin of the custom of counting nine. However, it was popular at least in the northern and Southern Dynasties. "The winter solstice days and 9981 days are commonly used for cold exhaustion," wrote Liang Daizong Counting nine cold days means counting "Nine" every nine days from the winter solstice until the eighty-one day of "Nine", when "nine peach blossoms bloom", the weather will be warm. There is also a song that goes like this: no action in nineteen ninety-nine or nineteen twenty-nine; walking on the ice in thirty-nine or forty-nine; watching willows by the river in fifty-nine or sixty-nine; wild geese coming in eighty-nine when the river opens in seventy-nine; cattle walking all over the land in ninety-nine plus one nine.
With the development of science and technology, the weather forecast can predict this kind of bad weather very early. Although the weather forecast has long suggested the coming of low temperature, the wise man still has some mistakes. Recently, many users have reported that the water pipes, the pump body and the vacuum tank are cracked. We have talked about the first two in previous articles. Today, what should we do if the vacuum tank is cracked?
First of all, let's talk about the working principle of the vacuum diversion tank
The vacuum tank must be filled with water before use. When the water in the vacuum water diversion tank is pumped out, negative pressure (vacuum) is generated in the tank or forced by the vacuum pump. Due to the influence of atmospheric pressure, the water in the liquid storage tank enters the vacuum tank through the suction pipe, and the pump continuously supplies water or starts the centrifugal pump.
Features and scope of application:
The vacuum water diversion tank is used for the downdraft (low water high pump) pump without self-priming function. The unique structure and high vacuum degree of aliwater vacuum water diversion tank ensure the high working efficiency of the pump and replace the vacuum water diversion pump. The volume can be determined by the following formula: (L + H) × s ≤ 0.14v or V ≥ 7 (L + H) × s
Where l -- the sum of the vertical height of the suction pipe (the vertical height of the suction pipe is not more than 6m) and the horizontal length;
H -- height of vacuum diversion tank;
S -- sectional area of suction pipe;
V -- total volume of vacuum water diversion tank.
Let's talk about the use of aliwater vacuum diversion tank
1、 Connect the suction pipe, vacuum tank and water pump according to the drawing.
2、 Loosen the copper cock above the water tank or connect the vacuum pump here, open the blind flange of the water inlet above the water tank, and add clean water into the water tank. When there is stable water flowing out of the copper cock, tighten the blind plate and tighten the copper cock.
3、 After confirming that there is no leakage, start the water pump and put it into normal use.
According to Boyle's law of ideal gas, P1 * V1 = P2 * v2
P1: atmospheric pressure (calculated absolute pressure, about 1bar)
V1: volume of vacuum tank inlet pipe + invalid volume
P2: pressure of vacuum tank during operation, generally negative pressure (if suction head is 3M, it is 0.7 bar)
V2: volume of vacuum tank inlet pipe + invalid volume + effective volume
Due to many factors (such as pipeline loss, dissolved gas, etc.) in the actual operation process, I enlarged the vacuum tank, and the general coefficient is 1.5 ~ 2.0.
The frost crack of vacuum water diversion tank is generally at the joint between tank body and head. We can use electric welding to grind the leakage point and then repair it. After repair welding, grind it flat again and use air pump to test pressure. Finally, the antirust paint and topcoat are applied to ensure no excessive rust during later use.
In addition, during the initial operation, the airwater vacuum diversion tank should be filled with water as much as possible; the sealing performance of the pump inlet front end, pump body and mechanical seal should be ensured; the check valve should be installed at the pump outlet; the pipeline at the pump inlet should be inclined downward; the suction should be controlled during pumping. If you need to know more about the technical problems of aliwater vacuum diversion tank, you are welcome to discuss with Shanghai Longya vacuum diversion tank technology department.