The　hydraulic　system　often　needs　precise　control　capacity　that　simultaneously　possesses　both　large　and　small　flow　capacity.　So　the　novel　variable　gain　propositional　cartridges　valve　is　designed,　which　could　realize　the　switching　control　of　large　and　small　flow　capacity　by　just　one　hydraulic　component.　The　envelope　valve　is　embedded　in　the　outside　of　the　valve　spool,　valve　spool　and　envelope　valve　are　set　respectively　with　corresponding　valve　port　of　large　and　small　flow,　depending　on　them　to　constitute　the　structure　of　controllable　double　valve　port　and　variable　gain.　The　two　sides’　sensitive　chambers　of　the　envelope　valve　are　controlled　by　the　external　control　valves,　and　the　high　precision　position　control　of　envelope　valve　can　be　realized.　The　controllable　port　is　in　the　large　or　small　flow　working　conditions　depend　on　whether　the　valve　spool　and　the　envelope　valve　are　cooperative　working　or　not.　The　static　model　of　the　novel　variable　gain　propositional　cartridge　valve　is　established,　and　the　pressure　flow　characteristic　is　obtained,　which　indicate　that　variable　gain　in　any　position　can　be　achieved.　The　dynamic　simulation　model　of　the　valve　is　established　by　AMESim,　and　linear　position　control,　switching　at　any　position　and　velocity　are　simulated　respectively,　the　results　show　that　the　control　performance　of　novel　variable　gain　proportional　cartridge　valve　is　outstanding,　stable　switch　at　arbitrary　position　and　speed　can　be　carried　out,　and　the　favorable　linear　variable　gain　output　and　switching　characteristics　are　obtained,　which　can　effectively　improve　the　adaptability　of　the　cartridge　valve.　©　Sila　Science.　All　rights　reserved.