Resume Flashcards
(83 cards)
1
Q
What does CemCAT means?
A
-cementing computer-aided treatmen
2
Q
Would you be able to displace cement slurry at a pumping rate of 8 bpm and treating pressure of 2000 psi? equipment available for 300 HHP
A
-NO (Presión*Gasto)/40.8
3
Q
What does zonal isolation means?
A
Zonal isolation does not mean to seal off certain zone from others. zonal isolation (that is, to prevent communications between the different zones in a well).
4
Q
Examples of Plastic Formation :
A
salt
5
Q
Examples of corrosive formation fluids are
A
waters containing sodium, calcium, magnesium, or dissolved CO2
- H2S
- CO2
6
Q
API casing specification used to describe a pipe
A
- OD
- Weight
- Grade
- Collapse & Burst Pressure
- Thread Types
7
Q
Key parameters you should know about any working string (casing, drill pipe, tubing).
A
- Collapse Pressure
- Burst Pressure
- OD
8
Q
what does a BLOW OUT is?
A
is an uncontrolled blow of reservoir fluids into the wellbore and sometimes catastrophically to the surface.
9
Q
Part of the BOP:
A
Anular preventer (hydrill)
Pipe Ram
Blind Ram
Shear Ram
10
Q
After bumping the top plug on a 9 5/8-in primary cementing job, when you bleed off pressure, returns do not stop. What happened? What would you do?
A
-Floating equipment failed. Pump back until plug bumps, bleed off rapidly and observe returns again. Repeat twice, if returns still do not stop, hold minimal pressure until cement sets.
11
Q
TOP job cementing job operation
A
-Cement Job Done in the annulus in order to BRING THE TOP OF CEMENT TO SURFACE
12
Q
The key points in top job operation?
A
- Bring cement to surface
- Macarroni Tubing Used
- Max depth 250/ 300 ft
- High Pressure Friction
- No – STD connections
13
Q
Reasons of using TOP PLUG in a primary cementing
A
- Positive Indication of end of DISPLACEMENT
- Separates cement from DISPLACING FLUID to avoid contamination
14
Q
Reasons of using BOTTOM plug in a primary cementing
A
- Separates chemical wah/ spacer & mud to avoid contamination
- It wipes the drilling fluid layer from INSIDE of the casing
15
Q
Plugs are used to :
A
- separate various fluids (e.g., cement from displacement fluid)
- wipe the inside walls of the casing to aid in mud removal
- provide a surface indication of slurry placement by increasing pressure on the surface when the plug seals (this is called “bumping”).
16
Q
Purpose of the conductor casing
A
- Avoid/ Reduce WASHOUT under the drilling rig structure and have a way to return the drilling mud back (Flow Nipple)
17
Q
The surface casing purpose is to
A
- Protect surface FRESH WATER FORMATION , close unconsolidated or LOSS CIRCULATION ZONES and allow BOPS installation|
18
Q
The intermediate casing is run t0
A
- Keep the integrity of the borehole, normally long-string. Support liners run below this string
19
Q
The production casing will
A
- Isolate the pay (production) zone & protect production equipment. Normally small volumes of slurry used.
20
Q
Advantages of STAB – IN cementing?
A
- Less Cement CONTAMINATION
- Less Channeling
- Small Displacement Volume
21
Q
Types of casing string
A
- Conductor
- Surface
- Intermediate
- Production
- Liner
22
Q
Thread used in primary cementing pipe
A
- 8 round
- VAM & Buttress
- Hydrill (integral)
23
Q
Why would we use a liner, select 3 reasons.
A
- Economics
- Cover corroded and damage casing
- Reduce Weight of the casing
- Cover Lost circulation zones, shales and plastic zones
24
Q
Why is recommended to stop down the pumping rate during the last Bbl of displacement?
A
- Is important to slow the displacement to avoid excessive pressure
- Few barrels are pumped before the pump rate must be slowed down (to +/- 2 bpm) to be able to notice the rise of pressure that indicates the liner wiper plug has been released
25
Liner is
- any string of casing whose top is located below the surface. Liners are set by drillpipe, which is subsequently removed. The liner is attached to casing by liner hangers.
26
Intermediate liner
- Intermediate, or drilling, liners are used to cover problem zones during drilling.
- This is not a very common type of liner
27
Tie-back
- Run back to the surface because of corrosion or pressure problems in the casing
28
OVERLAP :
part of the liner is the most critical to cement correctly.
29
Cementing the liner lap
- this has to be a good seal between formation and production path
- liner overlap ranges from 100 to 500 ft, it may vary from 50 to 500 ft.
- Not pump too much cement above the top of the liner 50 to 150 ft is normal.
- Small volume of cement 10 bbl or less
- large volumes of washers and/or spacers to avoid contamination
30
Poor cementing of liners
- communication between the top of the liner and the zone just under the previous casing shoe.
31
Floats leaking after liner job
| Top plug does not bump as per calculated displacement
1. Pump ½ shoe track volume
| 2. Shut down and proceed to checking floats
32
Select the correct plugs used in liner cementing job
- DP dart and Liner wiper plug
33
Liner procedure (by number)
• Pressure test lines.
• Pump wash/spacer.
• Mix and pump slurry.
• Stop pumping and Drop "Pump Down" plug (or drill pipe wiper dart).
• Is recommended to pump Spacer behind the dart to prevent cement contamination when drill pipe is released. Pump enough to cover 200 to 500 ft of drill pipe and liner across the hanger depth. Schematic on next slide
• Complete rest of displacement
- Remember to slow the rate down before reaching setting tool to shear the pins holding the wiper plug inside the liner. Pressure spike should be observed.
• Bump plug /check for returns.
• Release tool.
• Pull up to T.O.C. and reverse circulate
34
The casing hardware elements in a liner cementing job
- Wiper Plug
- Dart
- Liner hanger
35
Slurry chief composed
- knife gate
- mixing bowl
- jets to enhance mixing of the slutty
36
Batch mixing mean
- mixing all of the ingredients in a large tank before pumping downhole
37
Which is the effect of LP-HP jets though the Hopper?
- The streams of mix water supplied by the jets create a vacuum at the top of the mixing bowl. This vacuum, called a venturi effect, helps to pull the cement into the mixing bowl from the hopper
38
How can rate be changed?
- Change the position of the bypass (opening or closing).
| - Change the size of the jets.
39
Select the right description of API mixing energy
The API Spec. 10 document provides explicit directions on how to mix the regulation 600 milliliters of test slurry.
40
absolute volume
the total volume of the material NO void space
The volume per unit mass
The reciprocal of a absolute density expressed as volume per unit mass
41
bulk volume:
The total volume of material and void space
| The volume per unit mass of dry material plus the volume of the air between its particles
42
The slurry yield unit of measurement :
ft3 /sk
43
The definition of slurry yield
- is the ratio of the volume of slurry produced to an equivalent sack when cement and additives are mixed with water
44
The definition of slurry density
- is the weight of 1 gal of the liquid slurry. It is measured in lbm/gal.
45
Materials require additional water when added to the slurry
* D20 bentonite 5.3% (BWOC) for each 1%
* D24 gilsonite 1 gal for each 25 lbm
* D30 silica sand 10% (BWOC) for each 35% of
* D31 barite 0.024 gal for each 1 lbm
* D42 KOLITE 1 gal for each 25 lbm
* D66 Silica Flour 12% r for a 35%
46
Which of the following statements are true:
A. NaCl is added to cement systems by weight of water
B. The quantity of flyash required to prepare 1 cuft of dry blend is calculated by the weight of the cement replaced by the relation between the SG of the flyash over the SG of the cement
Weightflyash = Weight of cement replaced x (SGflyash / SGcement)
C. NaCl is added to cement systems by weight of cement - NO
D. The quantity of flyash required to prepare 1 cuft of dry blend is calculated by the weight of the cement replaced by the relation between the SG of the cement over the SG of the flyash -NOO
A. NaCl is added to cement systems by weight of water
B. The quantity of flyash required to prepare 1 cuft of dry blend is calculated by the weight of the cement replaced by the relation between the SG of the flyash over the SG of the cement
Weightflyash = Weight of cement replaced x (SGflyash / SGcement)
47
Which of the following statements are true:
A. The density of a slurry could be changed by using the appropriate additive
B. If water/solids ratio is not correct, may get high viscosity (unpumpable) and excessive free water
C. Changing the water/cement ratio has the most dramatic effect on density
D. All of the above - SI
D. All of the above
48
Additive is added to the mix water %BWOW
- D044 BWOW
49
To increase the density of a slurry by reducing the water content. What else you do to obtain a pumplable slurry?
- Add Dispersant
50
What is the equivalent weight in lbs for the following Poz/ Cement blend 35/65 (35-La Due)?
Class H 94 x 0.65 = 61.1
D35 94 x 0.35 x (2.51 S.G. fly ash / 3.16 S.G. cement) = 26.13
61.1 + 26.13 = 87.23
51
Why would we use two stage cementing (select 3)
1. reducing hydrostatic pressure on the formation
2. cementing widely separated intervals
3. thickening time
4. reducing costs
5. special needs of the client.
52
What is the alternative for a two stage cementing job to isolate a weak formation
LITEFIL Slurry
| Foamed Cement
53
In a two stage job, when should we wait on the first stage cement to set before pumping the second stage cement slurry?
If the first stage of the cement job is performed to protect a weak zone
54
What is two stage cementing?
is the process of completing two or more isolated cement jobs on the same casing
55
Two stage cement job hardware
* stage collar tool
* bypass plug
* first-stage plug
* opening bomb
* closing plug.
56
Stage collar placement
above a weak or lost circulation zone
With a salt, gas, or other problem zone, the depends on the zone: is toward the bottom of the well is placed above the zone. If it is toward the top of the well is placed below the zone.
At the client's request, the stage collar is often placed inside the previous casing
57
Two stage cement job can cost more than a single liteCRETE job?
Lightweight cement slurries using foam cement or LITEFIL* cement are alternatives to two-stage cementing, but both of these cement systems are expensive to implement in the field.
58
Where would you place stage collar – lost circulation
A stage collar tool is placed immediately above a weak or lost circulation zone
59
Reasons to place stage collar inside the previous casing
This position avoids a "jetting" effect on the formation while circulating and/or cementing.
If the stage collar tool fails to open, the openhole section is cemented, and it is safe not to cement up the second stage.
60
You may suggest start working on a completion work or drilling out to a deeper horizon once you immediately finish a cementing job?
- No,You need the cement to resist at least 500 psi
61
What are the main 2 families of raw materials used to manufacture cement?
Calcareous ( Limestone) and Argillaceous ( Clay)
62
What is the mineral added to the clicker during the final grinding phase of the cement manufacturing process?
- Gypsum
63
How much gypsum is added to Portland cement during the manufacturing process?
- 3-5 %
After the clinker is formed and cooled, it is moved to a second grinding mill where it is combined with 1.5% to 5% gypsum
64
Why is gypsum added to the cement?
- To prevent Flash Set
65
What will happen to cement slurry if you add too much gypsum into cement?
- False set
66
The components of the clinker corresponding to the percentage shown
- C3S (55-65)
- C2S ( 15-25)
- C3A (3-8%)
- CaAF ( 8-12%)
67
What is HSR cement?
- Hih Sulphate Resistance
68
Which of the statements below describes what happens when the cement is exposed to sulphates?
Sulphates react with CeA forming Ettringite
69
Concerning the chemical composition of cements, what is the component and concentration of it that makes the cement HSR?
- <3% of C3A
70
Identify the component of the clinker that corresponds to the description:
the mayor component of the clinker
once hydrated, its increasing the risk of set cement attacked by sulphate
contributes to all stages of strength development
has the highest heat of hydration:
the mayor component of the clinker C3S
once hydrated, its increasing the risk of set cement attacked by sulphate C3A
contributes to all stages of strength development C3S
has the highest heat of hydration: C3A
71
The grain Size for the Portland cement is
- 100 micrones
72
You need to protect yourself carefully with PPE against any contact with cement slurry because:
- Is strongly basic and burn the skin
73
You are mixing cement with 38%water BWOC water / cement ratio, which API class is this cement?
- Class H
74
API class G and class H are extensively used in the oilfiels over a wide depth, temperatures, the main difference between these 2 API cement is:
- Class H more retarder (coarser) than Class G
75
The average specific gravity (sgu) of a grain of cement is:
- 3.15 to 3.20 SG
76
Ettringite is a tri calcium sulfo-aluminate hydrate formed by the reaction of Calcium
False
77
1. Portland cement definition:
Portland Cement is made by heating a mixture of limestone and clay or similar materials to a temperature of 1500°C and grinding it with gypsum to form cement Portland Cement is a hydraulic cement that reacts with water to develop compressive strength
78
Temperature zones in the klin:
```
Evaporation 25 – 100 C
Pre-heating 100 - 800
Dehydration 800 –1100
Exhotermic 1100 – 1300
Sintering 1300 – 1500
Cooling 1500 – 125 C
```
79
What is the klin temperature in C?
-1500
80
What are the main hydration products of C3S and C2S?
- CSH gel, portlandite
81
PORTLAND cement will react at different rate depending on gain size. Based on that, which of the following type of API cement will react faster during the hydration process?
- Class C
82
Surface area of cement grains have influence on the following properties:
- Compressive Strength
- Rheology
- Thickening Time
83
What will be the consequences on set cement when its been attacked by MgSO4?
- Sulfate causes cement to lose many of its properties, including compressive strength.
