(1) sealing fluid system of packing seal
(2) when the pump conveys clean liquid, the sealing liquid is led out from the pump outlet, and the pump can be led out from the middle stage, and connected with the sealing liquid inlet at the sealing liquid ring through the connecting pipe.
(3) If any of the following conditions are met, an external sealing fluid system should be equipped.
(1) The suction height of the heat conduction oil pump exceeds 4.5m. At this time, a large number of air without filtration will enter the pump through the packing box, causing a great impact on the normal operation of the pump, the sealing liquid pressure is 70-172kpa,
② Discharge pressure is lower than 0.07mpa. Because the discharge pressure is too low, the discharge outlet of the pump cannot provide sufficient sealing fluid
Pressure.
(3) The delivery of hot water over 120'C, and there is not enough cooling (except boiler feed pump, because it cannot use liquid sealing ring),
(4) when conveying solid abrasive medium, such as mortar water and sewage, in order to improve the service life of filler, shaft or sleeve and reduce abrasion, clean liquid should be entered at the sealing liquid. The cleaning liquid can be supplied from the outside, and the external sealing liquid pressure should be greater than the side pressure of the packing chamber 70-I72kpa. But in order to reduce the dilution of the sealing medium, two rings of packing should be set between the sealing liquid ring and the packing chamber. The liquid can also be extracted from the discharge outlet of the oil pump and passed through the filter or centrifugal separator into the sealing liquid ring.
The hot well pump and condensate pump operate at a vacuum of 710mmHg. When conveying non-water media such as acid, gasoline, honey or viscous fluids, the design of the sealed chamber has no special consideration for the characteristics of these fluids.
(4) When the suction pressure of the pump is lower than atmospheric pressure, such as condensate pump, the throttle orifice plate should be added on the sealing liquid return suction pipe. That is, the sealing liquid from the pump outlet leads into the packing box. The sealing fluid from the packing box flows into the suction of the pump after passing through the orifice plate to prevent air leakage into the pump and control the sealing fluid flow.
(5) When the pressure of sealed indoor medium is lower than 103kPa and the temperature is lower than 90℃, cooling measures are not needed if there is enough leakage liquid passing through the packing seal.
(6) When the medium pressure in the sealed room is lower than 345kPa and the temperature is lower than 118℃, coolant shall be passed into the sealing ring. Coolant flow is 3.78L/min, the pressure is 34kPa lower than the medium pressure,
(7) When the medium pressure in the sealed room is lower than 690kPa and the temperature is lower than 131℃, coolant shall be passed into the sealing ring. The coolant flow was 3.781./rnin, and the pressure was 34 kpa lower than the medium pressure. Jacketed cooling is also required at the packing.
(8) If the sealed medium is easy to solidify, the pump should be heated in advance in the sealed chamber before starting. Steam or resistance tracing is available in the sealed chamber.
