Led tube is a kind of differential pressure transform into dc specification signal remote transmission pressure measurement instruments, widely used in industrial production and scientific research, is to obtain, disposal, transfer all kinds of information of hardware. Follow the progress of automation level, the size of its use is more and more widely, the questions encountered in producing more and more, make analysis of the following problems bring pressure pipe: ( 1) Pressure pipe leakage: for differential pressure transmitter contact, cut-off valve accessories, such as walk that funnelled increase, increases protection work. Therefore, to reasonably well lead pressure pipe corrosion and reduce pressure tube present trachoma; Lead the pressure pipe outlet to tighten the screw to prevent loosening. ( 2) Pressure tube obstruction: produced in practice to use protection, because the discharge time medium dirty, maybe with particles, powder and other reasons, time is long, some still can cure, the pressure tube obstruction, make the measurement from otherwise normal operations. Therefore, in order to ensure the normal operation in the transmitter, regularly to the pressure pipe managed to unblock. ( 3) Lead pressure pipe effusion; As the gas flow in a pressure pipe pressure to wrong or equipment is not in conformity with the requirements, often forming pressure pipe internal surface accumulated liquid. This kind of appearance, often causing measure banning, if in the case of transmitter range is small, and will form the transmitter output of some moved. Based has pointed out the correct pressure pipe equipment should be with a lower level of not less than the slope of 1:12, height difference between measurement points and equipment, pressure points should be measured equipments with wall straight. In order to make the measurement more, can set the number of pressure head, all join together into a pressure equalizing tube, repass lead pressure pipe derivation, pressure in the tube of zui settle with lower water drain valve.