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®. 18-3/4” 15,000 psi Conventional Ram Blowout Preventer. Blowout Preventer (BOP).
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® 18-3/4” 15,000 psiConventional RamBlowout Preventer
Blowout Preventer (BOP) The equipment (or valve) installed at the wellhead to contain wellbore pressure either in the annular space between the casing and the tubulars or in an open hole during drilling, completion, testing,or workover operations. Ram Blowout Preventer A valve that uses metal blocks with integral elastomer seals to seal off pressure on a wellbore with or without tubulars in the bore.
18-3/4 - 15,000 Ram BOP • Field replaceable seal seat for long service life and easy field repair • Multiple position locking (MPL) automatically locks rams in a seal-off position • BOP can be equippedwith blind shear,variable, pipe or casingrams for ultimate wellcontrol flexibility • Cylinder liners field replaceable • Hinged bonnets for ease of ram access • Fluid hinges removable for rapid simple seal replacement • One piece piston rod for strength and durability
18-3/4 15,000 Ram BOP • Bonnet bolts sized and arranged for reliable bonnet seal operation and proper bonnet stress distribution • Side outlets • Availablepressureenergized bonnetseal conversion • Stainless steel linedring grooves forcorrosion resistance • Piston seals pressure energizedlip seal for reliable seal operation
OperationHydraulic Circuit • Application of hydraulic pressure to the operating cylinders pushes the pistons inward or outward to close or open the rams • The multiple position lock is an automaticlock, locking the rams in place after theyare closed hydraulically • Operating chambers are ratedfor 3000 psi continuousoperation and have beentested to 4500 psi • Hydraulic closing pressuresfrom 100 psi to 300 psi indicate satisfactory operation
OperationHydraulic Circuit (continued) • Hydraulic pressure applied to closing port initiates fluid flow in drilled passages in the BOP body • Fluid flows from the body through the fluid hinge to the bonnet hinge • Fluid then flows from the bonnet hinge through a drilled passage in the bonnet and exits between the cylinder and cylinder liner
OperationHydraulic Circuit (continued) • Fluid then acts on the backside of the rams closing them • Fluid from the opening sides is pushedout the porting in the bonnet • Fluid flows through a drilledpassage in bonnet and intothe bonnet hinge • Fluid then passes throughthe seal sub in the fluidhinge, through the drilled passage in the preventer body and out through the opening chamber port
Multiple Position Lock (MPL) • Opening and closing controlled byuni-directional clutch mechanism,lock (overhauling) nut andlock (overhauling) screw • The clutch mechanismmaintains nut and ram inlocked position • The clutch is disengagedby hydraulic pressureto open the ram
Multiple Position Lock (MPL)(continued) How the MPL Works • Tail rod contains two types of threads • One end - standard LH Acme thread • Other end - fast lead 6-path helical thread • Mating nut fitted to the tail rod • Nut contained by two thrust bearingspermitting rotation but preventing linear travel • Linear motion of the tail rod during closingor opening causes nut to rotate • Fast lead, 6-path helical thread rotates thenut three turns per foot of travel
Multiple Position Lock (MPL)(continued) How the MPL Works • Rear clutch plate and front clutch • Contact of rear clutch plate to front clutch platemaintained by spring force • Rotation in the opening direction prevented byinterlocking teeth • Sloped angle of teeth permits rotation in closing direction • Hydraulic opening pressure acts on the cylinderliner to release locking mechanism • Cylinder liner moves back against transfer ring • Transfer ring bears on the rear clutch platedisengaging it from the front clutch plate • Opening pressure on the piston moves the ramto the open position as the lock nut and front clutch plate rotate freely
Multiple Position Lock (MPL)(continued) How the MPL Works • The front clutch plate is bolted to the lock(overhauling) nut. • Four rectangular keys in the rear clutch plateengage slots in the retainer plate • Allows linear motion and prevents rotational motionof the rear clutch plate • Springs are captured between rear clutch plate and retainer plate • Opening forces on the piston rod held in check by thelock nut • Opening force creates torque in the lock nut • Torque is transmitted through the engaged teeth of front and rear clutch plates • The rear clutch plate is keyed to the retainer plate • The retainer plate is pinned to the cylinder head thus preventing rotation and locking the assembly
Multiple Position Lock (MPL)(continued) How the MPL Works • Application of hydraulicopening pressure permitsrams to open • Hydraulic pressure acting onthe cylinder liner moves it backto disengage the clutch • Continued application ofopening pressure maintainsthe clutch unlocked and opensthe rams
Multiple Position Lock (MPL)(continued) How the MPL Works • Provision for testing MPL • Two lockout devices • Prevent cylinder liner from disengaging clutch • Opening pressure simulates opening forces applied to the ram • Visual indication of position of lockouts provided
Engineering Data (continued) + Using Hydril BOP Thread Lubricant * using light machine oil
Engineering Data (continued) 18-3/4 - 15,000 Hydril Clamp Pressure-Tension-Bending Capability • Hydril clamp designed in accordance with procedures described in “Summary of Design Equations for Clamp Type Connectors” (1978 Rev.)
Engineering Data (continued) 18-3/4 - 15,000 PSI API Flange Pressure-Tension-Bending • API flange capability calculated by a modified formula given in Appendix H of API Spec. for Wellhead Equipment 6A, Mar. 1983.
Packers and SealsFixed Bore Pipe Rams • Separate front packer and top seal • Top seal feedable rubber energized duringfinal seal off portion of the ram stroke • Front packer has large volume of feedable rubber bonded to heavy anti-extrusion plates for repeated closures and pressure cycles • Hy-temp front packers and top seals available • Hy-temp seals require the ram block be modified for their use • Hy-temp front packers are secured to the ram block by bolts
Packers & Seals (continued) Ram Change Procedures 1. Open (retract) the rams by applying opening pressure 2. Disengage all bonnet bolts 3. Manually swing both bonnets open and clear of BOP stack. Application of closing pressure to force open bonnet will damage piston rod(If the blowout preventer is not flanged to a wellhead or test stump, unbolt and open only one bonnet at a time to prevent blowout preventer from tipping over.) 4. Extend the rams by applying closing pressure 5. Remove the ram assembly by attaching an eyebolt in the hole provided and lift straight up 6. Replace with new rams and remove lifting eye 7. Retract ram back into bonnet compartment by applying opening pressure 8. Inspect bonnet seal and seal area, lube with a light weight oil 9. Clean and lubricate bonnet bolts with Hydril BOP thread lubricant 10. Manually swing bonnets closed and insert bolts 11. Hand tighten bolts starting with number one bolt, snugging bonnet to body. Then torque all bolts to 8500 ft-lbs*.Torque bolts beginning with the middle bolt on the off-hinge side, then the middle bolt on the hinge side. All other bolts may be torqued in any sequence. * Other lubricants require different torque values.
Packers & Seals (continued) Fixed Bore Pipe Rams Front Packer & Top Seal Change-out Standard Front Packers & Top Seals 1. Insert screwdriver between upper seal and frontpacker and pry up to remove upper seal fromits groove 2. Insert two screwdrivers, one on either side of thefront packer and work the packer out Hy-Temp Front Packers and Top Seal 1. Remove top seal by inserting screw drive betweenupper seal and front packer 2. Remove two cotter pins from back of ram 3. Remove screws from packer 4. Remove packer
Packers & Seals (continued) Fixed Bore Pipe Rams Front Packer & Top Seal Change-out (continued) Regular Packers & Top Seal 1. Insert packer into ram until seated 2. Fit top seal in groove pins down Hy-Temp Packers & Top Seal 1. Insert packer into ram until seated 2. Bolt packer in with two bolts 3. Insert cotter pins 4. Fit top seal in its groove
Packers & Seals (continued) Shear Rams • Designed to shear drill pipe and seal off the wellbore • May be used as blind ramsto seal off the open hole • Shear blade design minimizesrequired shearing load • Dual V arrangementconcentrates deformingforces so drill pipe is crimpedon the shearing plane • Sharp rake angles imposeadditional tensile load to aid in pipe separation • After shearing lateral T-seal seals on the horizontal sealing surface of the lower blade carrier
Packers & Seals (continued) Shear Ram Assembly Lower Blade Shear Ram 1. Remove lower blade top seal 2. Remove the two lower blade cap screws and the lower blade 3. Remove the two anti-extrusion blocks Upper Blade Shear Ram 1. Remove the two alignment pin setscrews 2. Remove the two alignment pinswith a common screw driver 3. Remove the three upper blade setscrews from the top of the block 4. Remove the four upper blade capscrews retaining the upper blade 5. Remove the upper blade 6. Remove the lateral T-Seal 7. Remove the upper blade top seal 8. Inspect all parts for wear and replace as required
Packers & Seals (continued) Shear Ram Assembly Lower Blade Shear Ram 1. Prior to assembly, visually inspect all parts, apply a coating of non-petroleum based oil such as castor oil to all seals and seal grooves, and lubricate all threads with Hydril thread lubricant 2. Install the lower blade on the ram block with the lowerblade cap screws 3. Install the two anti-extrusion blocks into the groovesof the ram block 4. Install the lower blade top seal in the upper sealgroove of the ram block Upper Blade Shear Ram 1. Prior to assembly, visually inspect all parts, apply acoating of non-petroleum based oil such as castoroil to all seals and seal grooves, and lubricate allthreads with Hydril thread lubricant 2. Install the upper blade top seal into the upper sealgroove of the ram block 3. Install the lateral T-seal. Insure that the lower T-sectionof the seal is properly fitted within its groove 4. Install the upper blade with the four upper blade capscrews hand tight. Insure that the lateral T-seal isproperly fitted between the upper blade and the ram block. Torque the cap screws. 5. Install the three upper blade set screws into the top of the ram block. Torque the set screws 6. Install the two alignment pins and hand tighten snug with a common screw driver 7. Install the two alignment pin set screws and tighten snug
Packers & Seals (continued) Hydril Variable Rams (HVR) • Designed to seal on a range of pipediameters3-1/2” - 5-1/2”- 31168334-1/2” - 7” - 3118844 • Interlocking I-beam inserts molded intothe rubber • They confine the rubber within the packerand against the pipe to preventextrusion of the sealing element • Top seal has large volume of feedablerubber for long and dependable service life • Interchangeable with fixed rams or casing rams
Packers & Seals (continued) Hydril Variable Ram Disassembly 1. Remove top seal 2. Remove two cotter pins 3. Remove two bolts 4. Remove front packer Assembly 1. Insert front packer 2. Screw in bolts 3. Insert cotter pins 4. Insert top seal
Packers & Seals (continued) Replaceable Upper Seal Seat Replaceable Metal Seat • Provides seal surfacefor the ram top seal • Lock ring energized by16 specially coatedsocket head set screwsto retain the seat • Contains one seal and backup ring
Packers & Seals (continued) Bonnet Seals • Bonnet hinge seal • Bonnet sealMay be converted tolow-torque bonnetseal configuration • Piston rod mud seal • Bonnet to pistonrod seal
Packers & Seals (continued) Cylinder Seals • Cylinder liner to bonnet seal - O-ring • Cylinder to bonnet seal O-ring • Piston seal - 3-piece bi-directional seal • Cylinder head seal • Cylinder head dirt seal • Lockout stem seal
Packers & Seals (continued) Hinge Pin Seals • Hinge pin seal -O-ring • Hinge pin threadseal - O-ring • Hinge pin bearing seal -O-ring
Packers & Seals (continued) Fluid Hinge Seals • Fluid hinge to bonnethinge seals O-ring • Fluid hinge tobody sealsO-rings • Sub to bonnet hingeseals O-rings • Sub to energizerseals O-rings • Energizer to fluidhinge seals -O-rings withbackup rings
Maintenance • Visually inspect the body and ring grooves • Check all bolting • Check ring gaskets • Visually inspect • Bonnet seal areas • Bonnet seal grooves • Ram bores • Seal seats • Piston rods • Visually inspect • Ram blocks • Front packers • Top seals • Bonnet seals
Maintenance (continued) • Once a year inspect • MPL bearings • BOP seal seat torails (ram cavity floor) • Minimum ram height • Maximum ramcompartment height
Testing • Hydraulically test with clear water • Inspect all hydraulic connections • Set appropriate size test tool in test stump • Close pipe rams on appropriate size pipe. Check for hydraulic leaks • Increase wellbore pressureto test pressure required • Low pressure • High pressure • Check for leaks • Continue test until rams are tested • Unless you intend to ruin your testmandrel, DO NOT test shear ramswith pipe in the hole
Testing (continued) • Lockout devices are manually operated and require either a 3/8” square drive or a 5/16” 12-point socket wrench • Close rams, visually check for leaks and reduce closing pressure to 100 psi • Check freedom of movement of lockout devices by alternately turning them clockwise then counter-clockwise about seven turns • Engage lockout devices. Rotate stem seven turns clockwise until snug • Bleed closing pressure to 0 psi • Apply opening pressure to 1500 psi in 500 psi increments, hold for three minutes. Check for leaks Visually observe rams for movement.
Testing (continued) MPL Lockout Test • Reduce opening pressure to 0 psi • Apply 100 psi closing pressure • Disengage lockout devices by rotating stems counter clockwise about seven turns until snug • Gradually increase opening pressure from 0 until rams open
Disassembly MPL Cylinder Disassembly • Standard mechanics toolsrequired • Remove rams • Close bonnets and snugup to the two center bolts • Apply opening pressure • Install 1” lifting eye incylinder head (154) andsupport with a hoist • Remove ten cylinderhead cap screws (156)and remove cylinder head • The cylinder head seal (155), dirt seal (152), and rear lock nut bearing are now accessible
Disassembly (continued) MPL Cylinder Disassembly (continued) • Remove lock nut clutchassembly by rotating thelocating pin (158)counterclockwise.Identify it with itsrespective lockscrew (144) • Place clutch assemblyon a work bench • Remove eight screws(147) holding the frontclutch plate (146) to lock nut (143). As the screws are removed, the rear clutch plate (148) will be pushed toward the front clutch plate (146) by the springs (150).
Disassembly (continued) MPL Cylinder Disassembly (continued) • Remove the frontclutch plate (146), therear clutch plate (148),its keys (151) and keykeeper (167) from locknut (143) • Remove the retainerplate (145) from thelock nut (143) • The front lock nutbearing (149) may beremoved from thelock nut
Disassembly (continued) MPL Cylinder Disassembly (continued) • Support the cylinder (137) using a choker sling between the flange and the MPL lockout devices. Remove the twelve cylinder nuts (142) and slide the cylinder back over the piston and cylinder liner • The cylinder seal (133) andbackup ring (166) are now exposed • The transfer ring (164) shouldbe removed from inside the cylinder • Remove both lockout glands(160) from the cylinder byrotating counterclockwise • Separate the lockout segments(161) from the lockout stems (159)by rotating the stems clockwise (left handed threads) with the MPLlockout wrench (3/8” square drive) • The lockout stem seals (162) and backup rings (163) are now exposed
25 10 12 29 28 31 30 40 11 39 35 36 24 22 32 37 38 27 21 23 Disassembly (continued) Fluid Hinge Disassembly • The fluid hinge and bonnet hingescontain all of the seals concernedwith the transfer of hydraulic fluidfrom the body to the bonnet andthe bonnet to the body • Reduce all operating pressuresto zero • Remove the two hex head capscrews (36) by counterclockwiserotation • Slip the fluid hinge (24) assemblyfrom between the bonnet hinges.As the fluid hinge assemblycomes away from the body watchfor the two fluid hinge to bodyO-rings (35)to preventlosing them • The seal sub assemblies contained in the fluid hinge are spring loaded. • Separate the seal sub (25) and seal sub energizer (27) by pulling them apart
52 54 59 58 55 56 57 53 75 74 63 60 141 62 61 Disassembly (continued) Bonnet Removal • Insert two eyebolts in the toptwo holes of the bonnetNOTE: These holes are forlifting the bonnet assemblyonly and not the entire BOP. • Attach a chain sling tosupport the bonnet weight,disengage all bonnet bolts,and remove the two hingepins (61) by rotating fromthe load hinges. The hingepin thread and bearingseals (62 and 63) are nowexposed. • Remove the four bonnet hinge cap screws (73) from each bonnet hinge. Slide the bonnet out off the location pins (75). The bonnet hinge O-ring (74) is now exposed.
25 10 12 29 28 31 30 40 11 39 35 36 24 22 32 37 38 27 21 23 Disassembly (continued) Bonnet Disassembly • The load hinge thrust (38) andradial (37) bearings are removed byunscrewing the four load hingecap screws. • The hydraulic connections (10) areremoved by unscrewing the fourcap screws (12). The hydraulicconnection O-ring is now exposed.
Disassembly (continued) Upper Seal Seat Removal • Open both bonnets • Remove sixteen socket head set screws(5/16” hex key) • Seat should be free to be lowered fromits pocket • Caution! Have the seat blocked from belowto prevent injury should the seat drop
25 10 12 29 28 31 30 40 11 39 35 36 24 22 32 37 38 27 21 23 Assembly (continued) Load Hinge Installation • The upper load hinge (21) is installedwith the hinge pin bearing seat up.It is fitted over the two locatingpins (22) pressed in the body. • The lower load hinge (2) is installedover two locater pins (22) with thehinge pin bearing seat down. • Install the four load hinge capscrews (23) on each hinge andtighten by clockwise rotation • Install the hinge pin thrustbearing (38) • Install the hinge pin radialbearing (37)
Lock Ring 5 6 7 9 Seal Seat 4 Assembly (continued) Upper Seal Seat Installation • Fit the lower seat to body O-ring (6) andbackup ring (7) to the seal seat (4) • Fit the lock ring (5) over the barrel of the sealseat (4) and seat it in its groove • Screw in sixteen set screws (9) until they just touch the lock ring (5) • Fit the seat into the body, blocking it up inplace • Engage the sixteen set screws (9) startingwith one adjacent to the split in the lock (5),then work around the seat (4) expandingthe lock ring into its groove in the body
52 74 73 72 71 Assembly (continued) • Check machine finishes on bonnet (52) and bonnet hinge (71) or 72) for smooth surfaces • Install O-ring (74) to finish machine side of bonnet hinge (71 or 72) (Lubricate O-ring) • Attach bonnet hinge (71 or 72) to end of bonnet (52) with four bonnet hinge cap screws (73)
Assembly (continued) Bonnet Assembly Installation • Install two lift eyes in bonnet • Install lift sling • Install bonnet onto BOP aligning thebonnet hinge with the load hinges • Install the upper and lower hinge pins • Position the bonnet vertically by hingepin adjustment • Raise by loosening the lower hinge pinand tightening the upper hinge pin • Lower by loosening the upper hinge pinand tightening the lower hinge pin • Over-tightening may bind thrust washers • Bonnet position is correct when the guide pin on the bonnet enters the hole in the body smoothly • Install bonnet bolts and seals
Assembly (continued) Fluid Hinge Installation • Insert the seal sub into thesub-energizer • Insert springs into fluid hinge • Insert Seal sub/subenergizersinto fluid hinge • Install fluid hinge to bodyO-rings • Fit fluid hinge between bonnethinges • Fit washers over hex head cap screws and insert cap screws into fluid hinge • Torque cap screws to 250 ft-lbs