Marine Engineering
177
Air Bottle, Air Compressor, Refrigeration, Air Cond. & Evaporator:
Air receiver: » Total capacity of air receivers must be sufficient to give at least 12 starts for reversible engine, and at least 6 starts for non-reversible engine, without refilling the receivers. » There must be two identical main air receivers and one emergency bottle for every vessel. Mountings:
1.
Fusible plug; composition – Bismuth 50%, Tin 30%, Lead 20%, Melting point: 220΄F (104.4΄C). Fitted at the reservoir's bottom or on reservoir at ship side, when relief valve (safety valve) is not directly fitted on the reservoir. Atmospheric relief valve; provided for back-up of fusible plug. In case of ER fire when CO₂ flooding is required, this valve is opened before evacuating ER. Spring loaded safety valve; Setting pressure: 32 bar (for 30 bar working pressure), with ≯ 10% rise in accumulation of pressure. May be fitted directly or with extension. Compensation ring; When a hole is cut or machined in pressure vessel, higher stresses will subject to the material around the hole, and to reduce this, compensation rings are fitted. It is a flange on which a valve or fitting is usually mounted. Manual Drain valve or Automatic Drain valve. Pressure gauges. Access doors. Main starting air valve, auxiliary starting air valve, filling valve, service air or whistle air valve.
2.
3.
4.
5. 6. 7. 8.
Internal surface coating: Graphite suspension in water, Linseed oil, Copal vanish or Epoxy coating having basic properties of anti-corrosive, anti-toxic or anti-oxidation. Safety devices on Main Air Bottle:
1. 2. 3. 4. 5.
Fusible plug. Pressure Relief Valve Atmospheric Relief Valve. Low Air Pressure alarm. Automatic or remote control Moisture Drain Valve.
Air Compressor: LP Relief Valve opening: Causes:
1. 2. 3.
HP suction valve leaking. Intercooler choked. Relief valve, jammed by foreign particles, in open position.
178
HP Relief Valve opening: Causes:
1. 2. 3.
HP
Air Bottle, Air Compressor, Refrigeration, Air Cond. & Evaporator:
Air receiver: » Total capacity of air receivers must be sufficient to give at least 12 starts for reversible engine, and at least 6 starts for non-reversible engine, without refilling the receivers. » There must be two identical main air receivers and one emergency bottle for every vessel. Mountings:
1.
Fusible plug; composition – Bismuth 50%, Tin 30%, Lead 20%, Melting point: 220΄F (104.4΄C). Fitted at the reservoir's bottom or on reservoir at ship side, when relief valve (safety valve) is not directly fitted on the reservoir. Atmospheric relief valve; provided for back-up of fusible plug. In case of ER fire when CO₂ flooding is required, this valve is opened before evacuating ER. Spring loaded safety valve; Setting pressure: 32 bar (for 30 bar working pressure), with ≯ 10% rise in accumulation of pressure. May be fitted directly or with extension. Compensation ring; When a hole is cut or machined in pressure vessel, higher stresses will subject to the material around the hole, and to reduce this, compensation rings are fitted. It is a flange on which a valve or fitting is usually mounted. Manual Drain valve or Automatic Drain valve. Pressure gauges. Access doors. Main starting air valve, auxiliary starting air valve, filling valve, service air or whistle air valve.
2.
3.
4.
5. 6. 7. 8.
Internal surface coating: Graphite suspension in water, Linseed oil, Copal vanish or Epoxy coating having basic properties of anti-corrosive, anti-toxic or anti-oxidation. Safety devices on Main Air Bottle:
1. 2. 3. 4. 5.
Fusible plug. Pressure Relief Valve Atmospheric Relief Valve. Low Air Pressure alarm. Automatic or remote control Moisture Drain Valve.
Air Compressor: LP Relief Valve opening: Causes:
1. 2. 3.
HP suction valve leaking. Intercooler choked. Relief valve, jammed by foreign particles, in open position.
178
HP Relief Valve opening: Causes:
1. 2. 3.
HP