Working condition
| Pressure Rating | CLASS 150 to CLASS 900 (PN 10 to PN 150) |
| Nominal Diameter | NPS 1.5 to NPS 24(DN 40 to DN 600) |
| Internal Leakage Standard | ANSI FCI 70-2, CLASS VI or higher |
| Applicable Media | Liquid phase, gas phase, severe condition with solid medium; |
| Temperature Range | ≤750°C |
| Fireproof & Anti-Static Design | Support |
| Operation Method | Pneumatic |
Pain Points and Proposal
1. External Leakage:
① Temperature alternation causes external leakage of the valve, which is prone to safety accidents.
② Packing failure occurs in high-temperature environments, leading to external leakage.
2. Internal Leakage:
① Metal galling and heat accumulation on hard alloy sealing surfaces easily occur under high temperatures which causes scratches between valve disc and seat.
② In high-temperature environments, the metal structural adhesive fails, causing the valve seat to fall off and leading to internal leakage.
3.Jamming:
① Sealing surface damage due to metal galling and thermal buildup (as in 2①) causes.
② During temperature cycling and thermal shock, the valve stem components get biting, preventing the valve from opening and closing normally.
1.Using high-temperature coating FS60, its hardness is HRC65 - 74. It does not cause metal to metal biting under high-temperature working conditions, and has properties of corrosion resistance, thermal shock resistance and erosion resistance, effectively solving problems such as wear and falling off of the sealing surface under high-temperature working conditions.
2.Self-rotating trim, which can self-milling the sealing surface to compensate for wear.
3.The high rigidity coefficient enables high reverse pressure difference, preventing solid materials from entering the sealing surface. The rigidity coefficient is basically independent of temperature. Even if solid materials enter the Belleville spring, it will not affect the use of the valve, effectively solving the compensation of sealing force caused by high-temperature alternation.
4.Disc spring bearing packing design, adopting multiple packing design. The live- loaded design provides continuous pre-tightening force for the packing, effectively compensating for temperature and pressure fluctuations as well as packing wear, so as to prevent stem leakage.
5.Extended stem design with efficient heat conduction, controlling the packing temperature below 300℃.
6.Reasonable clearance control ensures flexible rotation between the stem and the bushing, preventing the valve from jamming under high-temperature working conditions. It is necessary to accurately determine the clearance between various parts by considering the thermal expansion coefficient, stress and service temperature of the materials.
7. The middle flange sealing combined with Belleville spring compensation can effectively solve the middle channel leakage caused by high and low temperature alternation of the valve.
Reference