NB/T47017 pressure vessel sight glass combines multiple styles such as HGJ51-502-1986 pressure vessel sight glass, HG/T21575-1994 light sight glass, and HG/T21505-1992 combination sight glass, creating one style. And significant improvements have been made, including the addition of DN200 mirror specifications, increased usage pressure for some mirrors, eliminated mirror flushing holes, adopted flushing devices according to foreign standards, increased mirror specifications with spotlights, and increased requirements for mirror labeling and transportation packaging. Our company's mirrors are strictly processed according to the logo drawings, and can also be customized according to customer requirements;

1、 Main technical parameters of NB/T47017 pressure vessel sight glass:
1. Shell material: Carbon steel WCB, stainless steel 304, 321, 316, 316L;
2. Window materials: tempered glass, tempered borosilicate glass, quartz glass;
3. Sealing material: nitrile rubber, polytetrafluoroethylene;
4. Work pressure: ≤ two point fiveMPaWorking temperature: 0~200℃.

2、 Selection of NB/T47017 Mirrors:
1. This sight glass is a product used to observe changes in media inside industrial equipment containers. The operator adjusts or controls the filling amount based on the displayed situation to ensure that the medium in the container is always within the normal range. Liquefied gas storage tanks, tank trucks, gas-liquid phaseReactors, reactors, and other containers need to be equipped with sight glasses to prevent accidents caused by overloading or imbalances in material reactions caused by excessive feeding;
2. Selection environment: For liquefied gas pressure vessels that are flammable, explosive, and highly toxic, high-temperature and high-pressure small-diameter container sight glasses should be used, and protective devices should be installed to prevent leakage. Low pressure vessels can be equipped with low-pressure sight glasses, and larger sizes can be chosen for the diameter. Containers used outdoors in cold regions, or due to the large difference between the medium temperature and the ambient temperature, should use window materials with high sudden temperature changes. If the light is insufficient, a container sight glass with a lighting device should be selected, and the explosion-proof level should be selected according to the on-site situation.

IIINB/T47017 Pressure VesselsMirror selection instructions:

4、 Installation and maintenance of NB/T47017 pressure vessel sight glass:
1. The mirror should be welded to the part that needs to be observed; Mirror installation, welding flange must be clean and undamaged, operated by professional personnel; The clamping flange should be cleaned and secured with appropriate sealing gaskets;
2. The height should be convenient for the operator to observe, and there should be no components inside that obstruct the line of sight;
3. Avoid welding seams and other components. Working temperature: 0 ℃ -180 ℃;
4. Lens installation, ensure that the mirror base is flat and smooth, the sealing gasket between the lens and the mirror base is installed flat, the sealing gasket is not damaged and does not stick to grease. Before tightening the screws, ensure that the mirror base and cover are installed correctly, and then slowly tighten the screws diagonally;
5. The mirror device with hinged or threaded connection should ensure that the sealing gasket is installed properly before operation. If necessary, the bolts can be re tightened. Ensure that the sealing gasket between the sight hole and the mirror hole is installed correctly, the connecting flange is not damaged, and adjust the connecting screws. Not only should the accessories connected to the pressure vessel sight glass lens be well sealed, but also the sealing between the pressure vessel sight glass and the welding flange should be good. And ensure that the pressure inside the container does not exceed the rated pressure;
6. After installation, there should be no additional pressure on the mirror, otherwise it will cause uneven force on the mirror, leading to the breakage of the mirror glass.

5、 Ordering instructions:
Please specify detailed parameters such as product name, nominal diameter, pressure rating, material, flange standard, etc. when placing an order. The above product parameters are for reference only. Our company can order processing according to user requirements. Please feel free to call or write to us.