Spring tube pressure gauge repair and adjustment techniques
practice. Maintenance and Adjustment Techniques for Experienced Spring Tube Pressure Gauge The pressure gauge commonly used in the industry is a Y-type spring tube pressure gauge, which is made by the principle that the spring tube is deformed by the pressure of the measured medium. Suitable for measuring the pressure of liquids, vapors and gaseous media. Some of the experiences and techniques summarized in the calibration and maintenance of pressure gauges are shared with you.
1 The reason for the excessive tapping displacement and the adjustment of the axial gap of the active part of the transmission mechanism are too large, and the balance of the hairspring is too small. Adjust the axial clearance to make it smaller.
The hairspring is scattered and the tension is uneven. Straighten or replace the hairspring to make the tension even.
The pointer is not securely installed and the transmission mechanism is partially worn. Fix the pointer and repair the wear of the transmission mechanism.
Loosen the pointer rivet to replace the pointer or secure the pointer.
The adjustment is uneven and the adjustment is fast and slow. Turn the movement to reduce the angle of the sector gear and the tie rod.
Fast before and after. Turn the movement to increase the angle of the sector gear and the lever.
Hurry and slow. The movement is fixed and the transmission mechanism is well matched.
3 When the pressure is applied to the maximum scale, the pointer does not refer to the adjustment of the maximum scale to adjust the pin position, so that the pointer points to the position of the maximum scale.
After the pressure is released, the pointer should be reset to zero position. If there is deviation, the zero position can be reset.
Repeat the above steps so that the pointer can indicate the zero position and the maximum scale point.
4 adjustment of the intermediate scale During the pressure check process, if the error and the scale are in a proportional relationship, the pin can be fine-tuned: the positive error moves outward, and the negative error moves inward; if the first part (or the latter part) of the scale passes the error, The rest is unqualified and is proportional to the scale. The angle between the tie rod and the sector gear can be adjusted. When the force is one-half of the scale, the angle is generally 90°. You can adjust the angle by changing the length of the lever.
If the pressure gauge has a large variation, it is generally because the transmission mechanism has large friction or loose contact, and the unqualified part can be inspected and eliminated.
Gujing Town Gujing Distillery Co., Ltd. Energy Measurement Division Yang Qizhen|Editor: Xue Minjun selects the type of regulating valve. The regulating valve is the executive part of the control system. For (2) the production often works in the small flow rate valve positioner) Regulating valve; process conditions for the fluid to be controlled, the regulating valve can be regarded as a controllable change resistance in the controlled system. When the controlled parameter deviates from the set value, according to the control system adjusts the regular output value, the opening degree of the regulating valve is changed accordingly, thereby changing the flow rate of the fluid, thereby overcoming the influence of the disturbance on the system and realizing the purpose of automatic adjustment.
The calculation of the flow capacity of the regulating valve directly affects the quality of the adjustment. Since there is a lot of information on the calculation of the flow capacity of the regulating valve, and the calculation of the flow capacity of the regulating valve is not as strict as the calculation of the throttle device, the focus of this paper is to summarize the precautions for selecting the type of regulating valve.
Since the parameters and production conditions of the medium in the production process are not as ideal as when calculating the regulating valve (for example, when the on-site gas supply pressure is minimum, the maximum flow required for production can be ensured; when the on-site gas supply pressure is maximum, To ensure that the minimum flow required for production is stable, then an equal percentage control valve with a considerable amount of flow capacity should be selected.
If the S value is small, the flow characteristic curve is easy to float, and an equal percentage adjustment valve should be used.
In the production, the flow rate is required to be relatively stable, and when working in a large flow range or when the S value of the regulating valve is relatively large, a linear valve should be selected.
Process requirements A single seat valve should be selected when the regulator valve must be closed.
The process requires a double seat valve when the regulator valve is not tightly closed or the regulator valve closes to create a large pressure differential.
Process requirements In the event of an accident, the original valve position must be maintained. An electric valve or a pneumatic valve with a lock should be selected.
Process requirements In the event of an accident, the maximum passage must be maintained with a gas shut-off regulator.
Process requirements In the event of an accident, the air-opening regulator valve should be selected.
The process conditions require that the control valve has a large starting force. The electrified/gas valve positioner should be used (or the control valve with optional electric/gas converter that has little starting force for the regulating valve).
(1 (1) The process requires important regulating valves, and the regulating valve with position feedback and switching stroke should be selected.
The medium to be tuned is an explosion-proof gas or a toxic gas. The general medium is available as a cast steel housing regulating valve.
When the medium to be conditioned is corrosive, the control valve with anti-corrosion protection lining should be selected.
The medium to be conditioned is a high temperature (such as steam) to choose a heat-resistant regulating valve.
(14) The medium to be tuned is of high viscosity, and the angle control valve should be selected when there is suspended matter.
This article is based on the practical experience summarized in the Taigang process. Due to the limited level, the inappropriate expression and the summary is not perfect, I hope that the readers will understand and correct.
Lin Hao, Shanxi Taiyuan Iron and Steel (Group) Co., Ltd.
Fujitec Escalator Spare Parts, Fujitec Escalator Parts
Fujitec has been devoted to manufacturing high-quality, reliable escalators in harmony with municipal scenery and buildings. It designs and develops the quick, quiet, smooth, safe, and reliable GS-NX series of escalators with complete functions, pursues the individualized escalator production and realizes the optimum locomotion system.
Fujitec Escalator Spare Parts,Fujitec Escalator Parts,Fujitec Escalator Contactor Spare Parts
CEP Elevator Products ( China ) Co., Ltd. , https://www.zjelevatortravelingcable.com