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1. If the water capacity larger the better
During the process of buying and using the truck,the customers always think that the spraying water truck of large quantity is better , but when using it ,they complaint about the short spraying distance ,more adding water times, increased oil cost as working, payout expense increases and the society economy quality is not good .
The main function of the water truck is to lower the temperature, reduce the ash and clean the air. If the spray quality is too large, it will cause part of the ground catchments ,and part of the catchments will flow into the cloacae ,make the waste of water resource and economy ; If there is to much earth on the road , it will come into mud. And because of the tire’s conglutination of the vehicle ,it will easily cause the pollution’s extension and when it dry, it will form large area’s dust and pollution.
on account of the reasons above, the watering work must be taken after cleaning the ground. It will be difficult to clean the road after watering the road which is Seriously polluted. So it‘s not good to water too much to the ground.
(The outlet water capacity of water truck produced by Cheng Li special Automobile Company can be adjusted freely according to your requirement.)
2.Quantitative analysis of the sprinkling amount
It is described above to synthesize,large amount sprinkling water of water truck is not well instead, but if the sprinkling water amount is too small,it won’t do execution
Then, how to confirm the practical and economic sprinkling water amount of water truck? Take the DongFeng EQ1092 ’ Or EQ1092F19DJ) rated loading capacity 5t water truck to carry on computational analysis for an example.
Performance parameter:
发动机转速范围 ne 1200－3000 r／min
变速器速比 ik
一档 i1 7.31
二档 i2 4.31
三档 i3 2.45
取力器速比 iT l.373
水泵
额定转速 nP 1450 r／min
流量 Q 60 m3／h
扬程 H 60 m
轴功率 N 16 kw
按水泵额定转速计算得出：
发动机转速 n 1991 r／min
一档行驶速度 Y1 7.22 km／h
二档行驶速度 Y2 12.24 km／h
三档行驶速度 Y3 21.53 km／h
洒水车技术要求的行驶速度为5－20km／h且实际应用均在l－3档行驶作业，所以不计算高速行驶下的酒水量。
在水泵额定转速下，满载5t，洒水作业时间t：
t=5min
在水泵额定转速下，满载洒水车洒水作业距离S：
一档 S1＝602m
二档 S2＝1020m
三档 S3＝ 1794m
在水泵额定转速下，满载洒水宽度14m，其平均
洒水量q ：一档 q=0.59L/m2
二档 q=0.35L/m2
三档 q=0.20L/m2
在水泵额定转速下，洒水量仅与水泵流量成正比。
按一档平均洒水量最小，核算对照表1。
表1 一档时水泵流量与洒水量对照表
|
水泵流量（m3/h） |
洒水量（L/m2） |
|
40 |
0.39 |
|
50 |
0.49 |
|
60 |
0.59 |
|
80 |
0.79 |
|
100 |
0.98 |
|
203 |
2 |
按三档平均洒水量最小，核算对照如表 2
表2 三档时水泵流量与洒水量对照表
|
水泵流量（m3/h） |
洒水量（L/m2） |
|
40 |
0.13 |
|
50 |
0.17 |
|
60 |
0.20 |
|
80 |
0.27 |
|
100 |
0.33 |
|
203 |
0．68 |
根据以上计算并结合洒水作业实际状况，认为在三档行驶速度下，洒水量最小以 0．15－ 0．25L／m2为宜；在～档行驶速度下，洒水量最大以0．5－ 0．7L／m2为宜。所以笔者认为选择洒水车水泵流量以60m3／h为最佳技术经济性选择，也是最佳社会经济性选择。
3. The analyses about the standard of water truck
According to the requirement of QC/T29114-9《Technology Qualification Of Water Truck》 ,at the spraying width ≥ 14m , its watering quality is 0.2-2L/m2 ,means that the height of water column is 0.2-2mm2 per area . Having counted that when its quality reaches 2L/m2 ,width of 14m, the pump ‘s flux approaches 203 cubage per hour. Such a high flux won’t exist in or out of China. Obviously the standard of Max. spraying quantity is too high and impractical.If we take 1L/m2 as the Max. spraying quantity, the water truck of water pump flux up to 100m3/h can achieve the requirement , but it’s not economical. And if we put it into practice, the water on the road can’t be all absorbed or vaporized, the water will flow everywhere, result in the waste of resource. So we must combine the fact to establish the scientific and reasonable technique requirement .
4. Why do the customers require the larger spraying quantity water truck ?
The standard consumer water flux is 80m3/h, but they still require the larger water flux, what’s the reason ? By diagnoses , the lack of water trucks and money
Makes the large quantity flux of the water truck, they hope to keep the ground wet for a long time and to give the citizens a sense of having been watered for not long. The watering work can decorate the city and it’s a way to welcome the leaders and the guests.
Lacks of money always make the truck rest in hot summer , can’t function effectively. This kind of state must be changed and make the water truck play a role in purifying and beautifying in the urban construction.
5. The opinion of strengthening the width of sprinkling water deserves to support
At present, domestic watering width of watering truck is generally in 14- 16m, but with the development of widening road and expressway, the demand of sprinkle water width larger than 20m is the voice that producer can often hear already. But the only improvement of water pump lift and strengthen of water pressure raise about the width of sprinkling water , not only strengthen the cost, but also the oil consumption, social economy is not good.
简单而又实用的办法就是提高后喷嘴的距地高度。根据平抛运动原理，若流速不变，其射出距离与距地高度的平方根成正比。若喷嘴距地高度为0．7m，双喷嘴喷洒宽度为14m；若喷嘴距地高度为l．4m，则双喷嘴洒宽度可达成19．8m；若喷嘴距地高度为2.8m，则双喷嘴洒宽度可达28m，但此时的洒水量也是反比例下降。
To improve the height of the nozzle from the ground, can not only improve the widths of the spraying effectively , but also to make the function about reducing the temperature, pressing ash and cleaning air obviously.
This new and pragmatic nozzle of high frame will be popular in the society.
6洒水系统的压力估算
根据流体力学原理，水头损失包括沿程水头损失印局部水头损失。沿程水头损失与管长、流速的平方成正比，局部水头损失与流速的平方成正比。所以选择合适的管径来调整流速，是降低水头损失的关键。
在流量确定后，可参考表3选择管径。
表3 管路直径与最大流量限制表
|
最大流量（L/S） |
管路直径（mm） |
最大流速（m/s） |
|
1 |
25 |
2.4 |
|
2.5 |
38 |
1.69 |
|
4.17 |
50 |
2.01 |
|
6.67 |
65 |
2.12 |
|
10.0 |
75 |
2.26 |
|
18.4 |
100 |
2.33 |
|
30.0 |
125 |
2.44 |
|
43.0 |
150 |
2.45 |
备注： 超过此限，其水头损失显著增加
直管水头损失可参表4
表4 100m 直管水头损失简表 m
|
管径
（mm） |
|
|
1 |
2 |
4 |
6 |
8 |
10 |
15 |
20 |
25 |
30 |
40 |
50 |
60 |
|
25 |
32.7 |
|
|
|
|
|
|
|
|
|
|
|
|
|
38 |
3.5 |
14 |
55 |
|
|
|
|
|
|
|
|
|
|
|
50 |
0.8 |
3.1 |
13 |
29 |
|
|
|
|
|
|
|
|
|
|
65 |
|
0.8 |
3.2 |
7.1 |
13 |
20 |
|
|
|
|
|
|
|
|
75 |
|
0.4 |
1.6 |
3.3 |
5.9 |
9.6 |
21.6 |
|
|
|
|
|
|
|
100 |
|
|
0.4 |
0.8 |
1.3 |
2.1 |
6.8 |
8.6 |
13 |
19.4 |
|
|
|
|
125 |
|
|
|
0.23 |
0.4 |
0.63 |
1.3 |
2.7 |
4.1 |
5.9 |
10.7 |
|
|
|
150 |
|
|
|
|
0.16 |
0.26 |
0.58 |
1.1 |
1.6 |
2.3 |
4.2 |
6.4 |
9.4 |
备注：旧管加倍
计算局部水头损失可参考表5
表5 折合管路直径倍数简表
|
类别 |
折合管路直径倍数 |
备注 |
|
全开闸阀 |
13 |
未全开加倍 |
|
标准弯管 |
25 |
拼制加倍 |
|
逆止阀 |
100 |
|
|
底阀 |
100 |
部分淤塞加倍 |
Take the standard ￠50mm siphon for example, synthesize ￠50mm×25=1.25m straight pipe, if the flux is 6L/S, damnify 29m per 100m water ,0.36m per ￠50mm
通过洒水车水头损失测算，后喷洒水头损失约为13m，前冲洗与射枪的水头损失各约为10m。洒水车技术条件要求：洒水工作压力≥250kpa ，射枪与冲洗工作压力 ≥300kpa。为保证冲洗及洒水同时工作的压力要求，考虑水头损失，其水泵杨程应不小于45m，所以洒水车选择扬程最大为60m的水泵即可。
7 洒水作业时为何要停车换档
洒水车不进行洒水作业时，其行驶速度的调整均可实现顺利换挡，其取力器不影响变速箱同步器的同步性。当洒水作业时，取力器直接驱动水泵，当踏下离会器换挡时，由于水泵较大的扭矩，迫使变速器动力输出齿轮转速迅速降低，造成换挡不能进行，迫使停车才能换挡。
If we install the clutch between the power take off and water pump, it can realize the gears of sprinkle water work without parking.
8. Comprehensive technological economy of the water truck
The wate truck manufacturer should improve the advancement and practicability of technology, simplifies the circuit and it will be easy to overhaul, especially choosing the water pump of the high-efficient, low power,wii reduce user’s oil consumption in the course of using, realize better social economy .Though the sprinkling water amount of the water truck is heavy and the pressure is high, the water pump is large in power, consuming the fuel more, users are uneconomical in long term administration, social economy is bad. So users buying wate truck should study knowledge, improve the engineering level, analyze on the comprehensive technological economy to water truck of every producer and choose cheap, fewer oil consumption wate trucks of fine quality.
The water pump technical parameter of watering lorry flux 60m3/ h, lift 60m, efficiency not smaller than 60% is appropriate. Demanding water pump in annotate state that sucking height not smaller than 4m, this is not only suitable for the open-air project homework but also suitable for sucking the clear water in the canal of urban river, in order to save running water resources.
While setting up fire hydrant we should consider about the urban water supply spot, to reduce and save the finance payout .
Sprinkle and water after cleaning the urban road to prevent the mud from silting the wayside sewage and causing the water accumulation, it saves municipal management expenses of often digging.
Impro | 
