maintenance training module 2 - tuthill pumptuthill confidential. • for all pumps, tightening of...

© Tuthill Corporation. All rights reserved. Tuthill confidential.

Maintenance Training Module 2 GlobalGear® with Cartridge Mechanical Seals


Topics in Maintenance Module 2 • Reassembly of Drive Module • Reinstall Drive Module • Adjusting End Clearance • Mechanical Seal Installation • Relief Valve Disassembly & Relief Valve

Troubleshooting • Servicing High Temperature Greased Bearing Units • Replacing Bushings • Lubrication Notes


• Reinstall the rotor into the bracket

Reassembly of the Drive Module


• Pick up external ball bearing



• Reinstall bearing into bearing carrier



• Reinstall inner bearing cap using fasteners



• Move cartridge mechanical seal into position

• Have flush ports in correct orientation

• Very loosely tighten gland nuts



• Reinstall bearing carrier



• Push rotor all the way in the bracket



• Insert lock washer with tabs

• If there is a bearing spacer, bearing spacer goes on first



• Install locknut



Reassembly of the Drive Module Locknut Torque Requirements

Nut Size Pump Size Newton-Meters

N-05 GG15-30 68 - 95

N-07 GG120-210 136 – 176

N-08 GG250 163 – 203

KM-12 GG550 163- 203


• Bend over tab of lock washer into slot on locknut



• Check and make sure that the gasket is in the correct position for flush

• Center of three holes at flush opening is correct

Reinstall Drive Module


• Gasket must align to allow flow through internal flush drilling size GG250 & smaller

• NPT plug indicates internal flush path at this location

Reinstall Drive Module


Reinstall Drive Module Position Drive Module Over Foot and Near Housing


Reinstall Drive Module Push Drive Module into Housing


Reinstall Drive Module Fasten Bolts Connecting Bracket to Housing


Reinstall Drive Module Fasten Bolts Connecting Bearing Carrier to Foot


• End clearance is distance between the rotor/idler end and the closest surface on the cover

Adjusting End Clearance


• Loosen set screws on rear cover

• Slowly and gradually tighten hex nuts on rear cover until rotor touches the pump cover



• When rotor is touching cover, there will be a slight drag when turning the shaft

Key in place



• Measure the gap between the end the end cover and the bearing carrier at four places 90° apart

• Make small adjustments to set screws and/or hex nuts so that the gap is the same at all four measured points



• Record the gap measurement with the rotor touching the cover

• This is zero end clearance



• Refer to TPC 254 for Tuthill recommended end clearance

• Add the value from TPC 254 to the gap measurement for zero clearance

• This will be the target gap measurement for end clearance setting



• Loosen hex bolts, several complete turns

• Tighten set screws on rear cover, enough to achieve the target gap measurement



• Make adjustments to set screws & hex nuts so that the measured gap is the same 4 points 90° apart

• Do final even tightening of the set screws/hex nuts & measure again to confirm the same measurements of the gap at 4 points 90° apart


Gap is the Same


• Final tightening of hex bolts to secure the rear cover in place



• If adjustment is being done in the shop, clearances can be measured directly from the open flanges



• After final tightening for end clearance, rotate the shaft by hand to confirm that the shaft rotates freely



• With cover removed, check clearance between rotor outer diameter and housing inner diameter at 4 points, 90° apart

Adjusting Radial Clearance


• Hex nuts can be adjusted to change radial rotor position

• Set screws may also need adjustment

Adjusting Radial Clearance


Final Tightening of Fasteners Recommend Using a Torque Wrench

Fastener Size Newton-meters

M6 8 – 12

M8 19 – 28

M10 41 – 54

M12 75 – 88


• For all pumps, tightening of the mechanical seal is the last step for reassembling pump

• Gland nuts should only be barely started tightened, and seal cartridge left loosely in place until the final seal tightening

Final Tightening of Mechanical Seals


• Mechanical seal has a limited travel range for self alignment, and it is best to reserve the travel range for end clearance adjustments done in the field



• Have flush ports in the correct position for piping

• Install the mechanical seal flush and square to the stuffing box

• Support the seal weight to center the seal cartridge on the shaft



• Tighten gland nuts in an even alternating pattern



• Tighten mechanical seal set screws in an even alternating pattern



• Remove fasteners securing the relief valve

Removal of the Relief Valve


• Relief valve and gasket removed

Removal of the Relief Valve


Disassembly of the Relief Valve


• Use large wrench to remove cap



• Relief valve cap removed



• Loosen jam nut using large wrench

• Remove bonnet using large wrench



• Bonnet removed



• Spring guide removed



• Remove spring



• Orange paint on spring indicates high pressure spring, range 10-17 bar for full bypass

• No orange bands indicates standard pressure range 3-10 bar for full bypass



• Remove poppet



Potential Problems with Relief Valves


• Poppet sealing edge and/or poppet seat not clean

• Result will be bypassing

• Corrective action is to clean the poppet and seat



• Relief valve chattering • Relief valve bypassing

flow • Cause is relief valve set

too low



• Correction is to increase the setting for full bypass pressure

• Higher pressure spring may be required



• Remove cap • Start pump • Slowly close discharge

valve completely • Read pressure gauge

on pump discharge • This is current full

bypass pressure setting

Setting Relief Valve in the Field


• Must know highest normal differential pressure

• Set relief valve to 50% higher than highest normal differential pressure



1. Loosen jam nut 2. Use adjusting nut to

set pressure on gauge to target setting


2. 1.


3. Once desired pressure setting is achieved, tighten jam nut

4. Replace cap

5. Open discharge valve


4. 3.


• Setting Relief Valve in the field should be accomplished in ten minutes or less

• Do not run the pump in full bypass for extended periods to avoid overheating



1. Hold relief valve inverted as shown

2. Drop in poppet, feet

down

Reassemble Relief Valve


3. Drop in spring 4. Drop in spring guide


4. 3.


• Holding relief valve inverted



• Reinstall bonnet using Teflon pipe dope on threads

• Reinstall cap using pipe dope on threads



• Remove bearing cover fasteners

Removing High Temp. Greased Bearings


• Greased bearings have a special bearing cover

• Greased bearings have a grease fitting



• Remove bearing cover

• Remove outer bearing cap hex nuts

• Remove outer bearing cap



• Remove inner bearing cap fasteners



• Push Back Inner Bearing Cap Toward Mechanical Seal Cartridge



• Greased bearings are shrunk onto the shaft for interference fit

• Must be pulled off with a bearing puller

• Best practice is not to reuse a bearing that has been pulled off a shaft


http://www.mactools.com/shoponline/product/tabid/120/p-319805-differential-bearing-puller.aspx


• Use recommended lubricant or equivalent

• Add grease to the grease fitting using a grease gun

Greasing High Temperature Bearings


• Old grease will come out here

• Old grease will slip under the lip seal

• Add new grease until a color change is observed with the old grease

Greasing High Temperature Bearings


• Can be pressed out with a hydraulic press

• Need to be pressed in with one forceful movement with no stops or hesitation

• Stopping mid way or hesitation may result in breaking the carbon bushing

Helpful Hint Carbon Bushings


• Tungsten Carbide Bushings can be pressed out with a hydraulic press

• Bracket or idler needs to be heated to 425° C before installing tungsten carbide bushings

• Safety provisions for handling hot materials required

Helpful Hint Tungsten Carbide Bushings


• Grease and oils designed to take years to break down

• Contaminants of moisture and particulate from dust and dirt degrade grease and oils

• Cleanliness is critical • Tips of grease guns need to be clean

Lubrication Helpful Hints


• Grease fittings should be cleaned before using • Work environment should be clean so as to avoid

introducing particulate into grease or oil • Use manufacturer recommend lubricants or cross-

over equivalents

Lubrication Helpful Hints


• Concept of predictive maintenance is to identify the need for equipment overhaul before a breakdown

• Planned maintenance is less expensive than responding to break-downs

• Planned maintenance has much less impact on potential loss of production or disruption to production schedules

Predictive Maintenance


• Significant increases from baseline recordings for temperature and/or vibration are indicators of coming maintenance requirements.

• Bearing temperature increases of 10 °C from baseline is an alarm level, 20 °C increase over baseline is an immediate action level.

• Vibration level increases by a factor of 2 above baseline is an alarm level, vibration increase of 2.5 times baseline is an immediate action level.

Predictive Maintenance How to know when maintenance is necessary?


• Record temperatures as degrees above ambient • Bearing temperature from the pump, gear

reducer, and motor

Predictive Maintenance Suggestion is to record monthly bearing temp. and vibration readings


Learn More About Tuthill Visit Our Websites www.tuthillpump.com www.tuthill.com

Like Us on Facebook

www.facebook.com/tuthillcorporation

Follow Us on Twitter @TuthillCorp


Excellence at work. Excellence in life.

maintenance training module 2 - tuthill pumptuthill confidential. • for all pumps, tightening of...

Documents