2022 refrigeration and air conditioning equipment operation examination questions and refrigeration and air conditioning equipment operation examination skills

Source of question bank ： Safety production simulation test, a little public official account.

Pass the safety production simulation exam at one point ： The reference answer of the refrigeration and air conditioning equipment operation examination question and the analysis of the refrigeration and air conditioning equipment operation examination question are the summary of the general question bank of the safety production simulation examination and the students who have passed the refrigeration and air conditioning equipment operation certificate , Relatively effective in helping students pass the examination of refrigeration and air conditioning equipment operation skills .

1、【 Single topic selection 】 When the lithium bromide absorption unit is shut down for a long time , To fill the unit with gas is ( ).（  B  ）

A、 air

B、 nitrogen

C、 oxygen

2、【 Single topic selection 】 Ammonia absorption refrigeration system , The condensation temperature in the condenser is compared with the temperature of the cooling medium ( ).（  B  ）

A、 Low evaporation temperature

B、 Low cooling medium temperature

C、 It's about the same

3、【 Single topic selection 】 For the refrigeration equipment without insulation layer and the outer wall of the pipe bottom , The paint shall be painted in different colors according to the specification , For example, the color of the oil collector is ( ).（  B  ）

A、 silver grey

B、 Ochre yellow

C、 bright red

4、【 Single topic selection 】 Ammonia absorption refrigeration system , The evaporation temperature of the evaporator is compared with the temperature of the cooled medium ( ).（  A  ）

A、 Low evaporation temperature

B、 The temperature of the cooled medium is low

C、 It's about the same

5、【 Single topic selection 】 Under normal circumstances , Intermediate repair must be carried out after the compressor has been running for a certain period of time , This time is ( )h.（  B  ）

A、1000

B、2500

C、5000

6、【 Single topic selection 】 Chemical frostbite is generally divided into three degrees , The level of chemical frostbite that damages the whole skin is ( ) degree .（  C  ）

A、 One

B、 Two

C、 3、 ... and

7、【 Single topic selection 】 The installation requirements of temperature controller in ammonia refrigeration system are ( ).（  B  ）

A、 Horizontal installation

B、 Vertical mounting

C、 It depends on the site conditions

8、【 Single topic selection 】 Split hanging indoor fan does not stop after shutdown 、 The fan runs without startup , The reason is that the fan control ( ).（  C  ）

A、 The capacitor is damaged

B、 The resistance is damaged

C、 Thyristor is damaged

9、【 Single topic selection 】 In order to avoid equipment accidents , The level controller needs to be installed . The liquid level controller is mainly used to control ( ) level .（  A  ）

A、 The highest

B、 The minimum

C、 Liquid difference

10、【 Single topic selection 】 Use steam to clean the site of parts. Once it catches fire , In addition to sand, it can also be used () Put out .（  B  ）

A、 Carbon dioxide

B、 bubble

C、 water

11、【 Single topic selection 】 After the sudden power failure of ammonia refrigeration system , In order to stop the liquid supply to the evaporator immediately , It should be shut down immediately ( ).（  C  ）

A、 Pressure valve

B、 Safety valve

C、 Liquid supply valve

12、【 Single topic selection 】 In case of large leakage of ammonia liquid , In addition to doing the necessary protection work , We also need to find ways to dilute the leaked ammonia , Generally, a large number of ( ).（  A  ）

A、 Water spray

B、 Yang Sha

C、 Fluorine spraying

13、【 Single topic selection 】 The cooling water temperature of lithium bromide absorption refrigeration unit is too high , The possible reason is ( ).（  A  ）

A、 Insufficient refrigerant water

B、 Too much refrigerant water

C、 At low load , The opening of steam valve is too small

14、【 Single topic selection 】 Because the increased flow by hot gas bypass does not produce any useful cooling capacity , Therefore, the hot gas bypass is adopted to reduce the load and reduce the power at the same time ( ).（  A  ）

A、 unchanged

B、 falling

C、 rising

15、【 Single topic selection 】 Centrifugal refrigerator is used for general air conditioner 4℃~7℃ When freezing water , Single stage or ( ) Stage centrifuge .（  A  ）

A、 Two

B、 3、 ... and

C、 Four

16、【 Single topic selection 】 Lithium bromide absorption refrigerator , When lithium bromide solution absorbs refrigerant water vapor in the absorber, it will ( ).（  B  ）

A、 Absorb heat

B、 Release heat

C、 Neither endothermic nor exothermic

17、【 Single topic selection 】 Attention should be paid to the manual operation of guide vane switch type of centrifugal refrigeration unit , At the beginning of start-up, in order to skip the surge prone area of the unit , It is necessary to continuously drive the guide vane to ( )% above .（  B  ）

A、20

B、30

C、40

18、【 Single topic selection 】 For piston refrigeration compressors , When the pressure ratio approaches 20 when , The volumetric efficiency will be close to ( ).（  C  ）

A、10

B、20

C、0

19、【 Single topic selection 】 Non azeotropic refrigerants are ( ).（  B  ）

A、R134a

B、R407c

C、R502

20、【 Single topic selection 】 The principle of socialist professional ethics is ( ).（  A  ）

A、 Collectivism

B、 patriotism

C、 Serve the people

21、【 Single topic selection 】 We must strictly assess 、 Personnel with qualification certificates do not include ( ).（  C  ）

A、 Main person in charge of the enterprise

B、 Safety management personnel

C、 Team leader

22、【 Single topic selection 】 For the refrigeration equipment without insulation layer and the outer wall of the pipe bottom , The paint shall be painted in different colors according to the specification , For example, the color of the oil separator is ( ).（  C  ）

A、 silver grey

B、 Light yellow

C、 bright red

23、【 Single topic selection 】 The centrifugal refrigeration compressor increases the gas pressure through ( ).（  B  ）

A、 The cylinder volume is reduced

B、 The change of kinetic energy

C、 The change of potential energy

24、【 Single topic selection 】 Conduct air tightness test of Freon system , The test medium should be ( ).（  A  ）

A、 nitrogen

B、 oxygen

C、 Compressed air

25、【 Single topic selection 】 The reason why the electronic temperature controlled refrigerator does not defrost may be ( ).（  B  ）

A、 The freezer temperature is too low

B、 Defrost heating circuit fault

C、 The temperature of the refrigerating room is too high

26、【 Single topic selection 】 In order to prevent crystallization of steam type double effect refrigerant due to high steam pressure , The steam pressure should be controlled so that the solution outlet temperature of the high-pressure generator does not exceed ( )℃.（  B  ）

A、100

B、160

C、200

27、【 Single topic selection 】 The centrifugal chiller has the highest efficiency ( ) load .（  B  ）

A、 low

B、 full

C、 zero

28、【 Single topic selection 】 In the refrigeration system , The oil separator is installed in ( ).（  B  ）

A、 Between condenser and expansion valve

B、 Between compressor and condenser

C、 Between evaporator and compressor

29、【 Single topic selection 】 Lithium bromide absorption refrigeration unit , Install a temperature controller on the outlet pipe of the concentrated solution of the high-pressure generator to prevent the solution from overheating , Its temperature is usually set at ( ).（  B  ）

A、180℃-185℃

B、160℃-170℃

C、165℃-175℃

30、【 Single topic selection 】 In industrial cryogenic devices , Most centrifugal refrigerators use ( ) compressor .（  C  ）

A、 Single stage

B、 second level

C、 multistage

31、【 Single topic selection 】 The exhaust temperature of the compressor rises , As the exhaust temperature increases , Deterioration of lubrication conditions , Lubricating oil ( ).（  B  ）

A、 Thicken

B、 Thinning

C、 unchanged

32、【 Single topic selection 】 Capacity fraction of lithium bromide absorption unit ( Bleeding range ) It's usually ( ).（  B  ）

A、3% to 4.5%

B、3.5% to 5.5%

C、5% to 6.5%

33、【 Single topic selection 】 In order to prevent wet stroke and liquid hammer of the compressor , The refrigeration system is equipped with a regenerator to realize the heat exchange between liquid supply and gas return , Improve the efficiency of air return ( ).（  C  ）

A、 humidity

B、 Undercooling

C、 Superheat

34、【 Single topic selection 】 Trial operation of ammonia refrigeration system , The cumulative operation time of each compressor shall not be less than ( )h.（  C  ）

A、12

B、24

C、48

35、【 Single topic selection 】 Pressure vessels with fusible plugs , The maximum pressure that the pressure vessel can withstand shall at least meet the requirements of the critical pressure of refrigerant ( ) times .（  B  ）

A、1

B、2.5

C、5

36、【 Single topic selection 】 Freon is ( ).（  B  ）

A、 The general name of all refrigerants

B、 Fluorine in saturated hydrocarbons 、 chlorine 、 Bromine derivatives

C、 The general name of all lubricating oils

37、【 Single topic selection 】 Electric expansion valve can be divided into deceleration type and ( ).（  B  ）

A、 Hyperactive

B、 Direct acting type

C、 Accelerated

38、【 Single topic selection 】 China's work safety policy does not include ( ).（  C  ）

A、 Safety first

B、 Prevention first

C、 Comprehensive management

D、 people oriented

39、【 Single topic selection 】 The production and business operation entities shall operate at the production and business operation sites and relevant equipment where there are major risk factors 、 Facilities shall be provided with obvious ( ) sign .（  A  ）

A、 Safety alert

B、 Production warning

C、 Safe production

40、【 Single topic selection 】 Ammonia pressure gauge is installed in equipment with large pressure fluctuation 、 When on the pipe , Its impulse pipe ( ).（  A  ）

A、 Damping measures must be taken

B、 There is no need to take shock absorption measures

C、 Determine whether damping measures are required according to the site conditions

41、【 Single topic selection 】 The cause of frost on the suction pipe of the compressor is ( ).（  C  ）

A、 Poor oil return of compressor

B、 Oil non condensable gas in the system

C、 Improper adjustment of expansion valve

42、【 Judgment questions 】 The electric system of water chiller mainly includes power system and control system .（  √  ）

43、【 Judgment questions 】 Power Distribution Box 、 In addition to placing electrical tools in the switch box , Do not place other sundries .（  ×  ）

44、【 Judgment questions 】 Manual energy regulation of screw compressor is realized by manual oil distribution valve .（  √  ）

45、【 Judgment questions 】 When leakage is found in the vacuum pumping stage of ammonia refrigeration system , Repair welding shall be carried out in time , And conduct vacuum pumping test again .（  ×  ）

46、【 Judgment questions 】 The manufacture of marine refrigeration equipment must comply with national standards 《 Code for construction of sea going ships 》 And relevant regulations of classification society .（  √  ）

47、【 Judgment questions 】 Specific heat capacity is one of the important indexes to measure the performance of refrigerant .（  √  ）

48、【 Judgment questions 】 If the cooling tower is not used for a long time after test run , It is not necessary to discharge all the water in the circulating pipeline and sump .（  ×  ）

49、【 Judgment questions 】 Water can be used as both refrigerant and refrigerant .（  √  ）

50、【 Judgment questions 】 The production and business operation unit and the employees conclude labor contracts ( Including employment contract ) when , The possible occupational hazards and their consequences in the process of work shall be 、 Truthfully inform employees of occupational hazard protection measures and treatment , And state in the labor contract , No concealment or deception .（  √  ）

51、【 Judgment questions 】 Centrifugal chillers have no high requirements for machining accuracy and manufacturing quality .（  ×  ）

52、【 Judgment questions 】 The evaporator is different according to the cooled medium , It is divided into cooling liquid and refrigerant 、 Cooling air or other gases .（  √  ）

53、【 Judgment questions 】R134a The thermodynamic properties of R12 Very close to , In the use of R12 In the refrigeration unit of , You can use R134a replace R12 Without making any changes to the equipment .（  ×  ）

54、【 Judgment questions 】 The only element that prevents a short circuit in a circuit is a fuse .（  ×  ）

55、【 Judgment questions 】 When checking the fault of the chiller , Generally according to the electrical system 、 Water system 、 Oil system 、 The refrigeration system consists of four parts .（  √  ）

56、【 Judgment questions 】 In the regulation of refrigerating capacity of lithium bromide absorption refrigeration unit , The economic effect is the best by adjusting the amount of solution circulation , This method is often used alone to adjust the refrigerating capacity .（  ×  ）

57、【 Judgment questions 】 The simplest circuit consists of a power supply 、 load 、 Switch and connecting wire .（  √  ）

58、【 Judgment questions 】 The main factor of gas mixture explosion is temperature 、 Pressure and fire , The medium is only a secondary factor .（  ×  ）

59、【 Judgment questions 】R404A and R410A Mainly used for substitution R22 and R502, The compressed liquefied gas is stored in the steel cylinder .（  √  ）

60、【 Judgment questions 】 It is found that the heat exchanger and pressure vessel have local deformation and bulge , For the safe operation of the equipment , Scrap and replace immediately .（  ×  ）

61、【 Judgment questions 】 Centrifugal water chillers have no piston rings and other vulnerable parts , So the work is more reliable .（  √  ）

62、【 Judgment questions 】 Adding hydrobromic acid to lithium bromide absorption unit can reduce the cost of solution PH value .（  √  ）

63、【 Judgment questions 】 Leak detection of ammonia system , The welding slag at the welding position must be removed .（  √  ）

64、【 Judgment questions 】 Construction personnel have the right to refuse illegal command and force risky operation .（  √  ）

65、【 Judgment questions 】 The principle of regulating energy by slide valve is to use the axial movement of sliding screw , To change the effective axial working length of the screw , Make energy in 100%~10% Continuous stepless adjustment between .（  √  ）

66、【 Judgment questions 】 The five main components of evaporative condenser , They are fans 、 Cooling pipe group 、 Water supply sprinkler system 、 Water baffle and box .（  √  ）

67、【 Judgment questions 】 The employees who obstruct the safety investigation of the accident may be dealt with in accordance with the requirements of the law .（  ×  ）

68、【 Judgment questions 】 Generally speaking , Where there is relative motion , Parts that rub against each other will wear to varying degrees .（  √  ）

69、【 Judgment questions 】 Every time the temperature of a unit substance increases or decreases 1 The heat absorbed or released by degrees is called specific heat or specific heat capacity .（  √  ）

70、【 Judgment questions 】 The basic code of ethics of citizens only includes social morality 、 The content of professional ethics .（  ×  ）

71、【 Judgment questions 】 Ammonia filling in the refrigeration system must be carried out after the air tightness test of the refrigeration system and the thermal insulation works of refrigeration equipment and pipelines are completed and passed the inspection .（  √  ）

72、【 Judgment questions 】 The screw refrigeration compressor or refrigeration unit has undergone strict pressure leak detection and vacuum leak detection during manufacturing , But after transportation and on-site hoisting , It may affect the tightness of the machine , Therefore, after the installation of the machine , Pressure retest is also required .（  √  ）

73、【 Judgment questions 】 All the high-pressure condensate passing through the throttling mechanism is depressurized into the low-pressure condensate required by the evaporator .（  ×  ）

74、【 Judgment questions 】 Piston type multi head chiller , The working medium currently used is generally R22.（  √  ）

75、【 Judgment questions 】 The set temperature difference of the temperature controller is too small, which will lead to frequent operation and shutdown of the compressor .（  √  ）

76、【 Judgment questions 】 When the lithium bromide absorption unit is pumping during operation , After starting the vacuum pump, quickly open the air extraction valve .（  ×  ）

77、【 Judgment questions 】 The actual working process of piston compressor includes suction 、 Compress 、 There are three processes of exhaust .（  ×  ）

78、【 Judgment questions 】 The pressure test and leak detection of ammonia refrigeration system cannot be carried out at the same time .（  ×  ）

79、【 Judgment questions 】 After liquid ammonia splashes on human skin, it must be washed with clean water quickly .（  √  ）

80、【 Judgment questions 】 In order to prolong the service life of centrifugal refrigeration compressor , The user must keep the system sealed .（  √  ）

81、【 Judgment questions 】 Piston chillers can be divided into single head and multi head , Multi head compressors mostly adopt open structure .（  √  ）

82、【 Judgment questions 】 The compressor of AC variable frequency air conditioner generally adopts three-phase induction asynchronous AC motor .（  √  ）

83、【 Judgment questions 】 Safety classification of refrigerants in China , Toxicity classification is divided into A、B、C Three categories , The risk degree of refrigerant combustion is divided into 1、2、3 Three grades .（  √  ）

84、【 Judgment questions 】 Rotary vane mechanical vacuum pump shall be installed horizontally ( place ) Drying 、 ventilation 、 A clean place , Prevent sundries from entering the pump cavity .（  √  ）

85、【 Judgment questions 】 Laws are more effective than rules and regulations .（  √  ）

86、【 Judgment questions 】 Professional ethics is the professional code of conduct that practitioners follow in line with professional characteristics , Cultivate good professional quality through learning and practice , It covers employees and service objects 、 Occupation and staff 、 The relationship between occupation and occupation .（  √  ）

87、【 Judgment questions 】 The most easily crystallized part of the lithium bromide absorption unit is the concentrated solution outlet of the solution heat exchanger .（  ×  ）

88、【 Judgment questions 】 Water lithium bromide absorption refrigeration system , Lithium bromide concentrated solution absorbent .（  √  ）

89、【 Judgment questions 】 Special operation practitioners can go to any training institution with safety training qualification certificate for special operation training .（  ×  ）

90、【 Judgment questions 】 Use refrigerant instead of lubricating oil .（  ×  ）

91、【 Judgment questions 】 The magnetic circuit in the clamp ammeter is composed of a clamp iron core .（  √  ）

92、【 Judgment questions 】 Before installation of ammonia refrigeration system , No single air tightness test is required for auxiliary equipment .（  ×  ）

93、【 Judgment questions 】 Where there is a problem of working without training 、 Enterprises without certificates , Give a financial penalty with a specified upper limit .（  ×  ）

94、【 Judgment questions 】 When installing ammonia refrigeration system , Rubber band must be embedded in the wire perforation of fan and other electromechanical equipment , And do a good job in moisture-proof sealing treatment .（  √  ）

95、【 Judgment questions 】 During the ammonia charging test of ammonia refrigeration system, the vacuum degree of the system shall be used for subsection .（  √  ）

96、【 Judgment questions 】 A worker who has worked continuously for more than one year , Enjoy paid annual leave .（  √  ）

97、【 Judgment questions 】 The surface tension of lithium bromide aqueous solution decreases with the increase of temperature , When the temperature is constant , It decreases with the increase of concentration .（  ×  ）

98、【 Judgment questions 】 The ladder is not allowed to be extended , But the cushion can be used .（  ×  ）

99、【 Judgment questions 】 If the refrigerator of freon refrigerant stops for a short time , The oil heater shall be in automatic heating state .（  √  ）

100、【 Judgment questions 】 Support Yin 、 Male rotor , And ensure that the bearing of rotor rotating at high speed is auxiliary bearing .（  ×  ）

Support the test questions of the operation test of precision refrigeration and air conditioning equipment in all regions of the country , Support safety certificate , Special operation certificate , Exercises on the question bank of vocational skill appraisal and other types of work .