Test method for rice cookers

Test method for rice cookers  

(1) Test conditions  

Environmental Requirements:  

Unless otherwise requested. The test shall be conducted in the following environments:  

1. Ambient temperature (20±5) ℃;  

2, relative humidity 45%-75%;  

3, atmospheric pressure 86kPa~106kPa  

4, single-phase power supply voltage 220 V× (1±1%)  

5. Power supply frequency (50±1) Hz  

(2) Instruments and meters for testing  

(3) Inspection methods for appearance requirements  

Use tactile and visual methods.  

(4) Parts test  

1, paint parts constant humidity and heat test  

The paint and spray parts shall be cleaned according to the procedures and test methods specified in GB2423.3.  

2, electroplating parts salt spray test  

The plating parts shall be oiled and cleaned according to the procedures and test conditions specified in GB2423.17.  

3. Physical performance test of enamel parts  

(1) Tight performance test  

Place the mouth of the sample downward on the test table smoothly, in a positive position, so that the 100g steel ball falls freely from the top of the sample to the center of the bottom of the sample, and check the degree of bonding between the glaze and the metal after the deporcelain of the sample.  

Note: when the sample height of 300 ㎜ or above, the height of the ball is 200 ㎜; When the sample height of 300 ㎜ below, the height of the ball is 150 ㎜.  

(2) Heat fusion test  

A small piece of AR reagent metal tin foil was placed at the bottom of the sample at the heating position, and gradually heated on the sand bath. When the tin foil melted, it stood at 232℃  

That is, pour clean water at 20℃ into the sample, and then test the porcelain surface at the foil.  

4. Corrosion resistance test of aluminum parts  

The surface of the specimen is wiped with cotton stained with sprinkled fine, and then a small circle of about 0.5cm^2 is formed with molten paraffin wax at the test site of the specimen. The specimen was placed in a 35℃±1℃ constant temperature box for 30 minutes, and then a drop of 10% sodium hydroxide solution was placed on the surface of the paraffin wax, and a stopwatch was used to time it. At 30 seconds, the sodium hydroxide solution was wiped with absorbable cotton, and then the copper sulfate solution was dropped in the original place, and the color was not changed within 5 minutes.  

Note: For the formula of copper sulfate solution, 20ml of hydrochloric acid with a specific gravity of 1.19 was added to 1000ml of distilled water and 20g of crystalline copper sulfate was added.  

5. Performance test of silica gel parts  

(1) Odor test  

Use 250g silica gel parts +1000ml pure water, boil for 2h, and let cool at room temperature.  

(2) high temperature resistance test  

The samples were uniformly loaded with 5kg items and kept at (200±3) ℃ for 4 hours, then cooled to room temperature naturally.  

(3) expansion degree test  

Samples of 3g~6g silica gel were soaked in white lamp oil (kerosene) for 1h, taken out and dried for 4h, then weighed.  

(5) Inner pot  

1, volume measurement  

Weigh the net weight of the inner pot G1, lay the inner pot flat, pour water into it to the maximum volume, weigh the weight of the inner pot and water G2, and calculate the actual situation of the inner pot according to the following formula  

2. Strength test of metal inner pot  

The sample was placed on the wooden platform, and then the steel ball with a net weight of 535g was placed on the top of 380mm above the impact surface. After the free fall through the tube, the deformation depth and visual surface phenomenon were measured after impact.  

3. Wear resistance test of hard oxide film  

Place the sample on the wear-resisting machine, apply 50N pressure, add 0.5% detergent and water, use 3M-7447C cleaning cloth, change the cleaning cloth every 250 times. The total number of tests was calculated by using 10 substrates to terminate the test.  

4, the inner pot anti-stick coating test  

(1) adhesion test  

At the bottom of the inner pot, use a grater to draw 100 square grids of 1mm*1mm with a meson knife. Pour boiling water into the inner pot and soak it for 15 min. Then pour out the hot water in the pot. Cool for 15 min, wipe the coating water and impurities with a paper towel, tape the coating tightly with 3M SCOTCH NO898 tape at the same 45° diagonal position (to ensure good contact with the coating, rub the tape firmly with your fingernail), then quickly pull the tape at a 90° Angle and repeat 5 times.  

(2) Wear resistance test  

Use 5% concentration washing water, 3M(7447C) cleaning towel, load 25N, swing from side to side for 1 stroke, every 250 strokes, replace cleaning towel, every 250 strokes to check whether the coating leakage of the substrate.  

(3) anti-viscosity test  

Gently wipe the surface of the anti-stick coating with a soft cloth stained with vegetable oil, wash with warm water and detergent, rinse with clean water, wipe dry. Then the sample was heated and measured with a surface thermometer. When the surface temperature of the inner coating was 140ºC~170ºC, a fresh egg was put into the pot after breaking the shell, without vegetable oil or other fat oil. When the protein was basically solidified (the inner surface temperature of the sample should not exceed 210ºC), the egg was removed with a non-metallic spatula and the coated surface was wiped with a soft cloth. Do it three times in a row.  

(6) Thermal efficiency  

1. Thermal efficiency test  

2. Classification of thermal efficiency  

(7) Pot bottom temperature test  

Add 50ml water to the inner pot, fix the temperature sensing contact of the temperature monitor at the center of the bottom of the inner pot, apply 80% rated voltage for heating, and read the temperature value within 5s after the temperature limit automatically cuts off the power supply. Repeat the test 3 times, taking the average of the readings as the bottom temperature.  

(8) Insulation temperature test:  

Cook with the maximum amount of rice. At the 4th hour, the 4th hour, the 4th hour, the 4th hour, the 4th hour, the 4th hour, the 4th hour, the 4th hour, the 4th hour, the 4th hour, the 4th hour, the 5th hour, the temperature is measured in the cylinder of the center of the rice with the diameter of 50mm, and the test point is 20mm±5mm away from the bottom of the pot. The average value of the three readings is the insulation temperature.  

(9) Cooked Rice Test (refer to Appendix C)  

(10) Timing deviation test  

The maximum timing time is T max. Set the timer to 1h and T max respectively. Wash the rice according to the maximum cooking quantity of the inner pot, drain water according to the standard water level, and cook the rice under the rated voltage. Measure the time from the start of timing work to the time of entering the heat preservation, and calculate the deviation from the pre-selected timing time.  

(11) Clock deviation test  

Using a timer with an accuracy of 0.1 second, measure the time of the timer corresponding to one month of the rice cooker clock (calculated on a 30-day basis) and note the deviation.  

(12) Air tightness test  

The rated voltage is 1.1 times the voltage, add about 80% cold water to the inner pot, place the inner pot in the front, the back, the left and the right side of the position, boil until the water is dry. In the process, in addition to the design of the exhaust parts, the rest of the parts shall not have obvious leakage phenomenon.  

(13) Working pressure test of pressure rice cooker  

Under the rated voltage condition, add 40% of the rated capacity of water into the pot, install the pressure gauge on the pot cover with the special connector of the pressure gauge, and close the pot cover. Set in the highest pressure function, switch on the power to start heating, until the heat preservation state. Record the highest pressure value during the test.  

(14) Durability test  

Under the condition of 1.1 times the rated voltage, add 15% of the rated volume of water to the inner pot, power work, until the end of the work or converted to heat preservation, and then power off cooling to room temperature for one cycle, repeat the above test, a total of 500 cycles.  

(15) Fastness test of product assembly and packaging  

1. Drop test with packaging  

Test and drop height.  

2. Transport with packaging or simulated transport test  

The factory unpacked rice cooker should be placed on the truck (the rice cooker and the counterweight should be 10% of the rated load of the car). Under the condition of the third grade highway, the car can run for 200km at the speed of 35km per hour, or the factory unpacked rice cooker should be placed on the simulated transport vibration table for simulated transport test. The main vibration frequency of its power spectrum f 1 =2.7Hz±0.5Hz, f 2 =7Hz±0.9Hz, 2.5 hours of continuous simulated transport vibration test, and then remove the package for inspection.  

(16) Safety performance  

Safety performance should meet the requirements of GB4706.19.  

Ii. Inspection rules for rice cookers  

(1) The inspection of automatic rice cooker is divided into factory inspection and type inspection.  

In the factory inspection and type inspection, all the inspection involving GB4706.19 and GB4343.1 shall meet the requirements of this standard in the column of "Category of Nonconformity" (marked with ※) in Table 4 and Table 6. If one item does not meet the requirements of this standard, the batch of products shall be judged as unqualified.  

(2) Factory inspection  

1. Factory inspection refers to the test to be carried out when the product is delivered. Automatic rice cooker must pass the factory inspection before leaving the factory. Test items and requirements for ex-factory inspection.  

2. When the product is delivered, if the ordering party has any doubt about the product quality, it has the right to request to add ex-factory inspection items within the type inspection items. In this case, GB/T2828.1 sampling is adopted.  

3. In case of any dispute between the ordering party and the factory in selecting the type of sampling scheme for ex-factory inspection, the second sampling scheme for normal inspection of GB/T2828.1 shall be adopted according to the provisions of this article, and the discriminant level I and qualified quality level (AQL) shall be: Class C unqualified, AQL=6.5.  

4. The unqualified batch shall be returned to the supplier for 100% reinspection, and the unqualified product shall be removed and submitted again for inspection. For resubmission for inspection, the sampling scheme for enhanced inspection shall be adopted.  

(3) Type test  

1. When one of the following conditions occurs, type test should be carried out.  

a. Trial production appraisal of new products or old products transferred to the factory;  

b. After the formal production, if there are major changes in design, materials, process and structure that may affect the product performance;  

c. Inspect once a year for normal mass production;  

d. When the production is resumed after half a year of suspension;  

e. When there is a big difference between the ex-factory inspection result and the last type inspection;  

f. When the national quality supervision agency puts forward the requirements for type inspection.  

2. The content of type test includes the requirements stipulated in Chapter 5 and 8 of this standard and GB4706.19 and GB4706.4343.1. The test items, requirements and nonconformance categories shall be specified in Table 6.