UB USER INSTRUCTIONS ENGLISH 71569247 07-04

®

q)Remove impellers, casing rings, diaphragm plate complete with its bush together with the impeller key.

If impellers prove difficult to remove, the use of heat is permissible. Refer to Section 1.6, Safety, APPLYING HEAT TO REMOVE IMPELLER, for more details.

r)If it is required to remove the diaphragm plate bush then remove the 4 countersunk screws and push out the bush.

s)If impeller rings are also fitted, they are shrunk onto the impeller and fixed with locking screws between their diametric mating surfaces.

t)To remove the impeller rings, remove the locking screws and heat up the ring until it slides off easily.

6.9 Examination of parts

Used parts must be inspected before assembly to ensure the pump will subsequently run properly.

In particular, fault diagnosis is essential to enhance pump and plant reliability.

6.9.1 Casing, seal housing and impeller

a)Inspect for excessive wear, pitting, corrosion, erosion or damage and any sealing surface irregularities.

b)Replace as necessary.

6.9.2Shaft and sleeve (if fitted) Replace if grooved, pitted or worn.

6.9.3Gaskets and O-rings

After dismantling, discard and replace.

6.9.4 Bearings

It is recommended that bearings are not re-used after any removal from the shaft.

6.9.5Bearing isolators, labyrinths or lip seals (if fitted)

a)The lubricant, bearings and bearing housing seals are to be inspected for contamination and damage.

b)If bearing damage is not due to normal wear and the lubricant contains adverse contaminants, the cause should be corrected before the pump is returned to service.

c)Labyrinth seals and bearing isolators should be inspected for damage but are normally non- wearing parts and can be re-used.

d)Bearing seals are not totally leak free devices. Oil from these may cause staining adjacent to the bearings.

6.10 Assembly

To assemble the pump consult the sectional drawings, see section 8, Parts list and drawings.

Ensure threads, gasket and O-ring mating faces are clean. Apply thread sealant to non-face sealing pipe thread fittings. Coat the outside diameter of the dowel bushings with pipe compound prior to installation.

6.10.1 Impeller wear rings

a)Impeller rings (when fitted) should be heated up to approximately 100 ºC (212 ºF) using a hotplate or hot oil bath and then slipped onto the impeller and pressed down to the shoulder. (Do NOT use a steel hammer to knock them into position.)

b)Drill and tap 3 holes approximately 120 degrees apart into the diametral mating faces of the ring and impeller and insert socket head screws.

(The existing half tapped holes from the removed impeller ring cannot be re-used.)

46

45

6.10.2 Pre-assembly of casing gasket

a)Fit casing gasket to the bottom half horizontal flange using a small amount of contact adhesive to prevent movement when the top half is fitted. Do not apply adhesive to the top surface of the gasket.

b)It is important that the external corner of the casing gasket face and the stuffing box face is as sharp as possible.

Do not chamfer with a file.

c)If necessary trim gasket to match volute profile. Do not trim to stuffing box face at this stage.

6.10.3 Rotating element and bearing bracket

a)Ensure all gaskets and O-rings are renewed and replaced in the correct position during assembly.

b)Assemble the impellers on the shaft. It is important to mount the impellers so that the vane tips point away from the apparent flow direction.

Page 24 of 32