[Jan 01, 2026] Latest Questions API-936 Guide to Prepare Free Practice Tests
Reliable API-936 Dumps Questions Available as Web-Based Practice Test Engine
NEW QUESTION # 11
Who is responsible to approve refractory dryout procedures that have more than one heat source?
- A. Inspector
- B. Owner
- C. Manufacturer
- D. Contractor
Answer: B
Explanation:
According to API TR 980 - Monolithic Refractories: Installation and Dryout, when multiple heat sources are used during refractory dryout, the final approval must come from the Owner:
"If more than one heat source is used, the contractor shall obtain written approval from the Owner for the dryout procedure."
- API TR 980, Section 6.2.2
While the contractor may propose or execute the dryout, the responsibility for ensuring its validity and safety-especially when multiple heat sources are involved-rests with the Owner.
NEW QUESTION # 12
The best definition for creep is:
- A. an increase in expansion at high temperatures.
- B. cracking caused by thermal shock.
- C. shrinkage at high temperatures.
- D. deformation due to continuous load over time.
Answer: D
Explanation:
Creepin refractories is the slow, time-dependentdeformation of a material under constant stressand high temperature. It is critical in applications like reformers and furnaces where the refractory is under load for extended periods. The amount of deformation is typically measured over 50-100 hours in standardized tests such as ASTM C832.
Creep is not the same as thermal expansion (which is reversible), or cracking (a sudden failure).
Reference:
API TR 981 -Thermal Expansion Under Load and Creep of Refractories, defines creep as deformation due to a sustained load over time under high temperatures
NEW QUESTION # 13
Materials that are easily reduced to a granular or powdery condition after placement are known as:
- A. friable materials.
- B. calcined frits.
- C. mineral additives.
- D. granular grog.
Answer: A
Explanation:
PerAPI Std 936, friable materials are defined as:
"Friable: A term applied to a material that is easily reduced to a powdery or granular state by crushing or rubbing."
-API Std 936, Section 3: Definitions
This is a key property considered in refractory evaluation because friability can indicate material weakness after installation.
Therefore:
A (friable materials)is the correct and technically defined term.
The other terms refer to distinct classes of materials not defined this way.
NEW QUESTION # 14
The surface of a refractory section not exposed to the source of heat
- A. Smooth face
- B. None of the above
- C. Cold face
- D. Hot face
Answer: C
NEW QUESTION # 15
API 936, the standard test method for abrasion resistance of refractory materials at room temperature is
- A. None of the above
- B. C 704 - 01
- C. C 181 - 91
- D. C 113 - 02
Answer: B
NEW QUESTION # 16
For erosion service, density results are determined from which of the following specimens?
- A. Crushing cubes only
- B. Crushing cubes and linear change bars
- C. Abrasion plates and linear change bars
- D. Abrasion plates only
Answer: C
Explanation:
For linings intended for erosive service, API 936 requires testing that includes specimens that experience real service wear simulation:
"For erosive service, bulk density shall be determined using the abrasion resistance test specimens and the linear change specimens."
- API Std 936, Section 6.4.3
Thus, both abrasion plates and linear change bars are used to evaluate density in erosion-sensitive applications.
NEW QUESTION # 17
Which of the following does not apply to cold crushing strength (CCS)?
- A. Density of sample affects testing loading rate
- B. The loading head of the testing machine shall have a spherical bearing block
- C. Testing shall be in accordance with ASTM C1113
- D. CCS shall be determined on samples that have been fired to 1500°F (815°C)
Answer: C
Explanation:
Cold crushing strength testing must conform to ASTM C133, not C1113. ASTM C1113 applies to thermal conductivity measurements using hot-wire techniques, not compressive strength.
"CCS shall be determined in accordance with ASTM C133. The loading surface of the test machine shall be a steel bearing block with a spherical bearing surface."
- API Std 936, Section 6.4.2
Thus:
A is correct (density can affect rate of loading).
B is incorrect, making it the correct answer.
C and D are correct per standard testing procedures.
NEW QUESTION # 18
Testing to verify that the application equipment and personnel are capable of meeting specified quality standards is called:
- A. quality control testing.
- B. as-installed testing.
- C. applicator qualification testing.
- D. material qualification testing.
Answer: C
Explanation:
Applicator qualification testingis a term used in API 936 to describe the testing required to evaluate whether installation equipment and personnel can achieve the required physical properties (e.g., density, strength) in the final refractory. This testing often involves a mock-up or practice panel where variables like rebound, compaction, and finish are assessed.
The objective is to ensure:
Installation consistency across shifts or crews
Operator competence with specific materials
Adequate equipment settings (nozzles, air pressure, etc.)
Applicator qualification must be completed before production installation begins and is separate from material qualification or final as-installed testing.
Reference:
API Std 936, Section 5.2.2 - "Applicator qualifications shall be demonstrated by pre-installation testing using the proposed equipment and methods." API TR 980 - Sections on "Personnel and Equipment Qualification" and "Field Mock-ups"
NEW QUESTION # 19
Which of the following is false per the requirements of API Standard 936?
- A. Abrasion resistance is determined using two 4-1/2 in. (114 mm) × 4-1/2 in. (144 mm) × 1 in. (25 mm) specimens.
- B. Density shall be determined using cubes or erosion plates and linear change bars.
- C. Permanent linear change is determined with one 2 in. (50 mm) × 2 in. (50 mm) × 9 in. (230 mm) specimen.
- D. Cold crush strength is determined using two 4-1/2 in. (144 mm) × 4-1/2 in. (114 mm) × 4-1/2 in. (114 mm) cubes.
Answer: D
Explanation:
According to API Standard 936, the correct specimen dimensions for cold crush strength testing are:
"Test specimens for cold crushing strength shall be2 in. (50 mm) cubesamples prepared in accordance with ASTM C133."
-API Std 936, Section 6.4.2
This directly invalidates option A, which incorrectly states the specimen size as 4-1/2 inches.
For the other options:
Option B - Density determination:
API 936 states that density shall be measured using the same specimens used for linear change and abrasion resistance:
"Bulk density shall be determined using the same specimens prepared for the linear change and abrasion resistance tests."
-API Std 936, Section 6.4.3
"These specimens include cubes, linear change bars, and erosion plates."
-Appendix A, API Std 936
Option C - Abrasion resistance specimen size:
"Two 4-1/2 in. × 4-1/2 in. × 1 in. (114 mm × 114 mm × 25 mm) specimens shall be prepared for abrasion resistance testing."
-API Std 936, Section 6.4.4
Option D - Permanent linear change specimen size:
"Permanent linear change (PLC) is determined with a bar 2 in. × 2 in. × 9 in. (50 mm × 50 mm × 230 mm) cast in steel molds."
-API Std 936, Section 6.4.1
Therefore, Option A is the only false statement.
NEW QUESTION # 20
Surface preparation and welding procedures are the responsibility of the:
- A. Manufacturer.
- B. Owner.
- C. Inspector.
- D. Contractor.
Answer: D
Explanation:
According to API Std 936 - Refractory Installation Quality Control, the roles and responsibilities of each party are clearly defined. Specifically, it states:
"The contractor shall be responsible for... the preparation of the surface prior to lining, and the quality of the workmanship, including the welding of anchors and any required preheat or post-weld heat treatment."
- API Std 936, Section 5.3.1, Contractor Responsibilities
Therefore, surface preparation and welding activities, including anchor welding, fall under the Contractor's scope of work. The inspector's role is to verify compliance, not to execute procedures.
NEW QUESTION # 21
The surface of a refractory section exposed to the source of heat
- A. hot face
- B. None of the above
- C. smooth face
- D. cold face
Answer: A
NEW QUESTION # 22
The test specimen of castable refractory for cold crushing strength shall be
- A. a or b
- B. 2 in. (51mm) cubes
- C. Cylinders, 2 in. (51mm)in dia. by 2 in.(51 mm) height
- D. none of the above
Answer: A
NEW QUESTION # 23
The maximum angle permitted for gunning below the horizontal is:
- A. 45°.
- B. 60°.
- C. 30°.
- D. 15°.
Answer: C
Explanation:
According to API Std 936, when applying refractory via pneumatic gunning, the angle below the horizontal must be controlled to avoid rebound and poor bonding.
"For downward gunning, the maximum angle below the horizontal shall be 30°."
- API Std 936, Section 6.6.2.1
This restriction ensures proper adherence and consolidation of refractory materials.
NEW QUESTION # 24
Metallic anchor made from rod or bar and usually used for dual layer linings that are configured in
- A. Y shape
- B. V shape
- C. U shape
- D. All of the above
Answer: A
NEW QUESTION # 25
The formation of slag takes place by chemical action and fusion at furnace operating temperature in the way of
- A. In the refining of metals by substances such as lime added for the purpose of affecting or aiding the refining
- B. By chemical reaction between refractories and fluxing agents such as coal ash, or between two different types of refractories
- C. In smelting operation, through the combination of a flux, such as limestone, with the gangue or waste portion of the ore
- D. All of the above
Answer: C
NEW QUESTION # 26
Cristobalite is an important constituent of
- A. Magnesia brick
- B. Silica brick
- C. Alumina bricks
- D. Insulating brick
Answer: B
NEW QUESTION # 27
The vessel in which cracking reaction occurs or is completed and product gases are separated from coke and/or catalyst particulate is called
- A. Cyclones of FCCU
- B. None of the above
- C. Reactor of FCCU
- D. Regenerator of FCCU
Answer: C
NEW QUESTION # 28
In ceramics, the property of resistance to melting, softening, or deformation at high temperature is called.
- A. Cold crushing strength
- B. Refractoriness
- C. Pyrometric cone equivalent
- D. None of the above
Answer: B
NEW QUESTION # 29
For linings that use a surface layer of refractory plastic or a ramming mix, when should trimming, jointing, and venting be done?
- A. After the entire installation is complete
- B. Never; these steps are not required when refractory plastics or ramming mixes are used
- C. Before stopping work for the day or shift
- D. After water curing for 24 hours
Answer: C
Explanation:
When using refractory plastics or ramming mixes, it is critical thattrimming, jointing, and venting be performed before stopping work for the day or shift. API 936 and TR 980 specify that proper surface preparation helps relieve vapor pressure during dryout and prevents cracking. If these steps are postponed, the surface may dry unevenly or set improperly, complicating the subsequent installation and reducing bond quality between layers.
Venting paths are particularly important in thick plastic or ramming layers where moisture may be trapped, and jointing ensures layer-to-layer continuity. Trimming also smooths out inconsistencies and aligns the lining to specifications.
Reference:
API TR 980 - Section "Refractory Plastics and Ramming Mixes: Trimming, Jointing, and Venting" requires these actions be doneprior to any interruptionof installation work.
NEW QUESTION # 30
The most commonly used binder for refractory concrete is
- A. silicates
- B. calcium aluminate cement
- C. all of the above
- D. cements
Answer: B
NEW QUESTION # 31
When water is used for refractory installed on a carbon steel surface with a stainless steel anchorage, the chloride content of the potable water shall not exceed:
- A. 100 ppm
- B. 50 ppm
- C. 200 ppm
- D. 250 ppm
Answer: B
Explanation:
According to API Standard 936, water used in the preparation of refractory mixes is subject to quality limitations, especially when stainless steel anchors are embedded in or come into contact with the refractory that is installed on a carbon steel surface. High chloride concentrations in the mixing water may promote corrosion in stainless steel anchoring systems.
API 936 explicitly states:
"When water is used for refractory installed on a carbon steel surface with a stainless steel anchorage, the chloride content of the potable water shall not exceed 50 ppm."
- API Std 936, Section 5.1.2
This clause is intended to protect the integrity of stainless steel anchors from chloride-induced stress corrosion cracking or pitting, which can compromise the mechanical support of the refractory lining.
Therefore, Option A (50 ppm) is the only correct and code-compliant answer.
NEW QUESTION # 32
The standard test method for abrasion resistance of refractory materials at room temperature is
- A. None of the above
- B. C 704 - 01
- C. C 181 - 91
- D. C 133 - 97
Answer: B
NEW QUESTION # 33
A moldable refractory material that can be extruded and has a level of workability that permits it to be pounded into place to form a monolithic structure
- A. Ramming mix
- B. Monolithic refractory
- C. None of the above
- D. Plastic refractory
Answer: D
NEW QUESTION # 34
For the qualification of the applicator/installer, they shall demonstrate their ability to install the refractory:
- A. to meet the specified quality standards utilized for the installation of work.
- B. free of visible voids, laminations on the hot face or working surface only for gunned lining.
- C. free of visible voids, laminations on the hot face or working surface only of the refractory lining.
- D. by using the technique prescribed by the manufacturer no matter which material is used.
Answer: A
Explanation:
API 936 clearly states that applicators/installers must be qualified to demonstrate the ability to install refractory linings in accordance with the specified project quality standards. This includes using the correct methods, achieving proper material density, and avoiding defects like voids and laminations.
Reference:API Std 936, Section 4.2 - Installer Qualifications: "Installers shall demonstrate their ability to install the refractory system to meet the specified quality standards prior to beginning production work."
NEW QUESTION # 35
Which of the following conditions must be met for test results from trial mixes of low cement castables to be accepted for qualification?
- A. The water content must not vary more than ±1.0% from that recommended by the manufacturer.
- B. Bulk density and CCS must exceed average values published in ASTM C401.
- C. Specimens must be fired at 1500°F (815°C) and held for a minimum of 3 hours.
- D. The drying process must be conducted at 220°F (104°C) for at least 48 hours before firing.
Answer: A
Explanation:
Per API Std 936 Section 6.3.2.1, qualification trials for castable refractories require strict control over water content. The variation must be within ±1.0% of the manufacturer's recommended water addition to ensure consistency and reliability in performance.
"Acceptance of the test results from the cast sample trial shall be contingent on the mix water being within ±1.
0 % of that recommended by the manufacturer."
- API Std 936, Section 6.3.2.1
NEW QUESTION # 36
......
API-936 certification can open up numerous career opportunities in the field of refractory personnel, including technical roles like refractory engineer or quality control specialist, or managerial positions like site manager or project manager. Refractory Personnel certification is not only an asset to the individual but can also benefit the organizations they work for, as it ensures that their personnel possesses the necessary skills and knowledge to carry out the work efficiently and safely. Therefore, obtaining the API-936 certification can enhance an individual's career growth and help organizations maintain a competitive advantage in the market.
Correct and Up-to-date API API-936 BrainDumps: https://www.crampdf.com/API-936-exam-prep-dumps.html
Current API-936 dumps Preparation through Our Practice Test: https://drive.google.com/open?id=1VxzXrt02uD1pyuXf4cuV9aU03MOQa7YS