cementing equip

8/21/2019 Cementing Equip

http://slidepdf.com/reader/full/cementing-equip 1/12

Cementing Services and Products ■ Equipment 77

IntroductionCementing requires specially designed equipment. Equipment may be high-powered like theCPF-376 double-pump cement trailer or CPT-372 double-pump cement truck or highly versatileto accomplish numerous cementing operations each day, like the CemSTREAK cementing unit.Even more specialized equipment is required for use offshore, with the skids designed to deliverhigh power with high reliability. In many cases, offshore cementing is done using liquid additivesand LAS* liquid additive systems are used for precise delivery of the additives to the mixing sys-tem. When subsea heads are used, the DeepSea EXPRESS plug launching system is used for reli-able wiper plug launching. Monitoring and recording of the cementing operation is done usingthe CemCAT computer-aided treatment software and a portable computer. Innovative mixingcontrol is accomplished using the SFM* Solids Fraction Monitor.

CemSTREAK land cementing unitThe CemSTREAK land cementing unit is a lightweight, low-maintenance truck with four-wheeldrive that can be used for almost any cementing application. Its rugged, compact design enablesoperation even in hard-to-reach locations. The simplicity of design and extensive test programprovide a high level of reliability over rough terrain and in bad weather and allow quick rig-up,rig-down and cleanup. This unit enables as many as six jobs to be performed in one day.

The compact CemSTREAK unit can service wells in difficult-to-reach locations.Designed for fast rig-up and rig-down, the unit can perform multiple jobs in one day.

Equipment



78 Cementing Services and Products

The CemSTREAK unit is equipped with one triplex pump and two 1.1-m3 [6.9-bbl] displace-ment tanks, one of which doubles as the mix tank. The hydraulically driven triplex pump allowscontrol of flow rates and pressures and delivers 127 kW [170 hhp] of power. Two centrifugalpumps enable high-energy mixing, pressurizing the triplex pump as well as bringing water ontothe unit.

The unit carries 38 m [125 ft] of treating hose, rated to 20.7-MPa [3,000-psi] working pressure,to serve as the high-pressure conduit to the well. The hose is stored on an automated reel for fast

deployment and retrieval. A nonradioactive mass-flow meter provides accurate measurements of slurry density, flow rate

and fluid volume even during U-tubing of fluids in the well.Cleaning of the unit starts with the displacement tanks, which minimizes wastewater and

hence environmental impact.

Applications■ Cementing services

■ Low- and intermediate-range pumping services

■ Remedial cementing operations requiring very low pump rates

■ Low-range pressure testing

Benefits■ Ability to reach difficult locations

■ Savings in rig time through rapid rig-up and rig-down

■ Minimal environmental impact

■ Weight compliant with various road ban rules

■ Crew of only two operators for improved logistics, reduced risks and costs

■ Downtime probability reduced or eliminated by reliability of equipment

■ Ability to mix all slurry types

Features■ Four-wheel drive

■ 127-kW [170-hhp] triplex pump

■ Rating of 20.7-MPa [3,000-psi] working pressure

■ 38 m [125 ft] of 50.8-mm [2-in.] hose rated to 20.7-MPa [3,000-psi] working pressure

■ Powered reel for hose storage, deployment and retrieval

■ 1.11-m3 /min [7-bbl/min] pump rate

■ Nonradioactive densitometer

■ SLURRY CHIEF Mark III cement mixer

■ Oilfield or metric gauges

■ Integrated data-acquisition system

■ Two 1.1-m3 [6.9-bbl] displacement tanks

■ CemCAT real-time monitoring

■ Four separate systems for pressure relief

■ Self-sufficient unit, including cement head and extra treating iron



CPF-376 double-pump cement trailerThis cement trailer is a state-of-the-art mixing and pumping unit for land operations. The high-power unit allows mixing and pumping cement at rates to 2.7 m3 [17 bbl/min] and at pressuresto 68.95 MPa [10,000 psi]. Pumps are available with rating to 137.9 MPa [20,000 psi]. The unit isfully redundant, allowing operations to continue in the event of failure of one of its components.

A SLURRY CHIEF mixer with automated density control is used in conjunction witha 0.95-m3 [6-bbl] mixing tub and a 2.2-m3 [14-bbl] averaging tank. This arrangement producessuperior density control and separates the critical mixing stage from downhole pumping.It also provides the ability to mix 3.2 m3 [20 bbl] of cement in batch mode for squeeze and plugoperations.The CemCAT system is used to monitor and record treatment parameters and toprovide a job report.


■ High-power pumping services

■ Remedial cementing operations

Benefits■ Full redundancy ensures ability to complete job

■ Downtime reduced or eliminated by reliability of equipment


The CPF-376 double-pump cement truck delivers high reliability in high-pressure pumping operations.

Equipment 79




Features■ 194-kW [260-hhp] power per triplex pump, for a total of 388 kW [520 hhp]

■ 2.7-m3 /min [17-bbl/min] pump rate

■ Working pressure rating to 137.9 MPa [20,000 psi]

■ Fully redundant for high reliability


■ Automatic density control system

■ Two nonradioactive densitometers


■ Underdrive for pumping at low rates

■ Direct drive centrifugal pumps for reliability


■ CemCAT real-time monitoring

■ Self-sufficient unit, including treating iron

CPT-372 double-pump cement truckThe CPT-372 truck is a high-power cement mixing and pumping unit that allows mixing andpumping at rates to 2.7 m3 [17 bbl/min] and at pressures to 68.95 MPa [10,000 psi]. The unit isfully redundant, allowing operations to continue even if one component fails.

The CPT-372 double-pump cement truck delivers high reliability in high-pressurepumping operations.



Equipment 81

A SLURRY CHIEF mixer is used in conjunction with a 0.95-m3 [6-bbl] mixing tub. This arrange-ment produces superior density control and separates the critical mixing stage from downholepumping. It also provides ability to mix a maximum of 3.2 m3 [20 bbl] of cement in batch modefor squeeze and plug operations.

The CemCAT system is used to monitor and record treatment parameters and to providea job report.


■ High-power pumping services

■ Remedial cementing operations

Benefits■ Full redundancy ensures ability to complete job

■ Downtime reduced or eliminated by reliability of equipment


Features■ Power to 388 kW [520 hhp]

■ Pump rate to 2.7 m3 /min [14 bbl/min]

■ Working pressure rating of 68.95 MPa [10,000 psi]

■ Fully redundant for high reliability





■

CemCAT real-time monitoring■ Self-sufficient unit, including treating iron

Offshore cementing skidsSchlumberger provides a versatile line of CPS* cement pumping skids specially designed to meetall offshore cement mixing and pumping requirements. These skids can produce up to 1,490 kW [2,000 hhp] for high-pressure pumping.

Two triplex pumps equip the unit for simultaneous high-energy mixing and downhole pump-ing or for parallel downhole pumping. Two engines (diesel or electric) power the unit. The designfocuses on reliability, redundancy and noise reduction. The units are typically controlled from a local console but optional remote control packages are available. Optional marine cooling kits

and a helicopter lift unit are available.Cement slurries are mixed using the SLURRY CHIEF recirculating mixer fitted with an SFM

quality control monitor or an SFM-C* process control unit for automatic density control. TheSLURRY CHIEF unit mixes consistent slurries at rates to 1.75 m3 /min [11 bbl/min]. Equalizingtubs provide excellent slurry uniformity (3 m3 [19 bbl]).




Offshore cementing skids are fitted with all sensors necessary for direct connection to theCemCAT data-acquisition and monitoring system. The CemCAT system monitors and recordsthe critical job parameters including rate, pressure and slurry density.

Batch mixers, such as the CBS-961 twin 50-bbl mixer, are available for mixing of cementslurries or other fluids. The CBS-961 unit features two centrifugal pumps for picking up fluidsfrom remote tanks, recirculating for mixing and for delivering fluid to high-pressure pumps.

Standard equipment■ SLURRY CHIEF cement mixer


■ Two triplex pumps

■ Stainless-steel displacement tanks

■ Slurry pump

■ Recirculation pump

■ Two mixing water pumps

■ Full selection of fluid ends

Optional equipment■ SFM package

■ Automatic density control

■ Zone II-certified engine package

■ Remote control package

■ Split skid with bulkhead

■ Optional loose equipment skid

■ Marine cool kit

■ Liquid additive metering system

■ Soundproof enclosure (for CPS-601 and CPS-665 units)

CPS cement pumping skids are available in a number of configurations to fit any requirement.



Equipment 83

Applications■ All cementing jobs

■ High-pressure pumping services

■ Fluid pickup from remote sources

■ Metering of mixing fluids

■ Metering and pumping of displacement fluids

■ Downhole pumping using one or both triplex pumps

LAS liquid additive systemModular systems, such as the CMP-351 unit, deliver metered amounts of liquid additives to thecement slurry as it is mixed. Metering of liquid additives adds versatility to the mixing process,enabling the mixing of various slurry systems from bulk storage of neat cement. Metering can bemanual, or automatic when the CMP-751 LAS metering unit is used. With the CMP-751 unit, elec-tromagnetic flow meters control the additive metered into the displacement tanks.

Applications■ Offshore cementing operations

■ Operations in remote areas

Benefits■ Allows use of neat (unblended) cement for all operations

■ Provides high versatility in slurry designs

■ Simplifies logistics

■ Enables last-minute design without regard to time of transport from base

■ Eliminates waste of unused blended cement

■ Enables decisions on treatment volumes at time of job

Table 6-2. Performance of Offshore Cementing Units

CPS 361 CPS 601 CPS 665 CPS 763AC CPS 763DC CPS 2000

Power (kW [hhp]) 410 [550] 626 [840] 1,044 [1400] 1,194 [1600] 1,194 [1600] 1,490 [2000]

Max. rate at 1.6 [10] 3.1 [19.7] 2.9 [18.3] 2.9 [18.3] 2.9 [18.3] 3.8 [24.0]41.4 MPa [6,000 psi] at 46.9 MPa(m3 /min [bbl/min]) [6,800 psi]

Table 6-1. Dimensions of Offshore Cementing Units

CPS 361 CPS 601 CPS 665 CPS 763AC CPS 763DC CPS 2000

Length (mm [in.]) 6,511 [256] 7,710 [304] 7,863 [310] 8,180 [322] 7,823 [308] 7,164 [282]

Width (mm [in.]) 2,578 [102] 3,011 [119] 2,898 [114] 3,007 [118] 3,150 [124] 3,841 [151]

Height (mm [in.]) 3,043 [120] 3,467 [136] 3,333 [131] 3,339 [132] 3,323 [131] 3,267 [129]

Operating weight (kg [lbm]) 20,658 [45,550] 32,180 [70,960] 33,840 [74,600] 37,360 [82,380] 38,010 [83,810] 46,795 [103,180]




Features■ Meters up to four different additives into mixer

■ Stainless-steel construction for durability

■ Remote control of additive addition

■ Certified for Zone II operations

■ Electromagnetic flow meters

CemCAT cementing computer-aided treatment softwareThe CemCAT system is a quality control (QC) and data-acquisition software for acquiring, record-ing, displaying, and reporting cementing and related pumping treatment data in real time.CemCAT system real-time displays and plots present detailed job information to decision-makers.User friendly and quickly accessible, the CemCAT system provides enough defaults for the systemto be used quickly with a minimum of user input, or it can be completely customized.

By acquiring data from existing hardware on cementing units, the CemCAT system providesefficient data transfer between the Wellsite Reporting System and Schlumberger CemCADEcementing design software. Integration of up-to-the-minute data with design and evaluation software results in precise treatment design and execution. During the job, the CemCAT systemtracks the design and displays actual job parameters compared with planned values.

With the CemCAT system, quality assurance (QA)/QC plots can be generated at the end of each treatment to determine if a job was pumped within the designed density range. Internetconnectivity allows the transmission of data from a remote wellsite to anywhere in the world forreal-time analysis. The CemCAT system also provides the means to easily archive job data forfuture use.

Applications■ Primary and remedial cementing operations

■ Miscellaneous high-pressure pumping services for testing blowout preventers or for leakoff orformation integrity tests

■ Matrix acidizing and coiled tubing services

Benefits■ Superior QC during all treatment phases

■ Precise treatments that follow job design

■ Immediate data for job-critical decisions, thus reducing risk

■ Exceptional flexibility, performance and reliability

Features■ Complete integration with CemCADE design and evaluation software

■ Clear, customizable digital displays and plots of job data

■ Real-time data transmission from wellsite to any location worldwide

■ Detailed postjob plots including QA and QC plots and reports

■ Archive of job data for future use



Equipment 85

SFM-C system instantly displays critical data in convenient, readable formats.

SFM-C process control An important element of successful low-density slurry placement and ideal set-cement proper-ties is QC. A key measure of quality in cement slurries is the solids fraction, which is the percentof dry components in the slurry. In a conventional cementing operation, densitometers measureslurry density, and the solids fraction can be calculated from the density measurements. Variation in the solids fraction of the slurry affects all the cement properties. Too many solids and

the slurry will be too viscous and set early. Too few solids and free fluid will be high and the com-pressive strength will be low and develop late. For certain slurries, such as very low density slur-ries, slurry quality cannot be determined using density measurements.

In ultralightweight slurries, the densities of the dry blend and the mix water can be nearly thesame, so density measurements cannot discriminate between water and solids. The density would be the same, even if the slurry consisted entirely of water. For example, a slurry designedat 1020 kg/m3 [8.5 lbm/gal] with 57% solids content and monitored using only a densitometer with a variation of ± 12 kg/m3 [0.1 lbm/gal] in density will have a solids content ranging from 24%to 84%.

The SFM-C process control system provides a new method for real-time slurry QC that accu-rately determines and controls solid/liquid ratios without making density measurements. Thesystem measures the rate of mix water and slurry flows and calculates the solids fraction fromthose measurements. From this determination, the fluid density is easily computed. The solids

fraction is automatically maintained by process control of the water and cement flow intothe mixer.




The SFM-C system is a complementary technology, designed to provide QC for very low density LiteCRETE slurry systems. Although SFM-C technology was developed specifically for lightweight-cement operations, it is effective for slurries of any density.

This new SFM-C technology allows cementing crews to maintain slurry properties while con-tinuously mixing and pumping large slurry volumes. The system requires a slurry flow meter, suchas the nonradioactive densitometer already available on cementing units, a residence tank sen-sor, a water flow meter and process-controlled valves. These retrofits can be added easily to landor offshore mixing equipment.

User-friendly software helps cementing crews monitor and easily switch between automaticand manual control.

Applications■ All cementing operations

■ Slurries with very low densities (less than 1,320 kg/m3 [11 lbm/gal])

The SFM-C system controls the solids fraction, which in turn controls the density.

100

90

80

70

6050

40

30

20

10

0

0 5 10 15 20 25 30 35 40 45

Time (min)

10

9

8

7

65

4

3

2

1

0

100

90

80

7060

50

40

30

20

10

00 10 20 30 40 50 60 70 80 90 100

Solid frac tion (%)

Volume(%)

Solid frac tion

Slurry density

Slurry rate

Slurry density(lbm/gal)Slurry rate(bbl/min)

88% of volume ± 2% of the solid-frac tion target

99% of volume ± 0.2 lbm/gal

Solidfrac tion

(%)



Equipment 87

The nonradioactive densitometer is a rugged, field-proven instrument with excellent reliability.

Benefit■ Excellent QC

Features■ Continuous-mixing control of all slurries, even at densities equal to or lower than that of water

■

More sensitive method for controlling cement mixing than by density measurement■ Independent of specific gravity of components

■ Automatic control of slurry quality

■ Real-time monitoring

■ Complete compatibility with all data-acquisition systems

■ Easy installation on conventional mixing equipment

Nonradioactive densitometerDensity measurement and control in the oil industry have traditionally been accomplished by using radioactive densitometers, mainly because they are nonintrusive, durable and easy to use.

Unfortunately, the radioactive technique has several major drawbacks; the radioactive sourcepresents safety and environmental concerns, and the required accuracy (12 kg/m3 [0.1 lbm/gal])is difficult to attain.

Because of the deficiencies of radioactive densitometers, Schlumberger uses a nonradioactivedensitometer that employs a proven method; poses no health, safety, or environmental hazard;and provides direct density measurements with an accuracy of better than 12 kg/m3 [0.1 lbm/gal].

The nonradioactive densitometer is extremely reliable, easy to use and requires no on-site cal-ibration. Additionally, it measures flow rate with an accuracy of ±0.5% of reading and can be usedas a flow-measurement instrument for acidizing service. The vibrating tube principle governs thedensity measurement in the nonradioactive densitometer.




Applications■ Cementing operations with slurry density over 1,200 kg/m3 [10 lbm/gal]

■ Land and offshore (including Zone II)

■ Process controlled operations

■ Can be used for acidizing service

Benefits■ Accurate density measurement

■ Reliability, requires no on-site calibration

■ Minimal environmental and safety concerns

Features■ No radioactive source

■ Superior accuracy and field-proven reliability for measuring density and flow rate

■ Accuracy greater than 12.0 kg/m3 [0.1 lbm/gal]

■ Virtually maintenance-free■ Easy configuration; easily drained and cleaned in place

■ Output (density, rate) independent of changes in temperature, pressure, flow profileor viscosity

■ Fast response time

cementing equip

Documents