Autoclave steam feed control - has second thermometer set to lower temp. than main thermometer to check temp. increase by time

摘要

The control system to establish irregular steam feed to an autoclave, for decatising woven piecegoods, has a second thermometer (T2) parallel to the main thermometer (T1), set to a lower temp. than the main unit. Should the set temp. be reached in a shorter time span than set in the timer (3), an autoclave (A) fault is indicated. Pref. the second thermometer (T2) is inserted into a separate channel (2) from the main thermometer, leading to a separate outlet which can be opened as an alternative to the main outlet. The timer (3) closes the second outlet, after a given time, simultaneously with the opening of the main outlet (1). The main channel (1) for the air outlet is connected to the exit (7) through the main outlet (8) and valve (9). The second outlet channel (2) is linked to the exit (7) through an additional outlet (10) behind the main outlet (8) in relation to the flow direction from the autoclave (A). At the start of each decating cycle, the valve (9) is closed and the other valve (11) is opened. A timer (3) controls the closing of one valve (11) synchronised with the opening of the other valve (9). A vacuum pump evacuates the autoclave (A), and steam is passed in (4) after or at the same time as the evacuation. At the start of the steam feed, the second outlet channel (11) and the valve (9) to the main outlet is closed. ADVANTAGE - The appts. gives a simple indication that the operating conditions are not correct, to prevent faulty treatment.