VACUUM SYSTEM真空系統(tǒng)
雙級(jí)真空泵組冷凍干燥過程中所需要的真空泵及相關(guān)閥門組成的真空泵組，真空系統(tǒng)安裝在機(jī)架上。
真空系統(tǒng)配置包括帶有隔離閥的雙真空泵并聯(lián)運(yùn)行，一旦控制壓力達(dá)到要求，一臺(tái)真空泵停止，轉(zhuǎn)為備份。雙泵系統(tǒng)在周期中自動(dòng)切換。
The vacuum pump group composed of vacuum pump and related valves in the freeze-drying process of the two-stage vacuum pump group, the vacuum system is installed on the frame.
Vacuum system configuration includes double vacuum pump with isolation valve running in parallel. Once the control pressure meets the requirements, a vacuum pump stops and is converted to backup. The double pump system switches automatically during the cycle.
真空泵內(nèi)部的連接和與冷阱的連接通過AISI304L 不銹鋼管。真空系統(tǒng)與冷凝器之間使用全自動(dòng)、氣動(dòng)蝶閥使真空系統(tǒng)與凍干機(jī)隔離。如果出現(xiàn)停電事故，閥門自動(dòng)關(guān)閉以防止真空系統(tǒng)污染冷凝器并減少了在恢復(fù)來電之前由于壓力升高導(dǎo)致的產(chǎn)品損失。每臺(tái)真空泵在泵進(jìn)口都安裝自動(dòng)蝶閥，可以確保系統(tǒng)在作為‘備份泵’或停電時(shí)有效的隔離。在冷阱的隔離閥與泵之間安裝有一個(gè) Pirani 探頭。每臺(tái)泵的進(jìn)口上都預(yù)留帶閥門的接口，在系統(tǒng)檢查、維護(hù)時(shí)可以安裝Pirani 探頭。
Vacuum pump internal connection and cold trap connection through AISI304L stainless steel pipe. The vacuum system and condenser are fully automatic, and the pneumatic butterfly valve separates the vacuum system from the freeze-drying machine. In the event of a power outage, the valve is automatically closed to prevent the vacuum system from polluting the condenser and to reduce the loss of the product due to increased pressure before resuming the incoming call. Each vacuum pump is equipped with an automatic butterfly valve at the inlet of the pump to ensure that the system is effectively isolated as a backup pump or as a power outage. A Pirani probe is installed between the cold trap isolation valve and the pump. The interface with valve is reserved on the inlet of each pump Pirani probe can be installed during system inspection and maintenance.
Vacuum Measurement and Control真空測(cè)量和控制
箱體上裝有一個(gè)真空探頭。探頭輸出信號(hào)給PLC 及記錄儀，以顯示在SCADA 系統(tǒng)上并控制。
真空的自動(dòng)控制可以根據(jù)用戶的選擇采用兩個(gè)系統(tǒng)來實(shí)現(xiàn)：
? 摻氣 -通過調(diào)節(jié)閥和由PLC 數(shù)字輸出控制的通斷電磁隔離閥以受控的速率向箱體內(nèi)輸入氣體（空氣或選擇的其它氣體－通過控制面板可以選擇相關(guān)閥門）。
? 真空節(jié)流- 通過控制安裝在冷阱和真空系統(tǒng)之間的真空隔離閥。
The chamber is supplied with a vacuum gauge (see item 26). The gauge output is fed to the PLC for control purposes, recorded on the chart recorder and displayed within the Lyomax Compact system.
Automatic vacuum control is achieved by either of two systems according to user selection:
?Gas bleed - a gas (air or selected gas – the appropriate valve is selected via the control panel) is fed into the chamber at a rate controlled via a modulating valve (see item 27) and on/off solenoid isolation valve controlled by a digital PLC output.
?Vacuum throttling - by controlling the vacuum isolation valve installed between the condenser and vacuum system.
Leak Tightness泄漏率
由箱體和冷凝器及相關(guān)管路、閥門、入口過濾器（如安裝）及儀表組成的系統(tǒng)泄漏率對(duì)于不凝性氣體，可保持0.03mbarl/s 或更高。
The complete process system comprising chamber, condenser and associated pipework, valves, inlet filters (when fitted) and instruments shall have a leak rate of 0.03mbarl/s or better for non-condensable gases.
