grlc grayloc installation maintenance bulletin rev j

7/26/2019 GRLC Grayloc Installation Maintenance Bulletin Rev J

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Installation and Maintenance of the GraylocConnector

General Information

The Grayloc connector provides a highlyreliable metal-to-metal seal that is both self-energized and pressure-energized. A completeGrayloc connector consists of two hubs, oneseal ring, one set of clamps, stud bolts, andspherical-faced nuts.

Assembly and maintenance are easy. Sealrings are designed to be reusable and usuallyonly one connector size is necessary for eachpipe size.

The Grayloc hub designation (e.g. 2 GR20 forindustrial or B20 for oilfield applications)identifies the appropriate clamp by the firstnumber or letter (2 or B) and the appropriateseal ring by the second number (20).

Grayloc hubs are furnished with hub protectorsthat should be removed only when the hubsare being welded in place, stress relieved, orwhen the connection is being assembled.

Fabrication

Grayloc hubs may be fabricated to piping orother component equipment by establishedwelding procedures. Initial fit-up and alignmenttolerances normally used in the fabrication of

ANSI flanges are also acceptable for the

Grayloc hub. During welding, care should betaken to protect the hub sealing surfaces fromdamage such as scratching and weld spatter.

When required, stress relieving of carbon andlow alloy steel hubs should be done incompliance with applicable industry codes andrequirements. Hub sealing surfaces must beclean prior to being placed in the furnace.

Engineering, Manufacturing and Sales Locations :

Western Hemisphere Eastern HemisphereGrayloc Products, L.L.C.9342 Telge RoadHouston, Texas 77095U.S.A.Tel: 713-466-8853

Fax: 713-937-2335

Grayloc Products Canada Ltd.837 Fourth LineOakville, Ontario L6L 5B8CanadaTel: 905-842-3150

Fax: 905-842-1785

Grayloc Products Ltd.Hydropark, Tern PlaceDenmore Road, Bridge of DonAberdeen, Scotland AB23 8JXTel: (44) 1224 222790

Fax: (44) 1224 222780

Grayloc Products M.E.Unit No FZS1-BG04Jebel Ali Free ZoneDubai, U.A.E.Tel +971 (0) 4 886 1980

Fax +971 (0) 4 886 1766


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Proper assembly of the Grayloc connector is the key

to pressure containment of the connection.

Before Assembly

The Grayloc seal ring does not seatuntil the connection is fully tightened;

therefore, a small clearance, orstandoff, between the seal ring rib andhub face should be observed when theseal ring is placed into a mating hub. Ifno standoff is present, use a new sealring.

FREE POSITION

Clean all lubricants and foreign matterfrom the hub sealing surfaces beforeinstallation. Use a non-abrasivematerial to clean the seal rings of allforeign matter. Normally, all seal ringshave a coating or plating (PTFE,

MoS2 with Graphite), whichacts as alubricant during make-up. In someapplications where uncoated /

unplated seal rings are used, a lightfilm of clean lubricant isrecommended.

When applying lubricant, take specialcare to ensure that no solid orforeign particles are present in thelubricant. Also take care to preventmechanical damage to the seal ringand the hub sealing surfaces.

Before assembly, the hubs must bealigned to allow engagement of the

seal ring lips to the hub sealingsurfaces. This will ensure properengagement of the hub and clampsegments. For misaligned systems, itmay be necessary to apply externalloads to the mating piping (using

jacks, come-a-longs, etc.) to alignthe hubs prior to assembly.

Assembly

1. Align the hubs so that the sealring can be installed.

2. Install the seal ring in thesealing surface of the hubs.The seal ring should rockslightly; i.e., the seal ring ribshould not be able to fullycontact the hub face. If it doesnot rock, use a new seal ring.

3. Apply lubrication to the hub-clamp contact area to reducefriction during assembly.Position the clamps around the

hubs.

4. Lubrication of the bolting, thespherical faces of the nuts andclamp ears is recommended.Insert the stud bolts into thebolt holes of the clamp ears.The stud-bolts should beinstalled to insure that thespherically faced nuts fit intothe spherical seats of theclamp ears.

Clamp

EarBlind Hub

Seal RingRib

Relief Groove

SphericalFaced Nut

Clamp Spacing

Al l-Thread Stud

Clamp

Blind Hub

Butt Weld Hub

Grayloc SealRing

HubFace

SealingSurface

SealingSurface

Seal RingRib

SealingSurface


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Proper assembly of the Grayloc connector is the key

to pressure containment of the connection.

After proper assembly, the hubfaces will fully contact seal ring rib.

MAKE-UP POSITION

For extreme misalignment and / orextreme piping loads, torque values1-1/2 to 2 times the table values are

recommended. Do not exceed 2times the recommended torquevalues, as this may result inpermanent damage from distortionto the connector components.

5. Tighten the bolting in a criss-crosspattern (i.e., bolt #1, #3, #2, #4),while keeping the spacing betweenthe clamp halves approximately

equal.

6. Torque the bolting to therecommended values shown in thisbulletin. The clamp should be jarred(i.e. a sound blow to the back of theclamp with a soft hammer) and thebolting retightened. This should berepeated until bolt torque does notchange after jarring (torque, jar,torque, jar, etc).

Butt Weld Hubs

SphericalFaced Nuts

Al l-ThreadStuds

Metal Seal Ring

2 Piece ClampSegments

Seal Ring

Rib


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Disassembly

Vent and verify that all pressurehas been removed from the linebefore disassembling the Graylocconnector. The nuts should not becompletely removed from the studsduring the initial disassembly of theclamp. Loosen the bolting and allclamp segments to allow the safe

release of any trapped pressure.Ifthe clamp segments remain inplace around the hubs, then bothclamp segments must be loosenedby jarring (i.e. a sound blow to theinside of the clamp ear with a softhammer). The bolting can then besafely removed after release of anytrapped pressure.

Maintenance

Special maintenance is not

required for a Grayloc connector

that has been properly assembled.

However, when disassembling aconnector, check the seal ring forstandoff prior to reassembly andvisually inspect the hub seats foruniformity and freedom from burrsand deep scratches. These

irregularities on seal surfacescould cause leakage.

Remove scale, rust, burrs or deepscratches from hub seal surfacesby lightly polishing with fine steelwool or crocus cloth around theseat. To insure uniform blending ofre-worked surfaces, polish aroundthe seat circumferences.

Never lap the hub seal surfaceswith a seal ring; this practice willdamage both the seal ring and hub

seal surface and prevent aneffective seal.

The connector should not betightened while under pressureloading or severe mechanicalloads. Consult Grayloc Productsprior to any welding on a Graylocclamp or seal ring.

All components of the Graylocassembly should be obtained onlyfrom Grayloc Products or one of itauthorized licensees. Theperformance and reliability ofGrayloc connectors can beassured only when Grayloccomponents are used. A completeGrayloc Products Catalog isavailable upon request.

Stud BoltSize Stud Bolt Length (Inches)

ClampSize

Average Torque

Nut Size(Across Flats) ft-lbs Nm

1/2-13 UNC-2 3 7/8 1 17 23

5/8-11 UNC-2 5 1-1/16 1 35 48

3/4-10 UNC-2 5, 6 1-1/4 2, 2-3 55 75

7/8-9 UNC-2 7, 6 1-7/16 4, C, B 90 122

1-8 UNC-2 8 1-5/8 5, D, E 140 190

1-1/8-8 UN-2 93/8 1-13/16 6, F 205 279

1-1/4-8 UN-2 10 2 8 290 394

1-1/8-8 UN-2 11 1-13/16 XF 330 449

1-3/8-8 UN-2 11 2-3/16 X8, G, XG 390 530

1-5/8-8 UN-2 14, 141/8, 17 2-9/16 H, 10H, X14 630 857

1-3/4-8 UN-2 16, 19 2-3/4 X10H, 12M, X16 870 1,183

1-7/8-8 UN-2 21 2-15/16 X18 1,170 1,591

2-8 UN-2 16, 18, 24 3-1/8 P, 2P, X12M, X20 1,300 1,768

2-1/4-8 UN-2 27, 20, 24 3-1/2 X24, 30, 3V 1,870 2,543

2-1/2 UN-2 22, 31, 29, 203-7/8

S, U, 32, 36, 3W, 5P 2,5703,495

2-3/4 -8 UN-2 28 4-1/4 Y 3,500 4,760

3-8 UN-2 41 4-5/8 Z 5,100 6,915

3-1/4-8 UN-2 35 5 2Y, 40 7,100 9,656

Average Torque Values For Two-Piece, Four-Bolt GraylocClamps*

Copyright 2004 by Grayloc

Products. All Right Reserved. GLOC-106 Rev. J / 6-05

Engineering, Manufacturing and Sales Locations :

Western Hemisphere Eastern HemisphereGrayloc Products, L.L.C.9342 Telge RoadHouston, Texas 77095U.S.A.Tel: 713-466-8853Fax: 713-937-2335

Grayloc Products Canada Ltd.837 Fourth LineOakville, Ontario L6L 5B8CanadaTel: 905-842-3150Fax: 905-842-1785

Grayloc Products Ltd.Hydropark, Tern PlaceDenmore Road, Bridge of DonAberdeen, Scotland AB23 8JXTel: (44) 1224 222790Fax: (44) 1224 222780

Grayloc Products M.E.Unit No FZS1-BG04Jebel Ali Free ZoneDubai, U.A.E.Tel +971 (0) 4 886 1980Fax +971 (0) 4 886 1766

grlc grayloc installation maintenance bulletin rev j

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