Know-how| 407 How to tighten gland packing |
| However, when using a ground gasket only of the PTFE material, attention is necessary for how to tighten the gland packing. When the pump is assembled, it tightens in the extent that the gland touches. It tightens gradually spending about 30 minutes after the pump is started, and it reaches the proper leakage. |
| 406_05 Pump selection - operating conditions |
| If the pumping temperature is high, it is necessary to cool the bearing, the stuffing box, and the pedestal. |
| 406_04 Pump selection - liquid characteristics |
| When a pump is selected according to the characteristic of the handling liquid, some might be noted. |
| 406_03 Pump selection - flow until purchase order |
| The flow until purchase order is as follows at the API 610 application. |
| 406_02 Pump selection - applied standards |
| When selecting pumps, a pump price is different according to the applied standard. |
| 406_01 Pump selection - general |
| When selecting pumps, there are some key points such as Reliability, Price, Efficiency, Maintenance, Mean time between failure (MTBF), Life cycle cost, Spare parts management, Favor (vendor, model), After-sales service, Operation frequency, Purchase time, Interchangeability, Delivery time, and etc. |
| 405 Specification for pump selection |
| To select an appropriate pump, the following specifications are required. In other words, if the following specifications are not clear, it would become the origin of the trouble. |
| 404 Pump Specific Speed m |
| In centrifugal pumps, there are capacity, total head, efficiency, speed, NPSH3 etc. as values to show the characteristic. The size and shape of a pump change variously by the values of capacity, total head and speed. Therefore, if you can show the characteristic and the shape of the pump by using one number of characteristics, it is possible to use for the performance assessment, the proportional design, and the performance expectation, etc. , and it becomes very convenient. |
| 403 Pump standardization flow |
| As introduced before, pump standardization is gUnite the quality, shape, and the size of a pump with standards. Interchangeability
is improved by it.h In general, when the pump of a model with a lot of
numbers of production is standardized, the advantage grows. @Here, it explains how to standardize a pump by concretely using flow. |
| 402 Pump protection instruments |
| We have a minimum flow line installed beforehand because abnormality is not caused to a pump, and have instruments@such as the vibration detector, thermometer, and leakage detector to stop a pump detecting abnormality of the function as well. In a word, there is no standard necessary protection instrument. However, I think that it is good to decide yes/no by thinking about the followings. |
| 401 Pump standardization preface |
| Pump standardization is gUnite the quality, shape, and the size of a pump with standards. Interchangeability is improved by it.h |
| Is the pump made of cast iron or of stainless steel? |
| It is worth examining made of stainless steel when using it for five years or more, though it is enough if only 2 or 3 years are used by cast iron. |
| What one is good as for the motor? |
| Using the motor in two poles out of four poles, the purchase price of the pump and the motor becomes cheap. However, it is necessary to consider the problem of the cavitation, the vibration and the noise. The rotational speed of the motor is decided according to the system requirements and the budget, etc. |
| The size of pump? |
| The purchase price rises in a larger pump. Because there must be a best
efficiency point in the pump, the pump that can be driven in the vicinity
is selected or it adjusts it in the piping system. |
| Is maintenance important? |
| Same as people, It is possible to prolong the life span by maintaining the pump regularly. Moreover, the large-scale accident can be prevented beforehand. |
| How will the pump technology become it in the future? |
| The emphasis has moved to the improvement of reliability and the development of the recycle technology. The idea of not buying "One" as these solutions and buying "Service" ([sahbisaijingu]) has come out though the selection of the pump that thinks about the life cycle cost is necessary. |