标准孔板流量计是由机械加工获得的一块圆形穿孔的薄板。它的节流孔圆筒形柱面与孔板上游端面垂直，其边缘是尖锐的，孔板厚与孔板直径比是比较小的。孔板在测量管内的部分应该是圆的并与测量管轴线同轴，孔板的两端面应始终是平整的和平行的 孔板流量计误差的几大因素：1孔板偏心2孔板弯曲 孔板边缘尖锐度。下面便一一说明：根据gb2624-81规定，孔板应与节流装置中的直管段对中。实验表明，孔板偏心引起的计量误差一般在2%以内，孔径比β值愈高，偏心率影响愈大，应不用值高的孔板。由于安装或维修不当。使孔板发生弯曲或变形， 导致流量测量误差较大。在法兰取压的孔板上进行测试，孔板弯曲产生的zui大误差约为3.3%。孔板入口边缘磨损变钝不锐或受腐蚀发生缺口，或孔板管道内部的焊缝或计量法兰垫片，都将使实际流量系数增大和差压降低，造成计算气量偏小。
遇到以上的问题怎样提高孔板流量计计量精度的措施：1、消除气流中的脉动流，2、计量装置的设计安装应符台，3、避免人为计量误差。管道中由于气体的流速和压力发生突然变化，造成脉动流，它能引起差压的波动，而节流装置的流量计算公式是以兰孔板的稳定流动为基础的，当测量点有脉动现象时，稳定原理不能成立，从而影响测量精度，产生计量误差。由于影响孔板流量计测量精度的根本原因是节流装置的几何形状和流动动态是否偏离设计标准。因此在使用过程中必须定期做好系统的校检、维护工作，对于实际使用中的压力、温度、流量等工况参数的变化，应进行及时修正。可采用全补偿的流量计算机的积算方案，以减少计量误差，确保计量精度。加强计量管理，提高操作人员技术素质，积极引进吸收*的天然气计量技术。
英文版本：
standard orifice flow meter is a circular perforation plate obtained by mechanical processing. its upstream orifice cylindrical cylinder and plate end vertical, the edge is sharp, pore thick and orifice diameter ratio is relatively small. part of orifice in the measuring tube should be round and the measuring tube coaxial, both ends of the surface plate should always be several factors flat and parallel to the orifice plate flowmeter error: 1 pore plate eccentric 2 hole plate bending plate edge sharpness. the following one one description: according to gb2624-81 regulations, straight pipe orifice plate and throttling device in. experiments show that the measurement error caused by the eccentric orifice plate, generally within 2%, aperture value is higher than the beta, the eccentricity effect is bigger, should not use the value of orifice plate high. due to improper installation or repair. the hole plate bending or deformation, resulting in flow measurement error. tested in the orifice flange taps on the orifice plate bending, the maximum error is about 3.3%. orifice entrance edge wear blunt not sharp or corroded gaps, or orifice pipe inner weld or measure the flange gasket, will make the actual discharge coefficient and pressure to reduce the calculation volume too small, resulting in.
encounter the above problem how to improve the accuracy of orifice flowmeter measures: 1, eliminating the pulsating flow in the flow, design 2, metering device installation should be consistent, to avoid human error of measurement, 3. pipeline by the velocity and pressure of gas caused by the sudden change, pulsatile flow, it can cause differential pressure fluctuation, and the throttling device flow calculation formula is to stabilize the flow blue hole plate based, when the measuring point with pulsation, stable principle can not be established, which affects the measurement accuracy, the measurement error. because the reasons affecting measuring accuracy of orifice flowmeter is geometry and flow dynamic throttling device will deviate from the designed standard. therefore, in the use of the process must be regularly to make the system calibration, maintenance, change to the actual use of the pressure, temperature, flow and other parameters should be revised promptly. integrating scheme uses the full compensation of the flow computer, in order to reduce the measurement error, to ensure that the metering accuracy. strengthen the measurement management, improve the technical quality of operators, and actively introduce foreign advanced technology of natural http://china-211600.com gas measurement.