Machinery Components Maintenance And Repair Episode 1 Part 7 ppt

Once the baseplate has been filled with epoxy grout, the groutmust be completely cured before any machining is performed.. This covering shadingshould be erected 48 hours prior to alignm

Appendix 3-E

Specification and Installation of Pregrouted

Pump Baseplates

This appendix, or standard procedure, outlines the requirements for specifying and installing pregrouted machinery baseplates How-ever, this standard does not cover the installation requirements for machinery mounted on sole plates A typical application for this standard procedure would be the installation or retrofit of an ANSI

sur-By utilizing this standard procedure, baseplate-mounted ery can be installed with zero voids, eliminating the possibility ofexpensive field machining, and reducing field installation costs by 40

machin-to 50 percent

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II Specification of Pregrouted Baseplates

1 The underside of the baseplate to be pregrouted must be blasted to white metal to remove all existing paint, primer, orscale

sand-2 Any tapped bolt holes that penetrate through the top of thebaseplate, such as the coupling guard holding down bolts, must

be filled with the appropriate-sized bolts and coated with seize to create the necessary space for bolt installation aftergrouting of the baseplate

never-3 Anchor bolt or jack bolt holes, located inside the grouted space

of the baseplate, must have provisions for bolt penetrationthrough the baseplate after grouting

4 If the baseplate has grout holes and/or vent holes, these holesmust be completely sealed prior to grouting

5 All pregrouted baseplates will be filled with catalyzed epoxygrout or a premium nonshrink cement grout

6 Once the baseplate has been filled with epoxy grout, the groutmust be completely cured before any machining is performed

7 The machining of the baseplate must be set up to assure thatthe baseplate is under no stress or deformation

8 Prior to machining, the baseplate must be adjusted and leveled

to assure that no more than 0.020≤ of metal is removed at thelowest point

9 The baseplate will have two (2) mounting surfaces for thedriver, and two (2) to four (4) mounting surfaces for the drivenequipment The flatness tolerance for all these mounting sur-faces will be 0.001≤ per ft The finished surface roughness must

be no more than an 85P profiled surface

10 The two (2) mounting surfaces for the driver must be coplanarwithin 0.002≤ The two (2) to four (4) mounting surfaces forthe driven equipment must also be coplanar within 0.002≤ Theoriginal dimensional relationship (elevation) between the drivermounting surfaces and the driven mounting surfaces must bemaintained to within 0.020≤

11 Once the machining process has been completed, an machined” tolerance record must be taken, and provided withthe pregrouted baseplate

“as-III General Field Grouting Requirements

1 The epoxy grout utilized for the final field grout pour is a viscosity epoxy grout This grout has a special aggregate and has

low-Machinery Foundations and Grouting 141

the consistency of thin pancake batter This allows for a very thinfinal grout pour, with the optimum vertical thickness being 3/4≤.

2 All grout material components must be stored in a dry andweatherproof area in original unopened containers Under no circumstances should grouting components be stored outsidesubject to rain or under a tarpaulin with no air circulation

3 For optimum handling characteristics, precondition the resin andhardener to a temperature between 64° and 90°F

4 The work area, including foundation and machinery, must beprotected from direct sunlight and rain This covering (shading)should be erected 48 hours prior to alignment and grouting, andshall remain until 24 hours after placement of the grout, bywhich time the grout will have cured and returned to ambienttemperature The shading is also to prevent the foundation frombecoming wet It is important that the concrete remain dry prior

to grouting

5 Grouting shall be scheduled to take place during early morning

or afternoon hours depending on the surface temperatures

6 Just before starting the grouting operation, the temperature ofthe concrete foundation and machinery shall be taken using

a surface thermometer Ideal surface temperatures shall bebetween 70° and 90°F

IV Foundation Preparation

1 The concrete must be chipped to expose a minimum of 50percent aggregate so as to remove all laitance and provide arough surface for bonding Hand-chipping guns only will beused No jackhammers will be permitted If oil or grease arepresent, affected areas will be chipped out until free of oil orgrease

2 The concrete to be chipped should not extend more than

2≤ outside the “footprint” of the pregrouted baseplate viscosity epoxy grout can be poured only up to a 2≤ depth, andshould not extend more than 2≤ from the edge of the baseplate

Low-By limiting the chipped area of the concrete to just outside the foot print of the baseplate, simple forming techniques can be utilized

3 After chipping, the exposed surface must be blown free of dustand concrete chips using oil- and water-free compressed air from

an approved source Concrete surface can also be vacuumed

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4 After the foundation has been chipped and cleaned, adequateprecautions must be taken to ensure that there is no contamina-tion of the concrete surfaces To prevent debris, loose materials,

or parts from falling on the top of the concrete, properly coverthe workspace with polyethylene sheet

5 The foundation bolt threads must be protected during the ing operations

grout-6 As regards the bolts (Figure 3-E-l), which will be tensioned aftergrouting, care must be taken to prevent the bolt surfaces fromcoming in contact with the epoxy grout All anchor bolts shouldhave grout sleeves, which must be filled with a nonbondingmaterial to prevent the epoxy grout from filling the grout sleeve.This can be accomplished by protecting the anchor bolt before-hand between the top of the grout sleeve and the underside ofthe baseplate by wrapping the bolt with foam insulation, Dux-Seal, or other nonbonding material

Machinery Foundations and Grouting 143

Figure 3-E-1.

V Pregrouted Baseplate Preparation

1 Prior to positioning the baseplate over the foundation, the bottomside of the prefilled baseplate must be solvent washed to remove any oil or other contaminants from the surface After the surface has been cleaned, sand the surface to break the glaze of the epoxygrout

2 Vertical edges of the baseplate that come in contact with theepoxy grout must be radiused/chamfered to reduced stress con-centration in the grout

3 Vertical jackscrews should be provided at each anchor bolt Thejackscrews will be used to level the pregrouted baseplate Thesejackscrews will be removed after the low-viscosity epoxy cures,generally 24 hours after placement at 78°F

4 Leveling pads should be used under each jackscrew to preventthe baseplate from “walking” while leveling the baseplate Thepads will remain in the grout, and must be made from stainlesssteel The pads must have radius edges and rounded corners toreduce stress concentrations in the grout

5 With the jackscrews and leveling pads in place, level the grouted baseplate to 0.002≤/foot for API applications and 0.005≤/foot for ANSI applications

pre-6 After the baseplate has been leveled, the jackscrews must

be greased or wrapped with Dux-Seal to facilitate their moval once the grout has cured Wax is not a suitable releasingagent

re-VI Forming

1 Low-viscosity epoxy grout should only be poured up to a 2≤depth, and should not extend more than 2≤ from the edge of thebaseplate The optimum pour depth is 3/4≤ to 1≤ The best wood-forming material for this product is a “2 by 4”

2 Any wood surface coming in contact with epoxy grout shall becoated three times with paste floor wax (Liquid wax or oil is notacceptable as an alternative.) All forms must be waxed three

times before the forms are placed on the foundation Do not wax

the wood surface that comes in contact with the foundation This may prevent the silicone sealant from sticking to the form board, and forming a proper seal Care should be taken to

144 Machinery Component Maintenance and Repair

prevent any wax from falling on the concrete foundation or thebaseplate.

3 In most cases, there is very little room between the side of the baseplate and the edge of the foundation To help position the form boards, it is best to fasten the boards together with wood screws or nails One side of the form should leave an openingbetween the board and the baseplate that measures 1≤ to 2≤ The other three sides should have a separation of 1/2≤ to 3/4≤ The larger side will be used to pour the low-viscosity epoxygrout

4 Forms shall be made liquid tight Silicone sealant that does notcure to a hard consistency is best suited for this application Asealant that remains pliable will facilitate easy removal The bestapproach is to apply the sealant directly on the foundation, wherethe front edge of the form will fall, and then press the form down

to create the seal Check for cracks and openings between theform and the foundation, and apply additional sealant whereneeded Allow at least an hour for the sealant to cure beforepouring the grout

5 Because of the small depth of the epoxy grout pour, it will bevery difficult to use a chamfer stripe to create a bevel around theoutside of the form The best approach is to use a grinder afterthe grout has cure to create a bevel

6 Once the forms boards are in place, a small “head box” can bemade using blocks of duct seal To help create a slight head forthe grout, build a duct seal dam on the side of the baseplate withthe larger opening The dam should be about 3≤ tall, 12≤ long,and form a rectangle by connecting the two short sides direct tothe baseplate The end result will be a 3≤ head box that will beused to pour and place all the epoxy grout The best location forthe head box is the midpoint of the baseplate

VII Grouting Procedure for Low-Viscosity Epoxy Grout

1 The required number of units of epoxy grout, including lated surplus, should be laid out close to the grouting location.The 1/2≤ drill and mixer blade should be prepared for the groutingoperation

calcu-2 Low-viscosity epoxy grout is a three-component, high-strength,

100 percent solids epoxy grouting compound The resin,

hard-Machinery Foundations and Grouting 145

ener, and aggregate are supplied in a 6-gallon mixing container.One unit produces 0.34 cubic feet of grout.

Inspection of Work Site

Check for:

• Proper shading

• Preparation of concrete, baseplate, jackscrews, leveling pads

• Wood forms properly waxed and sealed

• Foundation bolts wrapped and sealed

Before Mixing

Check for:

• Mixing equipment clean

• Surface temperature of epoxy grout components (<90°F)

• Ambient temperature (<95°F)

While Mixing

Check for:

• Slow drill motor rpm’s to avoid entrapping air

• Resin and hardener mixed 3 minutes (use the timer)

Before Pouring

Check for:

• Temperature of concrete foundation (<95°F)

• Temperature of the machinery baseplate (<95°F)

• Ambient temperature for the record

• Maintaining head until the grout starts to set

146 Machinery Component Maintenance and Repair

Check for:

• Work site kept shaded for 24 hours to avoid sharp temperatureincrease

• Formwork left in place until grout is no longer tacky to the touch

Machinery Foundations and Grouting 147

Chapter 4

Process Machinery Piping*

Fundamentals of Piping Design Criteria

It is certainly not within the scope of this text to deal extensively withpiping design and installation criteria; however, there are certain funda-mentals which can have an impact on machinery reliability These must

be appreciated by the machinery engineer if he is to retain a good overview

of the integrated machinery system Some key installation procedures andverification criteria are, therefore, included for the machinery engineer’sbenefit

The design of a piping system consists of the design of pipe, flanges,bolting, gaskets, valves, fittings, and other pressure components such as

expansion joints It also includes pipe supporting elements but does not

include the actual support structures such as building steel work, chions or foundations, etc

stan-Piping Design Procedure

These steps need to be completed in the design of any piping system:

• Selection of pipe materials

• Calculation of minimum pipe wall thickness for design temperaturesand pressures (generally per ANSI B31.3)

• Establishment of acceptable layout between terminal points for thepipe

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* We gratefully acknowledge the help received from Wolfgang Schmidt (formerly with Essochem Europe Brussels, Belgium), in compiling this section.

• Establishment of acceptable support configuration for the system

• Flexibility stress analysis for the system to satisfy the design criteriastipulated by ANSI B31.3

This flexibility analysis is intended to verify that piping stresses, localcomponent stresses and forces/moments generated at the terminal pointsare within the acceptable limits throughout all anticipated phases ofnormal and abnormal operation of the plant during its life

Design Considerations

A piping system constitutes an irregular space frame into which strainand attendant stress may be introduced by initial fabrication and erection,and also may exist due to various circumstances during operation.Example: three pumps taking suction from and/or discharging into acommon header, as shown in Figure 4-1 One or two of the three pumpsremoved for shop repair

Each piping system must be designed with due consideration to thesecircumstances for the most severe conditions of coincident loading Thefollowing summarizes possible imposed loads that typically need to beconsidered in a piping design:

Process Machinery Piping 149

Figure 4-1 Flexibility analysis must consider:

• All pumps operating simultaneously

• Effect of any pump used as nonrunning standby spare, or blocked off for maintenance.

Design Pressure Loads

The pressure at the most severe condition of coincident internal orexternal pressure and temperature expected during normal operation

Weight Loads

• Dead weight loads including pipe components, insulation, etc

• Live weight loads imposed by service or test fluid, snow and ice, etc

Dynamic Loads

• Design wind loads exerted on exposed piping systems

• Earthquake loads must be considered for piping systems where

earthquake probability is significant

• Impact or surge loads typically due to water hammer, letdown, or

discharge of fluids

• Excessive vibration arising from pressure pulsations, resonance

caused by machinery excitations or wind loads

Thermal Expansion/Contraction Effects

• Thermal and friction loads due to restraints preventing free thermalexpansion

• Loading due to severe temperature gradients or difference in sion characteristics

expan-Effects of Support, Anchor, and Terminal Movements

• Thermal expansion of equipment

• Settlement of equipment foundations and/or piping supports

The When, Who, What, and How of Removing Spring Hanger Stops

Associated with Machinery Initial Tasks Prior to Machinery Commissioning

• Align machinery without pipe attached

• Adjust pipe for proper fit-up and make connection

150 Machinery Component Maintenance and Repair

• Observe alignment of machinery with pipe being attached If excessive movement is noted, the pipe is to be disconnected and modified until misalignment is brought within the limits permitted.

• If the pipe is greater than 8 in NPS, one may need to add sandbags

or similar weights to the pipe at the hanger adjacent to machinery tosimulate the operating condition of the pipe

• Pull stops on all system hangers

• Check to determine that no hanger travel indicator moves out of the

“1/3total travel” cold setting zone If travel is excessive, refer diately to the design contractor for modifications of support

imme-• Adjust the hanger to return travel marker to the “C” position

• Record alignment of machinery

• Reinstall piping system hanger stops

Final Check, Immediately Prior to Machinery Operation

• Disconnect or dismantle piping as necessary

• Flush and/or steam blow

• Repipe and realign

• Weight the hanger adjacent to the machinery

• Pull system pins, check “C” settings and fine tune hangers If travel

is excessive (out of the 1/3 total “C” zone) contact the designatedpiping engineer for resolution

Flange Jointing Practices

These steps can be written up in checklist format allowing field sonnel to use piping-related guidelines in an efficient manner, as shown

per-in the appendices at the end of this chapter

The importance of getting flanged joints right the first time cannot beoveremphasized if trouble-free performance during startup is desired Inorder to obtain an adequate joint the first time we must assure ourselvesthat the contractor, subcontractor, and the working crews appreciate theimportance of quality workmanship needed during each stage of the flangejoint building process This includes materials handling and storage oper-ations, piping prefabrication, erection, and bolting-up procedures Timespent in covering preventive measures, supervision and crew guidance,and/or training (if needed), and assuring adequate quality control will paydividends

Process Machinery Piping 151