A kind of high-pressure mechanical seal of on seal face, slotting
Technical field
The present invention relates to the mechanical seal device of fluid machinery, refer in particular to a kind of high-pressure mechanical seal of on seal face, slotting, particularly the high-pressure mechanical seal device that enters the mouth and use with pumps such as high pressure inlet water lifting pumps, high-temperature high-pressure boiler feed water pumps for the chemical industry recycle pump of high pressure, reverse osmosis seawater desalting.
Background technique
In the fluid machinery machinery of rotations such as centrifugal pump, for preventing to have the dielectric leakage that is transferred of certain pressure and temperature, mechanical seal is usual means.Only need be sealed into mouth pressure in centrifugal pump, usually, the inlet pressure of centrifugal pump can be too not high, and common mechanical seal can meet the demands.But always is difficult problem for the chemical industry recycle pump of high pressure, reverse osmosis seawater desalting with high pressure inlet water lifting pumps, high-temperature high-pressure boiler feed water pump etc., sealing technique for inlet, and the normal way that adopts has series multistage sealing, full liquid film mechanical sealing.
The series multistage sealing configuration is too complicated, and axial dimension strengthens.
Chinese invention patent application 88109152.9 disclosed a kind of full liquid film mechanical sealing apparatus, this patent application be: on the rotating ring of traditional mechanical seal and stationary ring sealing surface, annular dynamic pressure generation conduit is set, be filled with liquid refrigerant in the conduit, when machinery turns round, along with the rotating speed of rotary packing ring raises gradually, liquid refrigerant pressure in the conduit also constantly raises, and spreads between stationary seal ring and two seal faces of rotary packing ring, forms the liquid film with certain pressure.Liquid film phase transformation diameter problem between mechanical seal end surface is not considered in visible this patent application from disclosed file, and when liquid film phase transformation diameter during near the end face outer rim, seal face is difficult to form effective liquid film; Abrasive end face is under the condition of boundary lubrication works, and its PV value allowable is very low, is reflected in the actual using process, is exactly seal face wearing and tearing or scaling loss.And too small when the phase transformation radius, during less than end face inner edge radius, be full liquid film seal, be to be full of one deck liquid film between end face, characteristics are that friction factor is low, leak fluid is a liquid, but leakage rate is bigger.
Summary of the invention
The purpose of this invention is to provide a kind of high-pressure mechanical seal of on seal face, slotting, comprise the dynamic and static ring of sealing, it is characterized in that: fluting distributes along rotary packing ring or stationary seal ring end face phase cylindrical, fluting quantity, groove depth are decided by sealing load, medium temperature situation, in general several 3<n<18 of slotting, its degree of depth h, 0<h<b, b are ring body thickness.Consider the size of phase transformation diameter, should make the phase transformation diameter, be beneficial to form liquid film between end face, do not have too big leakage simultaneously again as far as possible near the end face inner edge.By on sealing surface, driving dynamic trough, will form a relative high-pressure area on the seal face.The pressure distribution of this liquid film is to be linear decrease up to entering dynamic trough from the seal face outer rim.Medium hydrodynamic pressure through dynamic trough the time remains unchanged, and then is linear decrease up to the sealing surface inner edge surface from dynamic trough.It can make mechanical seal end surface produce dynamic pressure effect, strengthens the formation of end face liquid film, improves the lubricating condition of seal face, suppresses the phase transformation of liquid film.Slot and preferably evenly distribute along seal ring end face phase cylindrical, the shape of groove can be the compound groove of semicircle, rectangle, crescent shape, triangle, rhombus or several shapes.
The present invention is applicable to all liq mechanical seal.Advantage is: for mechanical seal provides effective dynamic pressure effect, improve the ability of bearing high-pressure liquid of mechanical seal itself, increased the reliability and the working life of sealing.
Description of drawings
Fig. 1 is specific embodiments of the invention sectional drawing Fig. 2 semi-circular groove schematic representation of the present invention
Fig. 3 rectangle groove schematic representation of the present invention Fig. 4 crescent-shaped slot schematic representation of the present invention
Fig. 5 vee gutter schematic representation of the present invention Fig. 6 rhombus groove of the present invention schematic representation
Fig. 7 compound groove schematic representation of the present invention
Among Fig. 1,1. running shaft 2. sealing axle sleeves 3. rotating ring retainer assemblies 4. seal ring of moving ring 5 backup rings 6. rotary packing rings 7. stationary seal rings 8. stationary ring seal rings 9. seal end plate assemblies
Embodiment
The present invention as the high pressure water feeding pump for boiler shaft end seal as shown in Figure 1, sealing axle sleeve 2 is fixed on the running shaft 1, rotary packing ring 6 is contained on the sealing axle sleeve 2 by rotating ring retainer assembly 3, the controlling mechanism that includes rotary packing ring 6 in the rotating ring retainer assembly 3, has excellent contact with the sealing surface that guarantees rotary packing ring 6 and stationary seal ring 7, guarantee not have leakage by seal ring of moving ring 4 between rotary packing ring 6 and the axle sleeve 2, backup ring 5 is the sealing effects that are used for guaranteeing seal ring of moving ring 4, stationary seal ring 7 is fixed on the seal end plate assembly 9, guarantee not have leakage between stationary seal ring 7 and the seal end plate assembly 9 by stationary ring seal ring 8, on rotary packing ring 6, have semicircle conduit (8) as shown in Figure 2, high temperature high pressure liquid flows to will form a relative high-pressure area on the seal face, the pressure distribution of this liquid film is to be linear decrease up to entering dynamic trough from the seal face outer rim.Medium hydrodynamic pressure through dynamic trough the time remains unchanged, and then is linear decrease up to the sealing surface inner edge surface from dynamic trough.It can make mechanical seal end surface produce dynamic pressure effect, strengthens the formation of end face liquid film, improves the lubricating condition of seal face, suppresses the phase transformation of liquid film, and the existence of stablizing liquid film can be played seal action and can prevent to have between the seal face excessive mechanical friction again.All be higher than prior art far away through indexs such as working life, power consumption, amount of leakage, successfully be applied in the industrial production.