Research On The Structure And Performance For The Plunger Seal Of 6500HP Fracturing Pump

Shale gas in China are mainly distributed in the mountains,For The complex terrain of the mountains,operating area is narrow.Controlling the number of mining equipment and area is especially important,Using high-power fracturing equipment instead of the small power fracturing equipment can reduce the number of fracturing equipment.Along with the fracturing equipment power increases,the fracturing pump plunger seal is also put forward higher requirements.The plunger seal structure to prevent the fracturing fluid leak,fracturing pump volume efficiency and guarantee the fracturing equipment play an important role during normal operation.This paper uses the finite element simulating the type of 6500 HP fracturing pump plunger seal and the plunger sealing performance.The influence factors of plunger seal performance are considered in the simulation process of plunger seals as well as the state of the nonlinear geometry,materials,and the performance of the plunger seal are analyzed,The seal of the temperature field and thermal stress coupled field are analyzed and studied the born mechanical hysteresis heat and friction heat on the influence of the sealing performance.The seal clearance between plunger and seal are analyzed.Analysis and study the conclusions are as follows:1,Through theoretical analysis and modeling the structure of rubber sealing ring.Using the study of the improvement of the v-shaped sealing ring structure design Through to the nonlinear theory,the structure of the rubber material of the hyperelastic of plunger seal finite element model is established.Carried on the research and analysis,the results show that the v-shaped seal lip and lower lip Angle column close to the Great Wall lateral part of the most prone to failure.In the process of the relative movement between the plunger and seal friction,as a result of the existence of friction,it reduces the service life of piston ring,at the same time of fracturing fluid in fracturing pump working pressure and the friction coefficient between plunger and seal of fracturing pump plunger seal effect has important influence.2,The plunger seal temperature field is analyzed.By using the theory of heat transfer,heat source of piston ring is analyzed.In the process of fracturing pump work,the plunger and seal the relative sliding.Sliding sealing ring in the process of heat source there are two major pieces.The first block is sliding friction between the plunger and seal the heat.The heat is mainly focused on the part of the piston and sealing ring contact,making the seal lip height temperature inside;the second piece is due to the working process of the seal ring,rubber mechanical lag factors to generate heat.Through the structure of "V" can be seen that the lips rubber material is less than the back,mechanical hysteresis occurs mainly in the back of the sealing ring near the center position,in under the action of sliding friction and mechanical lag two factors makes the plunger seal of the local temperature,at the same time due to the fracturing fluid and the rise of temperature of fracturing fluid pressure increase will cause temperature rise of plunger seal.3,Thermal stress coupling analysis was carried out on the seal ring.By putting a seal ring sealing ring in the process of working temperatures rise internal stress increased feedback to the structural analysis of the stress field,the result of the feedback results showed that the environmental temperature is lower.Rubber heat bilges cold shrink cause the loss of the elasticity of the sealing material.With declining seal flexible,it leads to poor sealing effect,untight seal.The leakage quantity to increasing,due to decreased elasticity may seal ring sealing ring and local crack occur.After the occurrence of cracks,prevented sealing ring of the elastic recovery;Caused by high temperature oxidation is also easy to rubber sealing ring,sealing ring aging,deformation.The sealing ring of the tension and elasticity,and hardness will be greatly reduced.4,Plunger seal clearance is modeling.Through the simulation of the plunger sealing ring seal clearance,analysis of gap size,inlet pressure,the correlation between the leakage,and with the help of simulation analysis,we get the results as follows: when the inlet pressure and expanding gap size,the leakage will also increase occur synchronous,and a subtle changes,and even clearance leakage can also cause great changes.