美國力沃LEO]進口杠桿浮球式是利用浮力原理和杠桿原理，通過液位的變化使浮球上升或下降，浮球驅(qū)動著杠桿使得閥瓣離開或接觸閥座達到開啟排水和關(guān)閉阻汽的作用。采用自動排空氣閥，能自動排除不凝結(jié)氣體，非常靈敏，工作質(zhì)量高，使用壽命長。連續(xù)排水，有水即排，zui小過冷度為┃0℃。杠桿浮球式疏水閥采用兩種結(jié)構(gòu)方式┃A：單閥座-杠桿浮球;┃B：雙平衡閥座-杠桿浮球。

單閥座：需要克服介質(zhì)壓力對閥座的作用，閥座的孔徑不能很大，適用于小型設(shè)備、伴熱管線，蒸汽主管等排水小的場合。閥座孔設(shè)計在凝結(jié)水水位以下，自然形成水封，水、汽自然分離，達到無蒸汽泄漏，即便沒有凝結(jié)水采用球型密封的杠桿使得閥瓣緊貼閥座，達到無新鮮蒸汽的泄漏。不受凝結(jié)水量波動和溫度的影響。

雙平衡閥座：該閥利用雙閥孔設(shè)計，介質(zhì)的壓力對兩個閥座作用相等，方向相反，介質(zhì)壓力對閥座作用相抵消，閥芯在開閥時壓力相對減少，從而獲得超大排量。工作時浮球隨閥腔內(nèi)液體位的變化而上下浮動，帶動杠桿打開或關(guān)閉閥座。由于閥座孔在凝結(jié)水水位以下，形成水封，水、汽自然分離，達到無蒸汽泄漏。不受壓力、溫度、冷凝水流量波動的影響。

┃Lever-ball┃float┃trap

The┃lever-ball┃float┃type┃trap┃employs┃the┃buoyancy┃and┃leverage┃principles:┃to┃make┃the┃ball┃float┃ascend┃or┃descend┃by┃the┃change┃in┃the┃liquid┃level┃and┃then┃the┃ball┃float┃drives┃the┃lever┃to┃make┃the┃valve┃disc┃depart┃from┃or┃touch┃the┃valve┃seat┃to┃realize┃drainage┃and┃close┃the┃block┃vapor.┃The┃product┃adopts┃the┃automatic┃air┃exhaust┃to┃automatically┃eliminate┃non-condensing┃air.┃It┃is┃very┃precise┃with┃high┃operating┃quality┃and┃long┃service┃life.┃It┃can┃discharge┃whenever┃there┃is┃any┃water,┃and┃its┃minimum┃subcooled┃temperature┃is┃0℃.┃The┃lever-┃ball┃float┃trap┃adopts┃two┃kinds┃of┃structure┃modes:┃A:┃Single┃valve┃seat-lever┃ball┃float;┃B:┃double┃balanced┃valve┃seat-lever┃ball┃float.┃

Single┃valve┃seat:┃it┃needs┃to┃overcome┃the┃operation┃on┃the┃valve┃seat┃by┃the┃medium┃pressure;┃the┃hole┃caliber┃of┃the┃valve┃seat┃cannot┃be┃too┃large┃and┃is┃applicable┃to┃such┃low┃displacement┃condition┃as┃mini-equipment,┃steam┃tracing┃pipeline┃and┃steam┃main┃pipe.┃The┃hole┃of┃the┃valve┃seat┃is┃designed┃beneath┃the┃water┃level┃of┃the┃condensate┃water┃to┃form┃water┃sealing┃to┃keep┃water┃apart┃from┃vapor,┃so┃as┃to┃prevent┃the┃leakage┃of┃the┃vapor.┃Though┃there┃is┃no┃condensate┃water┃that┃uses┃ball-type┃sealed┃lever┃to┃make┃the┃valve┃clack┃tightly┃adhesion┃to┃the┃valve┃seat,┃it┃can┃prevent┃the┃fresh┃vapor┃from┃leakage.┃Further,┃the┃product┃is┃free┃of┃the┃affect┃of┃the┃fluctuation┃of┃the┃condensate┃water’s┃quantity┃and┃temperature.

The┃double┃balanced┃valve┃seat:┃this┃valve┃is┃designed┃to┃have┃two┃valve┃openings.┃The┃pressure┃of┃the┃medium┃act┃against┃the┃two┃valve┃seats┃equally┃in┃reverse┃direction,┃so┃the┃pressure┃on┃the┃valve┃seat┃is┃offset,┃the┃valve┃core┃assumes┃relatively┃low┃pressure┃when┃the┃valve┃is┃open,┃in┃this┃way┃the┃overlarge┃displacement┃is┃obtained.┃During┃the┃operating┃process,┃the┃ball┃float┃floats┃with┃the┃change┃in┃liquid┃level┃of┃the┃valve┃cavity┃to┃make┃the┃lever┃open┃or┃close┃the┃valve┃seat.┃The┃hole┃of┃the┃valve┃seat┃is┃designed┃beneath┃the┃water┃level┃of┃the┃condensate┃water┃to┃form┃water┃sealing┃to┃keep┃water┃apart┃from┃vapor,┃so┃as┃to┃prevent┃the┃leakage┃of┃the┃vapor.┃Further,┃the┃product┃is┃free┃of┃the┃affect┃caused┃by┃the┃fluctuation┃of┃pressure,┃temperature┃and┃condensate’s┃flow