2015-08-21
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| Symptom: | Cause: | Remedy: |
| Reciprocating pumps | ||
| Loss of suction | 1) Obstructions in the suction line. | Check suction valves. |
| 2) Air in the system. | Open the air cocks vents on the liquid end valve chest, leave them open until water flows out. | |
| Centrifugal pumps | ||
| A pump doesn't deliver any liquid | 1) Air in the pump case. | Let the air flow out. |
| 2) Insufficient speed of the pump. | Check the electromotor, bearings and gland box. | |
| 3) Excessive large pressure resulting from a partially clogged valve or some obstruction in the discharge line. | Check the valve and adjust it. | |
| 4) Clogged impeller passages. | Stop the pump and clean the impeller. | |
| 5) Ruptured suction line. | Stop the pump, eliminate leakages in the suction line. | |
| A pump operates at insufficient capacity | 1) Air leakage into the suction line or stuffing boxes. | Eliminate leakages. |
| 2) Mechanical defects such as worn wearing rings, impellers, stuffing box packing or sleeves. | Stop the pump, find the trouble and correct it. |
Exercise 7. Translate into English.
1. Производительность центробежного насоса равна 150 м3/ч. 2. Насосы спроектированы для подачи пресной и морской воды. 3. Корпус насоса снизу закрывается крышкой. 4. половинки разъемного насоса крепятся болтами. 5. Капли жидкости могут просачиваться через уплотнение. 6. Зазор между уплотнениями и буртиком очень мал. 7. Крылатка насаживается на вал и фиксируется шпонкой.
