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渣漿泵經濟評價全壽命周期成本計算

全壽命周期成本(LifeCycleCosts,簡稱LCC)是指成套泵設備在整個壽命周期的總費用,通過對全壽命周期成本的比較,來確保所選擇的結構設計方案具有最佳經濟性。歐洲泵業協會和美國水力學會對全壽命周期成本的計算公式作出了規定如下:

在整個全壽命周期成本中，能源費、運行費和維修費占到了離心泵全壽命周期成本的絕大部分。圖1-87給出一臺離心泵全壽命周期成本的構成。圖1-88則給出了一臺小型離心泵采用兩種不同流量調節方式的總成本隨運行年數的變化。
四、選泵示例
    [例1-6]某成品油輸送管道如圖1-89所示,管徑為355.6mmx7.5mm,管內壁平均粗糙度為0.125mm,站間距為91km,管道沿線地形平坦(起、終點高程均為12m) ,設計輸量為

700m3/h。在輸送溫度下,油品的黏度為6X10~6m2/s,密度為844kg/m3，油品來油壓頭h1為50m,泵站站內損失壓頭h站為20m,末站油品進站壓頭h2 不小于30m。試選擇該泵類型、型號、臺數。
    (1)確定泵的類型，因輸液為輕質油品且流量較大，故選用離心油泵。

(2)確定泵提供的揚程。

解:油品流速為

3)確定泵工藝。

通過計算可知,管道輸量為700m3/h時，泵站需要提供的揚程為1209. 4m.由于管道連續運營需要設置備用泵，從經濟角度出發，選擇DY850- 125X5型泵，采用泵串聯工藝。DY850-125X5型泵的主要參數見表1-13。
    依據泵的性能參數，根據最小二乘法，單臺泵工作特性曲線為:
               h= 746.61 - 0.0002Q2
    根據泵串聯的水力特性,兩臺泵串聯后的工作特性曲線為:
              H=2h= 1493.22 - 0.00Q404
兩臺泵串聯工作后，在輸量為700m3/h時提供的揚程為:

Life cycle cost calculation of slurry pump economic evaluation

Life cycle costs (LCC) refers to the total cost of a complete set of pump equipment in the whole life cycle. Through the comparison of life cycle costs, we can ensure that the selected structural design scheme has the best economy. The European Pump Association and the American Hydraulic Institute have stipulated the calculation formula of life cycle cost as follows:

In the whole life cycle cost, energy cost, operation cost and maintenance cost account for most of the life cycle cost of centrifugal pump. Figure 1-87 shows the life cycle cost composition of a centrifugal pump. Figure 1-88 shows the total cost of a small centrifugal pump with two different flow regulation methods as a function of the number of years of operation.

4、 Example of pump selection

[example 1-6] as shown in Fig. 1-89, the diameter of a product oil pipeline is 355.6mmx7.5mm, the average roughness of the inner wall of the pipeline is 0.125mm, the distance between stations is 91km, the terrain along the pipeline is flat (the elevation of the starting and ending points is 12m), and the design throughput is

700m3/h。 At the delivery temperature, the viscosity of the oil is 6x10 ~ 6m2 / s, the density is 844kg / m3, the oil pressure head H1 is 50m, the loss head h in the pump station is 20m, and the inlet pressure head H2 of the final station is not less than 30m. Try to select the type, model and number of pumps.

(1) Determine the type of pump, because the infusion is light oil and the flow rate is large, so centrifugal oil pump is selected.

(2) Determine the head provided by the pump.

Solution: the oil flow rate is

3) Determine the pump process.

According to the calculation, when the pipeline throughput is 700m3 / h, the pump head required to be provided by the pump station is 1209.4m. Due to the continuous operation of the pipeline, the standby pump is required. From the economic point of view, the dy850-125x5 pump is selected and the pump series process is adopted. The main parameters of dy850-125x5 pump are shown in table 1-13.

According to the performance parameters of the pump and the least square method, the working characteristic curve of a single pump is as follows:

h= 746.61 - 0.0002Q2

According to the hydraulic characteristics of the pumps in series, the working characteristic curve of the two pumps in series is as follows:

H=2h= 1493.22 - 0.00Q404

After the two pumps work in series, when the throughput is 700m3 / h, the lift provided is: