原文：
近年来，随着给排水事业的发展，泵站中所用设备的生产也迅猛发展，一大批新型设备相继问世，取代老式型号产品。各生产厂家到处推销， 但各种产品的质量、性能差距很大，鱼目混杂。因此，很多企业对“给排水泵站所需设备”选型及采购，也采用了招标方式。下面我谈一下在“给排水泵站所需设备”招标 采购 中的几点体会，供大家参考。

          一、水泵的选择 　　在编制水泵招标文件时，除满足流量、扬程等主要技术参数要求外，还要从节能的角度来考虑水泵的数量、选型等问题，而水泵种类可分为离心泵、混流泵、轴流泵、潜水泵等，就其结构形式上又分为卧式泵和立式泵，其中离心泵以流量和扬程范围较大而广泛用于泵站设计中，而轴流泵属于大流量、低扬程范畴，混流泵介于两者之间，潜水泵以其构造简单、维修安装方便、性能可靠、节能省电、节省基建费用等优势，离心泵 已在我国得到广泛的应用，笔者认为在编制水泵招标文件时应注意以下三点：

          1、水泵数量要适中 水泵数量太多 ，泵房规模必然加大，同时多台泵并联工作量折减，浪费能量，势必增加工程投资；水泵数量太少，在流量变化较大又不利于用调整泵开启数的方法来控制流量时，只能用闸门控制，这样势必造成能量损失，因此应根据实际情况选择水泵数量。如果水量变化大可多选几台泵； 反之， 可适当加大泵型，减少泵的台数，以降低工程投资。

         2、根据水位变化选泵 凡是与水体直接联系泵站水泵扬程都与水体水位变化有直接关系 ，如果水源水位变化较小，水泵扬程的选择比较容易，反之难度较大。例如：松花江水位变化幅度在 7m 左右，设计者为保险起见，往往根据大流量、深井泵高扬程同时发生的参数选择水泵， 实际上二者同时发生的机率很少，常水位发生的机率较大， 而这时所选的水泵扬程显然过高，迫使水泵偏离高效区工作，由此造成的电能浪费是很严重的。解决的办法是认真分析水位变化频率，以经常发生的水位作为选择水泵扬程的依据，选择叶轮角度可调的水泵，在较小范围内解决扬程变化问题，在扬程变化较大时，可采用自己配备不同扬程水泵的方法加以解决，以保证水泵在各种水位均能在高效区工作，以充分发挥水泵的能量。

         3、根据泵站工艺选用水泵 水泵从结构形式上讲可分为立式泵、卧式泵和潜水泵。立式泵占地面积小 ，但由于电机安装在水泵上方，运行不够稳定，并且种类较少；卧式泵占地面积大，运行稳定， 种类很多，选择范围较大； 潜水泵占地面积小、安装方便、运行稳定、维修方便、种类多，但在寒冷地区冻季运行检修要有保温措施。笔者认为，对于合建式取水泵站宜选用立式泵或潜水泵，因为取水泵房建在水中，一般需采用沉井法或围理法施工，难度较大， 选用立式泵或潜水泵可减少泵房面积，大大压缩工程投资。另外，对于一些需要增加水量而原泵房面积又需保持不变的泵站改造项目，增加水泵数量有困难，也可将原卧式泵改为立式泵或潜水泵，以达到在原面积不变的前题下增加水泵数量从而增加水量的目的。

          二、水泵的辅助设备的选择 1、闸阀的选择 近年来，闸阀作为控制水量和水流方向的一种工具 ，其形式也发生了变化。过去常用的手电两用闸阀逐渐被手电两用蝶阀所取代，蝶阀的优点是体积小、重量轻 、安装方便、阻力系数小。 缺点是如果加工安装精度不够， 或水中杂质较多时易导致蝶阀关闭不严出现漏水现象，而传统的闸阀虽不易漏水，但体积大；尤其是管径大的闸阀，又大又笨重， 安装拆卸都不方便；更重要的是，由于体积大， 导致泵房面积增大，工程造价提高。

         因此在泵站设计、招标选用阀时应考虑以下两方面的问题： （1）使用场合 使用不受场地限制、水中杂物较多、易堵塞重要位置的阀 ，可采用手电两用闸阀；反之可采用蝶阀，尤其用在泵房改造工程中可采用蝶阀，以便有效利用原有泵房的空间，达到在原泵房面积不变的前提下提高供( 排 )水量的目的。 （2）生产厂家 选用规模较大、生产年限较长、讲信誉、质量过关并且负责安装调试的阀门生产厂家。随着蝶阀加工精度的不断提高 ，质量会越来越好，漏水问题将得到解决，那时蝶阀会取代老式闸阀，这是阀类的发展趋势。 2、格栅除污机的选择 格栅除污机用于清除污水、试压泵雨水及污水处理厂进水口拦污栅上的垃圾和各种漂浮物，格栅除污机按机械结构可分为链条牵引式格栅除污机，绳索牵引式格栅除污机和弧形格栅除污机，按清污方式可分为齿耙前置式清污机、齿耙后置式清污机及自清式清污机三类。在水泵辅助设备的选择中，格栅除污机的选择是十分重要的。在编制招标文件时除应考虑上述类型外还应考虑泵站的性质（污水、雨水），建设单位要求的自动化程度，在评标时应注意选择栅条不易堵塞、阻力系数小、水流畅通、安装方便、维修管理简便、耗电量小、价格低的产品。

            三、水泵的节能问题 水泵是工农业生产和人民生活中使用十分广泛的设备，就给排水工程为例，水泵是给排水系统中主要的耗能设备，城市供水的一泵站、二泵站、加压泵站、城市排水的雨水泵站、污水泵站、污水处理厂等。其提升水量非常大，卫生泵可以达到每日几十万至几百万立方米，往往都采用大型水泵，大多数均为全天运转，电耗量很高，一般水泵的电耗占总电耗的 70%以上，在系统运行费用中居第一位。这些能耗中，有一部分多余能耗被浪费掉了，为了节能应该对水泵工况进行调节，给水排水工程中应用的水泵多为离心泵。

          离心泵的调节方法有两类：一类是通过调节水泵出口管路上的阀口来改变管路特性，实现水泵工况点调节；另一类是改变水泵的转速，从而改变水泵的特性曲线，计量泵实现水泵工况点的调节。前者节能效益较低，部分多余能量消耗在阀口上；后者是一种高效节能的调节方式，因此调节水泵转速是改变水泵工况的较好方法，选择水泵时，建议在经济条件允许的情况下，选择调节节能泵以降低电耗、减少运行成本、降低长年运行费用。对于小企业在水处理工艺选用这种方法节能也可降低运行成本，同时也适用其它工程水泵的选用。 以上是笔者在泵站所需设备招标采购中的一些粗浅体会 ， 有些问题可能还不够深入，希望和大家进一步探讨，以便在今后的泵站所需设备的招标中能为企业选用最合适的设备，以保证用最小的投入取得最大的经济效益，使我们的招标工作能达到用户满意的效果。

“ Water supply and drainage pumping stations of the necessary equipment procurement problems in the bidding ”是由中国离心泵网提供的水泵行业新闻，译文仅供参考。另外，中国离心泵网还提供相关产品搜索：离心泵型号、离心泵价格、离心泵技术、离心泵新闻、离心泵生产商等。

译文：
            In recent years, with the development of water supply and drainage, pumping station is also used in the rapid development of production equipment, a large number of new devices one after another, to replace older models. The manufacturers sell everywhere, but the quality of various products, the performance gap between the large, mixed fish head. Therefore, many enterprises, "the necessary equipment to the water pumping station," selection and procurement, but also by the tender. Now I turn to the "necessary equipment to the pumping stations," Some experience in bidding for reference. First, the choice of pump Pump in the preparation of tender documents, except to meet the flow and head requirements of major technical parameters, but also fire pumpsfrom the energy point of view to consider the number of pumps, selection and other issues, the pumps can be divided into types of centrifugal, mixed flow pumps, axial flow pumps, submersible pumps, etc., to form its structure is divided into horizontal pumps and vertical pumps, which pump to a larger range of flow and head is widely used in pumping station design, the axial flow is large, low- head area, mixed flow between them, submersible pump with its simple construction, maintenance, easy installation, reliable performance, energy saving, save infrastructure costs and other advantages, has been widely used in China, I believe that in the preparation of tender pump document should be aware of the following three points: 1, the number of pumps to moderate Large volume pumps, pump size must increase, while several pumps in parallel workload reduction, waste of energy, is bound to increase investment in public works; pump too few, which does not help in changing flow pump used to adjust the number of ways to open to control the flow, only with gate control, this will inevitably cause energy loss, the situation should be selected according to the actual number of pumps. If the water changes could choose some more pumps; the contrary, increase the pump may be appropriate to reduce the number of pump station to reduce Oil pumpsthe engineering investment. 2, according to water level changes of selected pump Any direct contact with the water pump and water pump lift water level changes are directly related to, if the water level changes a little easier the choice of pump head, otherwise difficult. For example: changes in the Songhua River water level in the range of around 7m, the designer for insurance purposes, often under high flow, high lift pump parameters simultaneously, in fact, the probability of two simultaneous small probability of occurrence of larger constant level, and then selected the pump head is too high, forcing departure from the high efficiency water pump work, the resulting energy waste is very serious. The solution is to carefully analyze the frequency of water level changes to the water level frequently the basis for selecting pump head, choose the angle adjustable impeller pumps, in the context of solving small head change, change in head is large, can use their own with different ways to solve the lift pump to ensure water level can pump in a variety of work in high areas, in order to give full play to pump energy. 3, pump selection process under the pump Pump from the structural form of speaking can be divided into vertical pumps, horizontal pumps and submersible pumps. Vertical pump small footprint, but because the pump motor is installed above the run is not stable enough, and less species; horizontal pump covers a large, stable, many types, large range of options; Submersible Pump small size easy installation, stable operation, easy maintenance and variety, but the cold season in cold regions have run the repair insulation measures. The author believes that the co-construction of water pumping stations should use vertical-type pump or submersible pump, water pump house built in the water because, generally requires the use of caisson construction method or Wai Li-fa, difficult to choose vertical pumps or submersible pumps reduce the pumping station area, greatly compressed project investment. In addition, some need to increase the water volume of the original pumping station area and the need for maintaining Bubian the Pumping Station Renovation project, increase the pump Shuliang You Kunnan can also change the original horizontal pumps vertical pumps or Qianshui pump in order to meet Yuan area is not before the title change to increase the number of pumps to increase water purposes. Second, the choice of auxiliary equipment pump 1, the choice of valve In recent years, water control valve and flow direction as a tool, its form has changed. The last common flashlight flashlight dual dual-gate valve is gradually being replaced by butterfly valve has the advantage of small size, light weight, easy to install, drag coefficient.Split case pumps Drawback is that precision is not enough if the installation process, or impurities in the water more often had strict leaking valve closure phenomenon, though difficult traditional valve leakage, but the volume is large; particularly large diameter gate valves, large and bulky , installation and removal is not easy; more importantly, are large, leading to increased pumping station area, project cost increase. Therefore, pump station design, tender selection valve should consider the following two issues: (1) Use Use of non-space is limited, debris in the water more easily plug the important position of the valve, dual valve flashlight can be used; contrary valve can be used, particularly in the Pumping Station Improvement Project with the butterfly valve can be used for the effective use of original pump room, pumping station area to change the original premise for increasing the (row) of water purposes. (2) manufacturer Choose the larger, longer production period, prestige, quality, and is responsible for installation clearance valve manufacturer. With the continuous improvement of precision valve, quality will become better and better, leakage problems will be resolved, then replace the old gate valve, which is the development trend of valves. 2, Screen Rack Selection Grate discharge machine used to remove sewage, rainwater and sewage treatment plant intake trash rack on the garbage and all kinds of floating debris, grate discharge machine according to the mechanical structure can be divided into chain tractor grate discharge machine, rope Traction Screen Rack and curved grate discharge machine, according to clean-up can be divided into front-tooth rake cleaning machine, rear harrow teeth cleaning machine and cleaning machine from the Qing style categories. The choice of auxiliary equipment in the pump, the grate discharge machine selection is very important. In addition to the preparation of tender documents should be considered outside of these types should also consider the nature of the pumping station (sewage, water), requests for building automation, evaluation should be selected in the trash rack is not easy to plug, the resistance coefficient, water flow, easy installation, easy maintenance and management, power consumption, lower price products. Third, water pump problems Industrial and agricultural production and water pump is used in a wide range of people's life of equipment, give an example drainage works, water pump to the drainage system is the major energy-consuming equipment, urban water supply of a pumping station, two pumping stations, booster pump station, urban stormwater drainage pumping stations, sewage pumping stations, sewage treatment plants. The upgrading of water is very large,Vacuum pumps can reach hundreds of thousands a day to several million cubic meters, often using a large pump, most were running all day, electricity consumption is high, the general pump power consumption of the total power consumption of 70 %, and in system operation costs in first place. The energy consumption in some extra energy is wasted, in order to pump energy condition should be adjusted, water and wastewater engineering applications as centrifugal pumps and more. The adjustment of pump there are two types: One is by adjusting the pump outlet tube on the road to change the pipeline valve port characteristics of pump operating point adjustment; the other is to change the pump speed, thus changing the pump characteristic curve of pump operating point adjustment. The former energy-efficient, some extra energy consumption on the valve port; the latter is an energy efficient way of regulation, so adjust pump speed is to change the pump working good way to select pump is recommended in the economic conditions permit Next, select the energy regulator In-line pumpsto reduce pump power consumption, reduce operating costs, lower operating costs year round. For small businesses use this method in the energy-saving water treatment technology can reduce operating costs, but also for other projects use the pump. These are the author bidding and purchasing the necessary equipment in the pumping station some superficial experience, some problems may not go far enough, and we hope to further explore in order to pump the necessary equipment in the next tender for business use in the most appropriate equipment to ensure that input with the minimum to maximize the economic benefits of the tendering exercise for us to achieve customer satisfaction results.

原文来源：http://www.1lixinbeng.com/

2010-09-01 06:56

返回