JP2004132597A

JP2004132597A - Pipe cleaning device and pipe cleaning method

Info

Publication number: JP2004132597A
Application number: JP2002296875A
Authority: JP
Inventors: Hiroaki Tsuboe; 坪江　宏明; Susumu Nakayama; 中山　進; Hiroshi Yasuda; 安田　弘; Kensaku Kokuni; 小国　研作; Koji Naito; 内藤　宏治
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Priority date: 2002-10-10
Filing date: 2002-10-10
Publication date: 2004-04-30

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pipe cleaning device and pipe cleaning method for a refrigeration cycle improved in the reliablity of a refrigeration unit by reducing the quantity of refrigerator oil left in an existing pipe to suppress the deterioration of the refrigerator oil sealed in an outdoor machine to be newly connected. <P>SOLUTION: This pipe cleaning device 40a for refrigeration cycle performs the cleaning of the refrigeration unit having a refrigeration cycle connected by a liquid connecting pipe 65 and a gas connecting pipe 68 by circulating a refrigerant in the liquid connecting pipe 65 and gas connecting pipe 68. The pipe cleaning device 40a has a vapor compression refrigeration cycle formed by successively connecting a refrigerant compressor 1a, an air heat exchanger 2, a pressure reducing device 7 and an evaporator 4b, and a foreign matter separation device 11 arranged between the evaporator 4b and the refrigerant compressor 1a. The cleaning refrigerant condensed by the air heat exchanger 2 is circulated in the liquid connecting pipe 65 and gas connecting pipe 68. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、冷凍サイクルを利用した空気調和機や冷凍機を含む冷凍装置に使用する接続配管を洗浄する配管洗浄装置及び配管洗浄方法に関する。
【０００２】
【従来の技術】
空気調和機及び冷凍機を含む冷凍装置の配管の洗浄方法として、既設の冷凍装置とは別の冷凍サイクルにより、冷凍装置に使用している冷媒と同じ冷媒を用いて配管を洗浄し、配管内に残った配管の切断時に生じた切り粉やバリ取りかすや配管の溶接作業で配管内表面に生じた酸化皮膜（酸化銅）などの塵や、配管内に残留した水分を取り除くために、洗浄冷媒中に混入した前記塵や水分を、配管洗浄用循環ポンプと阻止弁の間の接続パイプに配設したフィルターにより取り除くことが知られ、例えば特開２００１−１８３０３５号公報に記載されている。
【特許文献１】
特開２００１−１８３０３５号公報
【０００３】
【発明が解決しようとする課題】
上記従来技術においては、洗浄冷媒中に冷凍機油が溶解した際に、洗浄冷媒と冷凍機油とを分離しておらず、既設配管内に残留した冷凍機油を取り除くには、新品の洗浄冷媒を別途用意する必要がある。室内機が複数台接続するマルチ式の空気調和機や配管長が長いシステムであって、既設配管内に残留する冷凍機油の量が多い場合では、配管内の洗浄状態によっては１００ｋｇ以上の新品の洗浄冷媒が必要とされる。
【０００４】
本発明の目的は、既設配管内に残留する冷凍機油の量を低減して新規に接続する室外機に封入された冷凍機油の劣化を抑制し、冷凍装置の信頼性を向上した冷凍サイクルの配管洗浄装置及び配管洗浄方法を提供することにある。
【０００５】
【課題を解決するための手段】
上記課題を解決するために、本発明は、液接続配管及びガス接続配管で接続された冷凍サイクルを有する冷凍装置に対して、冷媒を前記液接続配管及びガス接続配管内に循環させて洗浄を行う冷凍サイクルの配管洗浄装置において、前記配管洗浄装置は、冷媒圧縮機、空気熱交換器、減圧装置、蒸発器が順次連結されて蒸気圧縮冷凍サイクルが構成され、前記蒸発器と前記冷媒圧縮機との間に異物分離装置が配置され、前記空気熱交換器によって凝縮された洗浄冷媒を前記液接続配管及びガス接続配管内に循環させるものである。
【０００６】
また、上記のものにおいて、前記冷媒圧縮機の吐出側に油分離器を配置し、該油分離器で分離した冷凍機油を前記冷媒圧縮機の吸入側に導出することが望ましい。
さらに、上記のものにおいて、空気熱交換器により凝縮した洗浄冷媒の一部は液バイパス回路用減圧装置を介して、前記冷媒圧縮機の吸入側に導入されることが望ましい。
さらに、前記空気熱交換器で凝縮された冷媒と、前記液接続配管及びガス接続配管を通って前記減圧装置により減圧された後の冷媒との間で熱交換を行う液−ガス熱交換器を設けたことが望ましい。
【０００７】
さらに、本発明は、液接続配管及びガス接続配管で接続された冷凍サイクルを有する冷凍装置に対して、冷媒を前記液接続配管及びガス接続配管内に循環させて洗浄を行う冷凍サイクルの配管洗浄方法であって、前記液接続配管及びガス接続配管に、冷媒圧縮機、空気熱交換器、減圧装置、蒸発器が順次連結され、前記蒸発器と前記冷媒圧縮機との間に異物分離装置が配置された配管洗浄装置及び該配管洗浄装置に回収ボンベを接続し、前記冷媒圧縮機より吐出した高温高圧冷媒を前記空気熱交換器で凝縮し前記回収ボンベ内に導入する冷媒回収運転を行い、回収された液冷媒を前記液接続配管及びガス接続配管に流出して循環させ、前記配管洗浄装置内に流入し、流入した冷媒を前記減圧装置で減圧して前記蒸発器で蒸発させ、前記異物分離装置を介して前記冷媒圧縮機へ吸入させる配管洗浄運転を行うものである。
【０００８】
【発明の実施の形態】
以下本発明の実施の形態について図を用いて説明する。
図１は、一実施の形態によるサイクル系統図を示し、図５は図１のものを用いて配管洗浄運転を行うときのサイクル系統図、同じく図７は冷媒回収運転時のサイクル系統図を示している。
【０００９】
冷凍装置を運転した後に、配管には冷媒圧縮機から冷媒とともに吐出した冷凍機油が残留する。残留した冷凍機油は長期間立つと劣化し、冷凍機油の全酸価や過酸価物価が上昇する。長期間冷凍装置を運転した後の既設の配管を流用して室外機のみまたは室外機及び室内機を新品に交換した場合、既設の配管内に残留した劣化油の影響により、新品の室外機に封入されていた冷凍機油も劣化が加速され、冷媒圧縮機の摺動部の化学磨耗が促進される。さらには銅メッキ現象の発生、モータ材の絶縁不良などにより冷媒圧縮機が故障し、本来の製品寿命以下となる恐れもある。
さらに、長期間運転した冷凍装置に封入された冷媒がＨＣＦＣ−２２であって、新規に接続する室外機に封入された冷媒がＨＦＣ系冷媒（例えばＲ−４１０Ａ、Ｒ−４０７Ｃ）の場合、既設配管に残留するＨＣＦＣ−２２用の冷凍機油は、ＨＦＣ系冷媒には溶解しないのでキャピラリ等で詰まり、より信頼性を低下する。
【００１０】
図１の配管洗浄装置４０ａは、冷媒圧縮機１ａ内の冷凍機油量を、冷媒圧縮機１ａの外部から見ることができるように、冷媒圧縮機１ａに油面計１０を配置している。冷媒圧縮機１ａは冷媒とともに冷媒圧縮機１ａ内の冷凍機油も吐出する。そのため冷媒圧縮機１ａ内の冷凍機油は、冷媒圧縮機１ａの吸入側より供給されない限り、無くなるので、冷媒圧縮機１ａの摺動部に給油できなくなり、摺動部が焼付き、冷媒圧縮機１ａが故障する。配管洗浄装置４０ａでは、冷媒圧縮機１ａの吸入側に異物分離装置８を配置し、異物分離装置８で冷凍機油を分離するので、冷媒圧縮機１ａには冷凍機油が戻ってこない。そこで、油面計１０から冷媒圧縮機１ａ内の冷凍機油量を確認し、冷凍機油が規定量以下となったら給油口２４より冷凍機油を追加する。
【００１１】
図５ないし図８を参照して一実施の形態による配管洗浄装置について説明する。
冷媒としてＣＦＣやＨＣＦＣ系冷媒を充填した既設の室外機４１、既設の室内機４２ａ、４２ｂとそれぞれを接続する液接続配管６５及びガス接続配管６８により構成した冷凍装置内の冷媒を回収した後、配管洗浄装置４０ａを接続する。室外機４１内に冷媒を回収するポンプダウン運転を実施した後、あるいは、実施することなく、液接続配管６５及びガス接続配管６８及び室内機４２ａ、４２ｂの冷媒を空の回収ボンベ５０に回収する。図８は、空の回収ボンベ５０内に冷媒を回収する際の冷凍装置と配管洗浄装置との接続状態を示し、室外機４１の液阻止弁６４あるいはガス阻止弁６９に併設したサービス口６４１あるいは６９１と配管洗浄装置４０ａの阻止弁６とを接続配管５６ａを用いて接続する（図８では、一例としてガス阻止弁６９側のサービス口６９１と配管洗浄装置４０ａの阻止弁６とを接続している）。
【００１２】
回収ボンベ５０は、予め回収ボンベ５０内の空気を除くため真空引きを実施し、真空引きした回収ボンベ５０のガス側接続口５１と配管洗浄装置４０ａの接続口３１とを、回収ボンベ５０の液側接続口５２と配管洗浄装置４０ａの接続口２３（３３）とを、チャージホース５３、５４を用いて接続する。
【００１３】
次に、配管洗浄装置４０ａの冷媒回収運転を行い、この時の冷媒の流れについて説明する。
配管洗浄装置４０ａの阻止弁５は閉じた状態で、阻止弁６は開いた状態で、電磁弁２０は閉じた状態で運転する。冷媒圧縮機１ａより吐出した高温高圧冷媒は、空気熱交換器２で凝縮し、高圧の液冷媒または気液二相冷媒となる。冷媒圧縮機１ａが運転した後、電磁弁２３を開けることで高圧の液冷媒または気液二相冷媒は回収ボンベ５０内に導入される。また、冷媒圧縮機１ａの吸入側は低圧となることから、既設の冷凍装置内の冷媒はサービス口６９１、接続配管５６ａ、阻止弁６を介して配管洗浄装置４０ａ内に導入される。
【００１４】
冷媒回収運転の時間を短縮するために、配管洗浄装置４０ａの電磁弁２１を開け、回収ボンベ５０のガス側接続口５１から、回収ボンベ５０内のガス相を配管洗浄装置４０ａ内に回収してもよい。
冷媒回収運転のとき既設の室内機４２ａ、４２ｂの構成部品である減圧装置７１ａ、７１ｂは全開の状態とする。もし減圧装置７１ａ、７１ｂを全開の状態に設定できないときは、サービス口６９１のみならず、サービス口６４１からも冷媒を回収する。
【００１５】
以上のような冷媒回収運転を実施した後、既設の液接続配管６５及びガス接続配管６８の洗浄運転を実施する。この配管洗浄運転時の配管洗浄装置４０ａと冷媒回収後の既設冷凍装置との接続方法について説明する。
冷媒回収運転の際、室外機４１内に冷媒を回収するポンプダウン運転を実施した場合は液阻止弁６４及びガス阻止弁６９を全閉とした後、液接続配管６５及びガス接続配管６８と液阻止弁６４及びガス阻止弁６９とを分離する。分離した液接続配管６５及びガス接続配管６８とは、接続配管５５、５６を介して配管洗浄装置４０ａの阻止弁５、６に接続する。室内機４２ａ、４２ｂの減圧装置７１ａ、７１ｂを全開の状態にすることが可能ならば、室内機４２ａ、４２ｂを液接続配管６５及びガス接続配管６８に接続した状態で、減圧装置７１ａ、７１ｂを全開の状態に設定できないときは、室内機４２ａ、４２ｂを液接続配管６５及びガス接続配管６８から取り外し、液接続配管６５及びガス接続配管６８を開閉弁６７ａ、６７ｂを備えたバイパス枝管６６ａ、６６ｂを用いて接続する。この状態では、洗浄すべき液接続配管６５及びガス接続配管６８には洗浄冷媒が封入されていない。配管洗浄運転を実施するには、洗浄冷媒を液接続配管６５及びガス接続配管６８に封入したのち実施する。洗浄冷媒の封入方法及び配管洗浄運転時における洗浄冷媒の流れについて図８を参照して説明する。
【００１６】
洗浄冷媒としては洗浄すべき液接続配管６５及びガス接続配管６８内に残留する冷凍装置で使用していた冷凍機油と相溶性を有する冷媒を選定する。冷凍装置で使用していた冷媒と冷凍機油の間に相溶性があるならば、洗浄冷媒として冷凍装置で使用していた冷媒を用いても良い。
室外機４１内に冷媒を回収するポンプダウン運転を実施せず、冷凍装置内に冷媒を全て回収ボンベ５０内に回収した場合は、図８の通り、冷媒を回収済みの回収ボンベ５０内のガス側接続口５１と配管洗浄装置４０ａの接続口３１とを、回収ボンベ５０の液側接続口５２と配管洗浄装置４０ａの接続口２３（３３）とを、チャージホース５３、５４を用いて接続する。
【００１７】
洗浄運転前に、液接続配管６５及びガス接続配管６８内は真空引きを実施する。配管洗浄装置４０ａの阻止弁５及び阻止弁６は開いた状態で、電磁弁２１は閉じた状態で運転する。この状態で電磁弁２３を開けると、回収ボンベ５０中の冷媒は液接続配管６５及びガス接続配管６８内及び配管洗浄装置４０ａ内に流入する。その後冷媒圧縮機１ａを始動し、電磁弁２０を開けることで、冷媒圧縮機１ａより吐出した高圧の冷媒が回収ボンベ５０のガス側接続口５１より導入され、回収ボンベ５０内の圧力が配管洗浄装置４０ａの接続口２３（３３）の圧力よりも高くなり、回収ボンベ５０内の液冷媒は全て液接続配管６５及びガス接続配管６８内及び配管洗浄装置４０ａ内に流出する。
【００１８】
冷媒圧縮機１ａより吐出された高温高圧冷媒は空気熱交換器２で凝縮され、高圧の液冷媒または気液二相冷媒となり液−ガス熱交換器４（プレート熱交換器、または２重管熱交換器）に流入する。そして、冷媒は液−ガス熱交換器４で熱交換された後、接続配管５５を介して、洗浄すべき液接続配管６５及びガス接続配管６８内を循環し、液接続配管６５及びガス接続配管６８内に残留する異物（主として冷凍装置で使用していた冷凍機油）を洗浄冷媒中に溶解した後、接続配管５６を介して、阻止弁６より配管洗浄装置４０ａ内に流入する。その後、洗浄冷媒は減圧装置７により減圧され、液−ガス熱交換器４の蒸発側４ｂで蒸発しガス単相となる。
【００１９】
ガス単相の洗浄冷媒と洗浄冷媒中に溶解していた異物は、異物分離装置８に導入され、ガス単相の洗浄冷媒の密度よりも重い異物は、重力により異物分離装置８の下方に沈殿（１１）し、洗浄冷媒から分離される。異物の混入していないガス単相の洗浄冷媒は冷媒圧縮機１ａの吸入側へ導出される。
【００２０】
以上のように洗浄すべき液接続配管６５及びガス接続配管６８内には、絶えず異物の混入していない洗浄能力の高い洗浄冷媒が循環するので、配管洗浄装置４０ａの洗浄能力を高い水準で維持することが可能となる。また、冷媒圧縮機１ａに供給される冷媒は、異物を分離した後の冷媒であるので、配管洗浄装置４０ａに封入した冷凍機油と異物とが混合することがないので、信頼性を向上できる。
液−ガス熱交換器４を、凝縮側４ａの出口の冷媒を気液二相状態となるようなでの熱交換量に設定すれば、洗浄運転時の洗浄冷媒の封入量を削減することが可能となる。
【００２１】
室外機４１内に冷媒を回収するポンプダウン運転を実施した場合、回収ボンベ５０内に回収した冷媒のみでは、洗浄冷媒として不足する恐れがあり、室外機４１内の液阻止弁６４及びガス阻止弁６９に併設したサービス口６４１、６９１以外に設置されたサービス口と配管洗浄装置４０ａの接続口２２（３２）とを、さらにサービス口とは別のサービス口と配管洗浄装置４０ａの接続口３１とをチャージホースを介して接続する。これにより、室外機４１内に回収した冷媒を液接続配管６５、ガス接続配管６８内及び配管洗浄装置４０ａ内に流出することが可能となり、洗浄冷媒の不足を防ぐことができる。
室外機４１内の液阻止弁６４及びガス阻止弁６９に併設したサービス口６４１、６９１以外に設置されたサービス口がない場合は、液阻止弁６４及びガス阻止弁６９側の液接続配管６５及びガス接続配管６８との接続口を封止栓で封止した後、液阻止弁６４及びガス阻止弁６９を開け、サービス口６４１、６９１と配管洗浄装置４０ａの接続口２２（３２）、３１とをチャージホースを介して接続することが良い。
【００２２】
洗浄運転が終了したら図８に示すように、液接続配管６５及びガス接続配管６８内の洗浄冷媒を回収ボンベ５０に回収する。（冷媒回収運転時の冷媒の流れについては、冷凍装置からの冷媒回収運転時の流れと同様である。）
以上の洗浄運転及び冷媒回収運転の一連の作業を自動化することが良く、洗浄運転であれば、洗浄すべき液接続配管６５及びガス接続配管６８の配管総長に応じた必要洗浄時間を予め求めておき、洗浄時間をタイマ等で設定しておけば良い。冷媒回収運転であれば、低圧側圧力を圧力測定装置で監視しておき、要求される最低限の圧力となった時点で冷媒回収運転を終了する。
【００２３】
図２の配管洗浄装置４０ｂは、他の実施の形態を示し、冷媒圧縮機１ｂの吐出側に油分離器１２を配置したものである。冷媒圧縮機１ｂから吐出した冷凍機油は、油分離器１２により分離され、冷凍機油はガス冷媒の密度よりも大きいので、重力により油分離器１２の下方に沈殿（１３）する。分離した冷凍機油１３は、返油回路１４により冷媒圧縮機１ｂの吸入側に戻される。油分離器１２から冷媒圧縮機１ｂの吸入側に戻される冷凍機油の量は返油回路用キャピラリ１４ａの絞り量により調整することができ、冷媒圧縮機１ｂ内の冷凍機油の油面が異常に上昇することを抑える。これにより、冷媒圧縮機１ｂ内の冷凍機油が無くならない、あるいは冷媒圧縮機１ｂ内の冷凍機油がの著しく減少することを抑えることができるので、配管洗浄装置４０ｂのメンテナンス時間を低減し、信頼性を向上できる。
【００２４】
図３の配管洗浄装置４０ｃは、さらに他の実施の形態を示し、液−ガス熱交換器４の凝縮側４ａと阻止弁５との間から、液単相冷媒または気液二相冷媒を、液バイパス回路用キャピラリ１５ａを備えた液バイパス回路１５を介して冷媒圧縮機１ｂの吸入側に戻すものであり、これにより、冷媒圧縮機１ｂ温度の異常上昇を抑えることができる。
【００２５】
図４の配管洗浄装置４０ｄは、さらに他の実施の形態を示し、空気熱交換器２を凝縮器２ａ、蒸発器２ｂとしてそれぞれ独立にしたもので、より効率を向上できる。
【００２６】
【発明の効果】
以上説明したように、本発明によれば、既設の冷凍装置に封入された冷媒のみ、もしくは若干の洗浄冷媒を別途用意することで、既設配管内に残留した冷凍機油の量を低減し、新規に接続する室外機に封入された冷凍機油の劣化を抑制し、することで、冷凍装置の信頼性を向上することができる。
【図面の簡単な説明】
【図１】本発明による一実施の形態の配管洗浄装置を示すサイクル系統図。
【図２】他の実施の形態の配管洗浄装置を示すサイクル系統図。
【図３】さらに、他の実施の形態の配管洗浄装置を示すサイクル系統図。
【図４】さらに、他の実施の形態の配管洗浄装置を示すサイクル系統図。
【図５】室外機のみを接続して配管洗浄運転をするときのサイクル系統図。
【図６】
室外機と室内機を接続して配管洗浄運転をするときのサイクル系統図。
【図７】室外機のみを接続して冷媒回収運転をするときのサイクル系統図。
【図８】
室外機と室内機を接続して冷媒回収運転をするときのサイクル系統図。
【符号の説明】
１ａ、１ｂ、１ｃ…冷媒圧縮機、２、２ａ、２ｂ…空気熱交換器、３、３ａ、３ｂ…送風装置、４…液−ガス熱交換器、４ａ…凝縮器、４ｂ…蒸発器、５、６…阻止弁、７…減圧装置（キャピラリ）、８…異物分離装置、１２…油分離器、３１、３２、３３…接続ポート、４０ａ、４０ｂ、４０ｃ、４０ｄ…配管洗浄装置、４１…室外機、４２ａ、４２ｂ…室内機、５０…冷媒回収ボンベ、５１…ガス側接続口、５２…液側接続口、５３、５４…チャージホース、５５、５６、５６ａ…接続配管、６４…液阻止弁、６４１…液阻止弁サービス口、６５…液接続配管、６８…ガス接続配管、６９…ガス阻止弁、６９１…ガス阻止弁サービス口。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a pipe cleaning apparatus and a pipe cleaning method for cleaning a connection pipe used for a refrigerating apparatus including an air conditioner and a refrigerator using a refrigerating cycle.
[0002]
[Prior art]
As a method for cleaning the piping of a refrigeration system including an air conditioner and a refrigerator, a refrigeration cycle different from the existing refrigeration system is used to clean the piping using the same refrigerant as the refrigerant used for the refrigeration system, and to clean the inside of the piping. Cleaning to remove dust such as swarf generated at the time of cutting the pipe remaining on the pipe, debris, and oxide film (copper oxide) generated on the inner surface of the pipe during welding of the pipe, and water remaining in the pipe It is known that the dust and moisture mixed in the refrigerant are removed by a filter disposed in a connection pipe between a circulating pump for cleaning pipes and a check valve, which is described in, for example, JP-A-2001-183035.
[Patent Document 1]
JP 2001-183035 A
[Problems to be solved by the invention]
In the above prior art, when the refrigerating machine oil is dissolved in the cleaning refrigerant, the cleaning refrigerant and the refrigerating machine oil are not separated, and in order to remove the refrigerating machine oil remaining in the existing piping, a new cleaning refrigerant must be separately added. It is necessary to prepare. In the case of a multi-type air conditioner with multiple indoor units connected or a system with a long piping length, where the amount of refrigerating machine oil remaining in the existing piping is large, depending on the washing condition in the piping, a new 100 kg or more A cleaning refrigerant is required.
[0004]
An object of the present invention is to reduce the amount of refrigerating machine oil remaining in an existing pipe, suppress deterioration of refrigerating machine oil enclosed in a newly connected outdoor unit, and improve the reliability of a refrigerating apparatus in a refrigerating cycle pipe. A cleaning apparatus and a pipe cleaning method are provided.
[0005]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides a refrigeration apparatus having a refrigeration cycle connected by a liquid connection pipe and a gas connection pipe, and circulates a refrigerant through the liquid connection pipe and the gas connection pipe to perform cleaning. In the pipe cleaning apparatus for a refrigeration cycle to be performed, the pipe cleaning apparatus includes a refrigerant compressor, an air heat exchanger, a decompression device, and an evaporator that are sequentially connected to form a vapor compression refrigeration cycle, and the evaporator and the refrigerant compressor And a foreign matter separating device is disposed between the liquid connecting pipe and the gas connecting pipe to circulate the cleaning refrigerant condensed by the air heat exchanger.
[0006]
Further, in the above, it is preferable that an oil separator is arranged on the discharge side of the refrigerant compressor, and the refrigerating machine oil separated by the oil separator is led out to the suction side of the refrigerant compressor.
Further, in the above, it is preferable that a part of the washing refrigerant condensed by the air heat exchanger is introduced into the suction side of the refrigerant compressor via the liquid bypass circuit pressure reducing device.
Further, a liquid-gas heat exchanger that performs heat exchange between the refrigerant condensed in the air heat exchanger and the refrigerant that has been depressurized by the decompression device through the liquid connection pipe and the gas connection pipe. It is desirable to provide.
[0007]
Further, the present invention provides a refrigeration cycle pipe cleaning method for circulating a refrigerant through the liquid connection pipe and the gas connection pipe for cleaning the refrigerating apparatus having the refrigeration cycle connected by the liquid connection pipe and the gas connection pipe. A method, wherein a refrigerant compressor, an air heat exchanger, a decompression device, and an evaporator are sequentially connected to the liquid connection pipe and the gas connection pipe, and a foreign matter separation device is provided between the evaporator and the refrigerant compressor. A recovery tank is connected to the disposed pipe cleaning apparatus and the pipe cleaning apparatus, and a refrigerant recovery operation is performed in which the high-temperature and high-pressure refrigerant discharged from the refrigerant compressor is condensed by the air heat exchanger and introduced into the recovery cylinder. The collected liquid refrigerant flows out and circulates into the liquid connection pipe and the gas connection pipe, flows into the pipe cleaning device, depressurizes the inflowing refrigerant by the decompression device, evaporates the refrigerant by the evaporator, and removes the foreign matter. Minute And performs pipe cleaning operation and to be taken into the refrigerant compressor via a device.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 shows a cycle system diagram according to one embodiment, FIG. 5 shows a cycle system diagram when performing a pipe washing operation using the one shown in FIG. 1, and FIG. 7 shows a cycle system diagram during a refrigerant recovery operation. ing.
[0009]
After operating the refrigerating device, the refrigerating machine oil discharged together with the refrigerant from the refrigerant compressor remains in the piping. The remaining refrigerating machine oil deteriorates after standing for a long time, and the total acid value and peracid value of the refrigerating machine oil increase. If only the outdoor unit or the outdoor unit and indoor unit are replaced with new ones by diverting the existing piping after operating the refrigeration system for a long time, the new outdoor unit may be replaced by a new one due to the effect of the deteriorated oil remaining in the existing piping. The deterioration of the enclosed refrigerating machine oil is accelerated, and the chemical wear of the sliding portion of the refrigerant compressor is promoted. Further, the refrigerant compressor may fail due to the occurrence of a copper plating phenomenon, poor insulation of the motor material, and the like, and the life of the refrigerant compressor may be shortened.
Further, when the refrigerant sealed in the refrigeration apparatus that has been operated for a long time is HCFC-22 and the refrigerant sealed in the newly connected outdoor unit is an HFC-based refrigerant (for example, R-410A, R-407C), the existing refrigerant is used. The refrigeration oil for HCFC-22 remaining in the piping is not dissolved in the HFC-based refrigerant, so it is clogged with a capillary or the like, and the reliability is further reduced.
[0010]
In the pipe cleaning device 40a of FIG. 1, the oil level gauge 10 is arranged in the refrigerant compressor 1a so that the amount of oil in the refrigerant compressor 1a can be seen from outside the refrigerant compressor 1a. The refrigerant compressor 1a discharges refrigerating machine oil in the refrigerant compressor 1a together with the refrigerant. Therefore, the refrigerating machine oil in the refrigerant compressor 1a is lost unless it is supplied from the suction side of the refrigerant compressor 1a, so that the sliding part of the refrigerant compressor 1a cannot be refueled, and the sliding part seizes and the refrigerant compressor 1a Breaks down. In the pipe cleaning device 40a, the foreign matter separating device 8 is arranged on the suction side of the refrigerant compressor 1a, and the refrigerating machine oil is separated by the foreign matter separating device 8, so that the refrigerating machine oil does not return to the refrigerant compressor 1a. Therefore, the refrigerating machine oil amount in the refrigerant compressor 1a is confirmed from the oil level gauge 10, and when the refrigerating machine oil becomes equal to or less than the specified amount, the refrigerating machine oil is added from the oil supply port 24.
[0011]
A pipe cleaning device according to an embodiment will be described with reference to FIGS.
After recovering the refrigerant in the refrigeration system configured by the existing outdoor unit 41 filled with CFC or HCFC-based refrigerant as the refrigerant, the liquid connection pipe 65 and the gas connection pipe 68 that connect the existing indoor units 42a and 42b, respectively, The pipe cleaning device 40a is connected. After or without performing the pump-down operation for collecting the refrigerant in the outdoor unit 41, the refrigerant in the liquid connection pipe 65 and the gas connection pipe 68 and the refrigerant in the indoor units 42a and 42b is collected in the empty collection cylinder 50. . FIG. 8 shows a connection state between the refrigeration apparatus and the pipe cleaning apparatus when the refrigerant is collected in the empty collection cylinder 50, and the service port 641 provided along with the liquid prevention valve 64 or the gas prevention valve 69 of the outdoor unit 41 or 691 and the blocking valve 6 of the pipe cleaning device 40a are connected using the connection pipe 56a (in FIG. 8, for example, the service port 691 on the gas blocking valve 69 side is connected to the blocking valve 6 of the pipe cleaning device 40a. There).
[0012]
The collection cylinder 50 is evacuated in advance to remove air from the collection cylinder 50, and the gas-side connection port 51 of the evacuated collection cylinder 50 and the connection port 31 of the pipe cleaning device 40 a are connected to the liquid of the collection cylinder 50. The side connection port 52 and the connection port 23 (33) of the pipe cleaning device 40a are connected using charge hoses 53 and 54.
[0013]
Next, the refrigerant recovery operation of the pipe cleaning device 40a is performed, and the flow of the refrigerant at this time will be described.
The pipe cleaning device 40a operates with the blocking valve 5 closed, the blocking valve 6 opened, and the solenoid valve 20 closed. The high-temperature and high-pressure refrigerant discharged from the refrigerant compressor 1a is condensed in the air heat exchanger 2 and becomes a high-pressure liquid refrigerant or a gas-liquid two-phase refrigerant. After the operation of the refrigerant compressor 1 a, the high-pressure liquid refrigerant or the gas-liquid two-phase refrigerant is introduced into the recovery cylinder 50 by opening the electromagnetic valve 23. Further, since the suction side of the refrigerant compressor 1a has a low pressure, the refrigerant in the existing refrigeration system is introduced into the pipe cleaning device 40a via the service port 691, the connection pipe 56a, and the blocking valve 6.
[0014]
In order to shorten the time of the refrigerant recovery operation, the solenoid valve 21 of the pipe cleaning device 40a is opened, and the gas phase in the recovery cylinder 50 is recovered from the gas side connection port 51 of the recovery cylinder 50 into the pipe cleaning device 40a. Is also good.
During the refrigerant recovery operation, the pressure reducing devices 71a and 71b, which are components of the existing indoor units 42a and 42b, are fully opened. If the pressure reducing devices 71a and 71b cannot be set to the fully opened state, the refrigerant is collected not only from the service port 691 but also from the service port 641.
[0015]
After performing the refrigerant recovery operation as described above, a cleaning operation of the existing liquid connection pipe 65 and gas connection pipe 68 is performed. A method of connecting the pipe cleaning device 40a during the pipe cleaning operation to the existing refrigeration device after the refrigerant is recovered will be described.
During the refrigerant recovery operation, when a pump-down operation for recovering the refrigerant in the outdoor unit 41 is performed, the liquid blocking valve 64 and the gas blocking valve 69 are fully closed, and then the liquid connecting pipe 65 and the gas connecting pipe 68 are connected to the liquid. The blocking valve 64 and the gas blocking valve 69 are separated. The separated liquid connection pipe 65 and gas connection pipe 68 are connected to the blocking valves 5 and 6 of the pipe cleaning device 40a via the connection pipes 55 and 56. If the decompression devices 71a, 71b of the indoor units 42a, 42b can be fully opened, the decompression devices 71a, 71b are connected with the indoor units 42a, 42b connected to the liquid connection pipe 65 and the gas connection pipe 68. When it cannot be set to the fully opened state, the indoor units 42a and 42b are removed from the liquid connection pipe 65 and the gas connection pipe 68, and the liquid connection pipe 65 and the gas connection pipe 68 are connected to bypass branch pipes 66a having on-off valves 67a and 67b. 66b. In this state, the cleaning refrigerant is not sealed in the liquid connection pipe 65 and the gas connection pipe 68 to be cleaned. In order to perform the pipe cleaning operation, the cleaning refrigerant is sealed in the liquid connection pipe 65 and the gas connection pipe 68 and then performed. The method of charging the cleaning refrigerant and the flow of the cleaning refrigerant during the pipe cleaning operation will be described with reference to FIG.
[0016]
As the cleaning refrigerant, a refrigerant compatible with the refrigerating machine oil used in the refrigerating machine remaining in the liquid connection pipe 65 and the gas connection pipe 68 to be cleaned is selected. If there is compatibility between the refrigerant used in the refrigeration apparatus and the refrigerating machine oil, the refrigerant used in the refrigeration apparatus may be used as the cleaning refrigerant.
When the pump-down operation for collecting the refrigerant in the outdoor unit 41 is not performed and all the refrigerant is collected in the collection cylinder 50 in the refrigerating apparatus, as shown in FIG. 8, the gas in the collection cylinder 50 in which the refrigerant has been collected is collected. The connection port 51 is connected to the connection port 31 of the pipe cleaning device 40a, and the liquid connection port 52 of the recovery cylinder 50 and the connection port 23 (33) of the pipe cleaning device 40a are connected by using charge hoses 53, 54. .
[0017]
Before the cleaning operation, the insides of the liquid connection pipe 65 and the gas connection pipe 68 are evacuated. The pipe cleaning device 40a operates with the blocking valves 5 and 6 open and the solenoid valve 21 closed. When the electromagnetic valve 23 is opened in this state, the refrigerant in the recovery cylinder 50 flows into the liquid connection pipe 65 and the gas connection pipe 68 and into the pipe cleaning device 40a. Thereafter, by starting the refrigerant compressor 1a and opening the solenoid valve 20, the high-pressure refrigerant discharged from the refrigerant compressor 1a is introduced from the gas side connection port 51 of the recovery cylinder 50, and the pressure in the recovery cylinder 50 is reduced by pipe cleaning. The pressure becomes higher than the pressure of the connection port 23 (33) of the device 40a, and all the liquid refrigerant in the recovery cylinder 50 flows out into the liquid connection pipe 65 and the gas connection pipe 68 and into the pipe cleaning device 40a.
[0018]
The high-temperature and high-pressure refrigerant discharged from the refrigerant compressor 1a is condensed in the air heat exchanger 2 and becomes a high-pressure liquid refrigerant or a gas-liquid two-phase refrigerant. The liquid-gas heat exchanger 4 (plate heat exchanger or double-tube heat exchanger) Exchanger). Then, after the refrigerant is heat-exchanged in the liquid-gas heat exchanger 4, the refrigerant circulates through the connection pipe 55 in the liquid connection pipe 65 and the gas connection pipe 68 to be cleaned, and the liquid connection pipe 65 and the gas connection pipe After the foreign matter (refrigerating machine oil mainly used in the refrigerating machine) remaining in the 68 is dissolved in the washing refrigerant, the foreign matter flows into the pipe washing device 40a from the blocking valve 6 through the connection pipe 56. Thereafter, the pressure of the cleaning refrigerant is reduced by the decompression device 7, and the refrigerant is evaporated on the evaporation side 4b of the liquid-gas heat exchanger 4 to become a gas single phase.
[0019]
The gas single-phase cleaning refrigerant and the foreign substances dissolved in the cleaning refrigerant are introduced into the foreign substance separation device 8, and the foreign substances heavier than the density of the gas single-phase cleaning refrigerant precipitate under the foreign substance separation device 8 by gravity. (11) It is separated from the cleaning refrigerant. The gas single-phase cleaning refrigerant containing no foreign matter is led out to the suction side of the refrigerant compressor 1a.
[0020]
As described above, in the liquid connection pipe 65 and the gas connection pipe 68 to be cleaned, the cleaning refrigerant having a high cleaning ability without any contamination is constantly circulated, so that the cleaning ability of the pipe cleaning device 40a is maintained at a high level. It is possible to do. In addition, since the refrigerant supplied to the refrigerant compressor 1a is a refrigerant after foreign matter is separated, the foreign matter does not mix with the refrigerating machine oil sealed in the pipe cleaning device 40a, so that reliability can be improved.
If the liquid-gas heat exchanger 4 is set to an amount of heat exchange such that the refrigerant at the outlet of the condensing side 4a is in a gas-liquid two-phase state, the amount of cleaning refrigerant sealed during the cleaning operation can be reduced. It becomes possible.
[0021]
When the pump-down operation for collecting the refrigerant in the outdoor unit 41 is performed, the refrigerant collected in the collection cylinder 50 alone may be insufficient as the cleaning refrigerant, and the liquid blocking valve 64 and the gas blocking valve in the outdoor unit 41 may be insufficient. A service port provided in addition to the service ports 641 and 691 attached to 69 and the connection port 22 (32) of the pipe cleaning device 40a, and a service port different from the service port and the connection port 31 of the pipe cleaning device 40a. Is connected via a charge hose. Thereby, the refrigerant collected in the outdoor unit 41 can flow out into the liquid connection pipe 65, the gas connection pipe 68, and the pipe cleaning device 40a, and shortage of the cleaning refrigerant can be prevented.
If there is no service port provided other than the service ports 641 and 691 provided in the outdoor unit 41 along with the liquid blocking valve 64 and the gas blocking valve 69, the liquid connecting pipe 65 on the liquid blocking valve 64 and the gas blocking valve 69 side and After sealing the connection port with the gas connection pipe 68 with a sealing plug, the liquid blocking valve 64 and the gas blocking valve 69 are opened, and the service ports 641 and 691 and the connection ports 22 (32) and 31 of the pipe cleaning device 40 a are connected. Is connected via a charge hose.
[0022]
When the cleaning operation is completed, the cleaning refrigerant in the liquid connection pipe 65 and the gas connection pipe 68 is recovered in the recovery cylinder 50 as shown in FIG. (The flow of the refrigerant during the refrigerant recovery operation is the same as the flow during the refrigerant recovery operation from the refrigerating device.)
It is preferable to automate a series of operations of the cleaning operation and the refrigerant recovery operation described above. In the case of the cleaning operation, a required cleaning time according to the total length of the liquid connection pipe 65 and the gas connection pipe 68 to be cleaned is obtained in advance. The cleaning time may be set by a timer or the like. In the case of the refrigerant recovery operation, the low pressure side pressure is monitored by the pressure measuring device, and the refrigerant recovery operation is terminated when the required minimum pressure is reached.
[0023]
A pipe cleaning device 40b of FIG. 2 shows another embodiment, in which an oil separator 12 is arranged on the discharge side of a refrigerant compressor 1b. The refrigerating machine oil discharged from the refrigerant compressor 1b is separated by the oil separator 12, and the refrigerating machine oil is settled below the oil separator 12 by gravity (13) because the refrigerating machine oil is larger in density than the gas refrigerant. The separated refrigerating machine oil 13 is returned to the suction side of the refrigerant compressor 1b by the oil return circuit 14. The amount of the refrigerating machine oil returned from the oil separator 12 to the suction side of the refrigerant compressor 1b can be adjusted by the throttle amount of the oil return circuit capillary 14a, and the oil level of the refrigerating machine oil in the refrigerant compressor 1b becomes abnormal. Suppress the rise. As a result, the refrigerating machine oil in the refrigerant compressor 1b is not lost, or the refrigerating machine oil in the refrigerant compressor 1b can be prevented from being significantly reduced. Therefore, the maintenance time of the pipe cleaning device 40b can be reduced, and the reliability can be reduced. Can be improved.
[0024]
The pipe cleaning device 40c in FIG. 3 shows still another embodiment, in which a liquid single-phase refrigerant or a gas-liquid two-phase refrigerant is supplied from between the condensing side 4a of the liquid-gas heat exchanger 4 and the blocking valve 5, The refrigerant is returned to the suction side of the refrigerant compressor 1b via the liquid bypass circuit 15 having the liquid bypass circuit capillary 15a, whereby an abnormal rise in the temperature of the refrigerant compressor 1b can be suppressed.
[0025]
The pipe cleaning device 40d of FIG. 4 shows still another embodiment, in which the air heat exchanger 2 is independently provided as a condenser 2a and an evaporator 2b, so that the efficiency can be further improved.
[0026]
【The invention's effect】
As described above, according to the present invention, the amount of the refrigerating machine oil remaining in the existing piping is reduced by separately preparing only the refrigerant sealed in the existing refrigerating device or a small amount of the cleaning refrigerant. Thus, deterioration of the refrigerating machine oil sealed in the outdoor unit connected to the refrigerating machine can be suppressed and the reliability of the refrigerating apparatus can be improved.
[Brief description of the drawings]
FIG. 1 is a cycle system diagram showing a pipe cleaning apparatus according to an embodiment of the present invention.
FIG. 2 is a cycle system diagram showing a pipe cleaning apparatus according to another embodiment.
FIG. 3 is a cycle system diagram showing a pipe cleaning apparatus according to another embodiment.
FIG. 4 is a cycle system diagram showing a pipe cleaning apparatus according to another embodiment.
FIG. 5 is a cycle system diagram when a pipe cleaning operation is performed by connecting only an outdoor unit.
FIG. 6
FIG. 3 is a cycle system diagram when a pipe cleaning operation is performed by connecting an outdoor unit and an indoor unit.
FIG. 7 is a cycle system diagram when a refrigerant recovery operation is performed by connecting only an outdoor unit.
FIG. 8
FIG. 3 is a cycle system diagram when a refrigerant recovery operation is performed by connecting an outdoor unit and an indoor unit.
[Explanation of symbols]
1a, 1b, 1c: Refrigerant compressor, 2, 2a, 2b: Air heat exchanger, 3, 3a, 3b: Blower, 4: Liquid-gas heat exchanger, 4a: Condenser, 4b: Evaporator, 5 6, blocking valve, 7: pressure reducing device (capillary), 8: foreign matter separating device, 12: oil separator, 31, 32, 33 ... connection port, 40a, 40b, 40c, 40d: pipe cleaning device, 41: outdoor , 42a, 42b ... indoor unit, 50 ... refrigerant collection cylinder, 51 ... gas side connection port, 52 ... liquid side connection port, 53, 54 ... charge hose, 55, 56, 56a ... connection pipe, 64 ... liquid check valve Reference numeral 641 denotes a liquid blocking valve service port, 65 denotes a liquid connecting pipe, 68 denotes a gas connecting pipe, 69 denotes a gas blocking valve, and 691 denotes a gas blocking valve service port.

Claims

For a refrigeration apparatus having a refrigeration cycle connected by a liquid connection pipe and a gas connection pipe, in a refrigeration cycle pipe cleaning apparatus for cleaning by circulating a refrigerant through the liquid connection pipe and the gas connection pipe,
In the pipe cleaning device, a refrigerant compressor, an air heat exchanger, a decompression device, and an evaporator are sequentially connected to form a vapor compression refrigeration cycle, and a foreign matter separation device is disposed between the evaporator and the refrigerant compressor. And a refrigerant condensed by the air heat exchanger is circulated in the liquid connection pipe and the gas connection pipe.

2. The piping according to claim 1, wherein an oil separator is arranged on a discharge side of the refrigerant compressor, and refrigeration oil separated by the oil separator is led to a suction side of the refrigerant compressor. 3. Cleaning equipment.

2. The piping according to claim 1, wherein a part of the washing refrigerant condensed by the air heat exchanger is introduced into the suction side of the refrigerant compressor via a pressure reducing device for a liquid bypass circuit. Cleaning equipment.

2. The heat exchanger according to claim 1, wherein heat is exchanged between the refrigerant condensed in the air heat exchanger and the refrigerant that has been depressurized by the decompression device through the liquid connection pipe and the gas connection pipe. A pipe cleaning device provided with a liquid-gas heat exchanger.

For a refrigeration apparatus having a refrigeration cycle connected by a liquid connection pipe and a gas connection pipe, a refrigeration cycle pipe cleaning method of circulating a refrigerant through the liquid connection pipe and the gas connection pipe to perform cleaning.
A pipe cleaning in which a refrigerant compressor, an air heat exchanger, a decompression device, and an evaporator are sequentially connected to the liquid connection pipe and the gas connection pipe, and a foreign matter separation device is disposed between the evaporator and the refrigerant compressor. A recovery cylinder is connected to the apparatus and the pipe cleaning device, and a refrigerant recovery operation is performed in which the high-temperature and high-pressure refrigerant discharged from the refrigerant compressor is condensed by the air heat exchanger and introduced into the recovery cylinder.
The collected liquid refrigerant flows out and circulates into the liquid connection pipe and the gas connection pipe, flows into the pipe cleaning device, depressurizes the inflowing refrigerant by the decompression device, evaporates the refrigerant by the evaporator, and removes the foreign matter. A pipe cleaning method comprising performing a pipe cleaning operation of causing a suction to the refrigerant compressor through a separation device.