Brand-new CFB boiler furnace outlet non-metal expansion joint

Abstract

The invention discloses a brand-new CFB boiler furnace outlet nonmetal expansion joint. The brand-new CFB boiler furnace outlet nonmetal expansion joint comprises two metal frames which are correspondingly arranged, the outer ends of the metal frames are provided with combined retaining rings which are fixedly connected into a whole through bolt assemblies, inner protection plates are arranged on the inner side faces of the two metal frames, a heat insulation sleeve is embedded between the combined retaining rings and a front cushion block, and a sealing ring A is arranged; a flow guide device is installed on the end face of a straight plate which is quarter turn and extends inwards at the outer end of a transverse plate of each inner protection plate, fire-resistant and wear-resistant materials are laid on the inner rings of the metal frame I and the flow guide device in an overall covering mode, the fire-resistant and wear-resistant materials are independently laid on the inner ring of the metal frame II, a high-temperature medium flow channel is formed in the middle, and dust-proof pads are mounted in the gap between the integral fire-resistant and wear-resistant materials and the independently laid fire-resistant and wear-resistant materials. According to the brand-new CFB boiler furnace outlet nonmetal expansion joint, expansion in the three-dimensional direction is met, meanwhile, effective measures are taken to prevent flue gas from flowing back, a heat preservation layer and skin are prevented from being burnt out, the potential safety hazards such as tension fracture, burning loss and ash blowing of the nonmetal expansion joint of the furnace-separator inlet of a large CFB boiler are avoided, and the service life of the expansion joint is prolonged.

Description

technical field [0001] The invention relates to the technical field of thermoelectric facilities, in particular to a brand-new non-metallic expansion joint at the furnace outlet of a CFB boiler. Background technique [0002] The CFB boiler body is divided into three independent suspension parts and support parts: furnace, separator and tail shaft. Expansion joints are used to connect and seal the parts. The expansion joint is a key part of the circulating fluidized bed boiler, and its working quality directly affects the safe operation of the boiler. The characteristics and overall layout of the CFB boiler require non-metal expansion energy-saving to effectively absorb the expansion, no leakage, no burning loss. [0003] The three-dimensional expansion of the CFB boiler in the high-temperature area and the three-dimensionally expanded furnace-separator inlet area is absorbed by non-metallic expansion joints. This area is a dense-phase area, and the working environment is h...

AI Technical Summary

Problems solved by technology

[0006] 1) The air leakage of the boiler increases. In order to maintain the negative pressure at the separator inlet (furnace outlet), the induced draft fan needs to increase its output, resulting in an increase in plant power consumption; if the induced draft fan margin is insufficient to compensate for the pressure change caused by the air leakage, it will cause boiler MFT action

[0007] 2) During the long-term operation of the CFB boiler, the furnace pressure will fluctuate within a certain range. If the expansion joint breaks, the flue gas of the boiler will leak out, causing the deterioration of the operating environment of the power plant, which is not conducive to civilized production

[0008] 3) After the expansion joint is broken, the flue gas temperature at the furnace outlet will drop, which is not conducive to the heat transfer of the flue gas at the tail. In severe cases, it will cause insufficient heat absorption on the heating surface at the tail, reduce the steam temperature of the superheater and reheater, and affect the performance of the boiler

Images