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常見的幾種渣漿泵性能曲線
    (1)平坦的Q- H曲線:如圖2-43曲線d所示。這種性能曲線適用于流量調節范圍較大，而壓力要求變化較小的系統中?？梢栽谝欢ǚ秶鷥绕鸬阶詣泳S持液面和壓力的作用，如鍋爐給水泵、消防泵。

(2) 陡降的Q-H曲線:如圖2 - 43曲線c所示。這種性能曲線適用于在流量變化不大時要求壓頭變化較大的系統中，或壓頭波動時要求流量變化不大的系統中。例排灌泵站中，輸送纖維漿液的系統中用泵。

(3)有駝峰的Q-H曲線:如圖2 - 43曲線a所示。這種性能曲線，泵在駝峰區運行時會出現不穩定工況。當有駝峰的性能曲線a與裝置特性曲線b會交于兩個點，而不是一個點，使泵處于不穩定工況，影響泵的安全運行。所以對于有鴕峰的化性能曲線，一 般規定工作點的揚程必須小于關死揚程，以免泵在不穩定工說運行。
二、流量-功率曲線(Q-P)
    流量-功率曲線(Q-P) 是表示泵的流量與軸功率之間關系的曲線。泵的軸功率是泵的水功率P,和機械損失功率AP之和，泵的水功辛P.可用下式計算:
    根據泵的性能曲線，計算出流量與水功率的關系曲線，如圖2 -40中Q'-Pr所示，加上對應流量點的機械損失功率，就可得到流量與軸功率的關系曲線Q' -P，對每一個流量Q'值減去相應的容積損失，即可得到泵的實際流量-軸功率曲線(Q -P)。
三、流量效率曲線(Q-η)
    流量-效率曲線是表示泵流量與效率之間關系的曲線。根據泵的Q -H曲線和Q-P曲線上的相應點，可得到泵的流量-效率曲線Q一η?？梢钥闯?/span>Q一η曲線是由坐標原點出發的一條拋物線，最高點m的流量Q，為設計工況點(即額定流量點)， 當Q<Qp 時效率η是隨流量Q的增加而增加。當Q>l,時，效率η是隨流量的增加降低了，所以泵應使用在額定流量時最為經濟。渣漿泵配件

Q-H curve with hump: as shown in Figure 2-43 curve a. This performance curve, the pump in the hump area operation will appear unstable conditions. When there is a hump performance curve A and device performance curve B will intersect at two points, rather than one point, so that the pump is in an unstable condition, affecting the safe operation of the pump. Therefore, for the chemical performance curve with peak, generally, the head of the specified working point must be less than the shut-off head, so as to avoid the pump running in unstable operation.

II. Flow power curve (Q-P)

Flow power curve (Q-P) is a curve showing the relationship between pump flow and shaft power. The shaft power of the pump is the sum of the water power P of the pump and the mechanical loss power AP, and the water power P of the pump can be calculated by the following formula:

According to the performance curve of the pump, calculate the relationship curve between flow and water power, as shown in Q & apos; - PR in Fig. 2-40, and add the mechanical loss power of the corresponding flow point to get the relationship curve Q & apos; - p between flow and shaft power. Subtract the corresponding volume loss from each flow Q & apos; value to get the actual flow shaft power curve (Q-P).

III. flow efficiency curve (Q - η)

The flow efficiency curve is a curve showing the relationship between pump flow and efficiency. According to the Q-H curve and the corresponding points on the Q-P curve, the flow efficiency curve q-η can be obtained. It can be seen that the q-η curve is a parabola starting from the origin of the coordinate, and the flow Q at the highest point m is the design operating point (i.e. rated flow point). When Q < QP, the efficiency η increases with the increase of flow Q. When Q > L, the efficiency η decreases with the increase of flow, so the pump should be used at rated flow.