4.1.1 Change the impeller
The flexible impeller is practically the only piece that may break down. Its breakage may be due to dry
operation (hard, polished and cracked outside faces, or even one or more blades missing), pumping
abrasive liquids (points on the blades worn), excessive pressure (blades cracked or broken in half),
cavitation (lack of material on the blades, especially in the middle) or simply for having reached the end
of its useful life.
Disassembly:
Disconnect the motor (7), loosen and remove clamp (3). They will be free so that the front cover (5), the
body (7) and the impeller (4) that need to be replaced can be removed.
Assembly:
For assembly, follow the instructions in reverse. When fitting the new impeller there is no need for any
kind of lubricant or grease.
4.1.2 Changing the mechanical seal
A mechanical seal is made up of two parts: the fixed and the turning part. The pump's seal is achieved
through the friction faces of these parts. The use of very abrasive products or especially using the pump
without liquid may damage these faces and/or their joints. In this case the mechanical seal must be
changed.
Disassembly:
Proceed in the same manner as for disassembling the impeller. Remove the back cover (6) that
integrates the stainless steel stationary friction side (model F-1) or contains the fixed part of the
mechanical seal (models F-15, F-2 and F-5). Finally, turn the turning part of the mechanical seal (8)
above the shaft.
Check the state of the shaft to see whether needs to be replaced due to notches or wear. It is not
possible to change the shaft on model F-1 because it is the shaft of the motor and the motor needs to
be changed completely.
Assembly:
For assembly, follow the instructions in reverse. Assemble the stationary part of the mechanical seal at
pressure (8) in the back cover housing (6) if it is not integrated. Insert the turning part of the mechanical
seal placing a little neutral grease or soapy water on the shaft (5) to help it go in.
It is advisable to inspect the condition of all of the above-mentioned parts, every 2,500 h of
process or every six months (the lesser of the two) with the aim of maintaining the use of
the pump within safety parameters.
For the mechanical seal and the motor is recommended to follow the premises established
by the original manufacturers.
Except where the inspection and maintenance plans established by the user do not
determine different intervals.
The pump must never be turned dry!
4.2 Guarantee
All Bominox pumps are guaranteed for one year from the delivery date on manufacturing defects, as
long as they are used following the recommendations of the service instructions and pursuant to the
specifications indicated in the conditions of sale, and do not have wear as a result of service in severe
conditions (e.g. extremely corrosive or abrasive).
The guarantee shall be void if there are modifications to the pump that are not expressly authorised by
Bominox, the parts used are not original, all the pumps have been used incorrectly or exposed to strong
pressure.
Bominox, S.A. - Installation and Maintenance Instructions
EN 11