GAOTek Melting Index Tester with Intelligent Temperature Control

Additional Information

1. Theory and Structure

Melting Index Tester with Intelligent Temperature Control is a kind of Extrusion Plastometer. It can make the sample melt through high temperature oven in specified temperature conditions. The melt sample can be extruded from a die under specified load from the weights. The Melt (Mass) Flow Rate is usually used to express the physical properties such as fluidity and viscosity of macromolecule materials under melt condition in factory plastic manufacture and research of science and research institutes. Melt flow rate refers to the extrudate, the average quality of the sample paragraphs is translated into 10 minutes of extrusion volume.

Melt (mass) flow rate expressed by MFR, unit: g /10 minutes (g /min)

 Formula: MFR (θ, mnom) = tref × m / t = 600 × m / t (g/10min)

• Where: θ – test temperature
• mnom – Nominal Load Kg
• m – the average quality of cut g
• tref – reference time (10min): 600
• t – cut off time interval unit: seconds.

Example:

A set of plastic samples, a cut every 30 seconds, the quality of the results section: 0.0007 lbs. (0.081 g), 0.00018 lbs. (0.086 g), 0.0007 lbs.  (0.081 g), 0.000118 lbs. (0.089 g), 0.0007 lbs. (0.082 g).

Cut the average quality m = 0.0007 lbs. + 0.00018 lbs. + 0.0007 lbs.  + 0.000118 lbs + 0.0007 lbs. ÷ 5 = 0.000184 lbs.

(0.081 g + 0.086 g + 0.081 g + 0.089 g + 0.082 g) ÷ 5 = 0.0838 g ≈ 0.084 (g)

Into the formula: MFR = 1.322 lbs.  (600 g) × 0.000185 lbs.  (0.084 g)/30 min = 0.0037 lbs. g /10 min

(1.680 (g /10 min))

By Industry: For factories and enterprises and research institutes in the production and research.

Meet the criteria: The machine design and manufacture in accordance with the requirements of GB/T3682-2000

2. Keyboard Operation: The operation panel consists of 10 figure buttons from 0 to 9, “.” button and “-” button for inputting figures.

1. Figure buttons, “.” button and “-” button.

The operation panel consists of 10 figure buttons from 0 to 9, “.” button and “-” button for inserting figures.

2. The operation of the function buttons:

2.1 “Menu”, “Ent” and “Esc” buttons:

2.2 The following is the instruction of the LCD screen display:

The LCD screen display includes 8 page layouts, they are initial page, menu page, Parameters Set page, Test Display page, Calibration page, Temp Calibration page, Time Set page PID Set page as shown in the following figures below.

2.3 LCD screen will display after you turn on the power or press “Reset” button.

2.4 LCD screen will display after you press “Menu” key.

• Press key 1~3 select relevant interface.
• Press key 1, you will enter into Parameters Set
• Press key 2, you will enter into Test Display
• Press key 3, you will enter into Calibration.

2.5 Parameters Set

LCD screen will display after you enter into Parameters Set. The options in Parameters Set are as following:

1. θ—-test temperature
2. t —- cut-off time-interval
3. d —- sampling times
4. m —- the test load mass
5. f —- cut-off mode, that is, auto or manual

• Press key 1, it will be displayed in reverse video indicating you to select test temperature.
• Press key 2, it will be displayed in reverse video indicating you to select cut-off time-interval.
• Press key 3, it will be displayed in reverse video indicating you to select sampling times.
• Press key 4, it will be displayed in reverse video indicating you to select test load mass.
• Press key 5, it will be displayed in reverse video indicating you to select cut-off mode.

(Reverse video refers that the displayed color reverses to the normal displayed color.)

Enter a value by figure key after you have selected one of the options and press “Ent” button. The relevant figure key will turn to be normal displaying color. If you have entered a wrong value and didn’t press “Ent” button (At this condition, the figure key remains displaying in reverse video.), Press “Esc” button and enter a needed once again. Press “Esc” button and enter the needed one and press “Ent” button if it is necessary to modify a data.

The temperature value should be Ent within 122 °F – 842 °F (50 ℃ ~ 400 ℃), the cut-off time-interval value should be Ent within 1 s ~999 s, the sampling times value should be Ent within 1~99 and the test load mass value should be Ent according to relevant sample standards.

 The selection of Auto or Manual: If you have selected Auto mode, the rotating cutting tool of the motor will cut the sample automatically when the cut-off time-interval has been reached; if you have chosen Manual mode, the machine will alarm you to rotate cutting tool of the motor manually to cut-off the sample when the cut-off time-interval has been reached.

2.6 The Ent of the average weight of cut-off samples in Test Display

Enter the value by figure buttons and press “Ent” button after one group of tests is finished and the average weight of cut-off samples is calculated. The MFR will be calculated and indicated automatically.

2.7 Testing Machine Main Correction Page

The options in Testing Machine Calibration Page are as following:

1. Temp Calibration
2. Time Set
3. PID Set

• Press key 1, you will enter into Temp Calibration
• Press key 2, you will enter into Time Set
• Press key 3, you will enter into PID Set
  • 1 —-257 °F (125 ℃) Temp. correction value;
  • 2 —- 374 °F (190 ℃) Temp. correction value;
  • 3 —- 446 °F (230 ℃) Temp. correction value;
  • 4 —- 572 °F (300 ℃) Temp. correction value;
  • 5 —- 752 °F (400 ℃) Temp. correction value;
  • 6 —- 842 °F (450 ℃) Temp. correction value.Temp Calibration Page

    LCD screen will display the content of P₆ after you enter into Temp Calibration Page.

    The options in the page are as following:

    Adjustment: 

    After the disassemble of the package, you shall check the main engine, parts and components, accessories and technical document accurately according to packing list and Fig.1. Clean the apparatus and put it on the stable platform after there is no damage and error is found in checking.

    The test temperature correction value of the above-mentioned points equals to actual Temp. minus displayed Temp. plus manufacturer’s Temp. deviation value. For example: the test Temp. constant point is Ent to be 257 °F (125 ℃). Then, the displayed test Temp. is 257 °F (125 ℃) after the temperature is constant, but the actual measured test Temp. is 255 °F (124 ℃). So, the Temp. correction value is 255 °F – 257 °F (124 ℃ – 125 ℃) equals to 33.8 °F (1.0 ℃)..

    The manufacturer’s test Temp. deviation is 32.36 °F (0.2 ℃) and the final Temp. correction value is 30.56 °F ~ 32.36 °F (–1.0 ℃+0.2 ℃) equals to 30.56 °F (-0.8 ℃). If the actual measured test Temp. is 258.44 °F (125.8 ℃), the 257 °F (125 ℃) test Temp. correction value is 258.44 °F ~ 257 °F (125.8 ℃ -125 ℃) equals to 33.4 °F (0.8℃), the manufacturer’s Temp. deviation value is 32.36 °F (0.2 ℃), so the final Temp. correction value is 33.4 °F ~ 32.36 °F (0.8 ℃+0.2 ℃) equals to 33.8 °F (1.0 ℃). The Ent method is as following:

    Press “Ent” button to Esc the manufacturer’s test Temp. correction value after you press figure key 1 to select 257 °F (125 ℃) test Temp. correction value. If the value is negative, enter negative sign by “-” button at first. And then, enter final test Temp. correction value by figure button and decimal button and press “Ent” button. If the value is positive, enter the final test Temp. correction value by figure button and decimal button directly and press “ENT” button. At this time, the relevant figure key turns to be normal displayed colour. If you have entered a wrong value and didn’t press “ENT” button (At this condition, the figure key remains displaying in reverse video.), press “Esc” button and enter the needed one. Press “Esc” button and enter the needed value and press “Ent” button if it is necessary to modify a data.

    You must enter one-digit and one figure after decimal point for every test Temp. correction value, that is, you must press figure button “0” to enter even if the figure after decimal point is zero.

     It is applied to enter every test Temp. correction value. The Ent range of every test Temp. correction value is from 14.18°F ~ 49.82 °F (–9.9 ℃ to +9.9 ℃).

    After you have finished to Ent every test Temp. correction value, you must press “Esc” button or turn off the power of the apparatus and turn on it again so that the new correction value can be efficient.

    LCD screen will display the content of P₇ as following after you enter into Time Set Page.

1. • Enter the value by figure key after you have selected one of the options and press “ENT” button, the relevant figure key turns to be normal displayed colour. If you have entered a wrong value and didn’t press “ENT” button (At this condition, the figure key remains displaying in reverse video.), press “Esc” button and enter a needed one. If it is necessary to modify a data, press “Esc” button and enter the needed value after you have selected relevant option (The relevant figure key displays in reverse video.) and press “ENT” button.You must enter tens digit and one digit for every Time correction value, that is, you must press figure button “0” to enter even if the tens digit is zero.
     • 1—- Year correction value;
     • 2 —- Month correction value;
     • 3 —- Date correction value;
     • 4 —- Hour correction value;
     • 5 —- Minute correction value;
     • 6 —- Second correction value. Enter the value by figure key after you have selected one of the options and press “ENT” button, the relevant figure key turns to be normal displayed colour. If you have entered a wrong value and didn’t press “ENT” button (At this condition, the figure key remains displaying in reverse video.), press “Esc” button and enter a needed one. If it is necessary to modify a data, press “Esc” button and enter the needed value after you have selected relevant option (The relevant figure key displays in reverse video.) and press “ENT” button.You must enter tens digit and one digit for every Time correction value, that is, you must press figure button “0” to enter even if the tens digit is zero.

       LCD screen will display the content of P₈ as following after you enter into PID Set Page.

       • 1 —- select one group among 4 PID groups;
       • 2 —- correction value of P (proportion value);
       • 3 —- correction value of I (integral value);
       • 4 —- correction value of D (differential co-efficient).

       The PID parameters of the machine includes four groups. The 1^st group is used to Ent PID parameter when the temperature content point is within 32 °F ~ 301.82 °F (0 ℃~149.9 ℃); the 2^nd group is used to Ent PID parameter when the temperature content point is within 302 °F ~ 391.8 °F (150 ℃~199.9 ℃); the 3^rd group is used to Ent PID parameter when the temperature content point is within 392 °F ~ 571.8 °F (200 ℃ ~ 299.9 ℃) and the 4^th group is used to Ent PID parameter when the temperature content point is within 572 °F ~ 752 °F (300 ℃ ~ 400 ℃).

       Press key 1 to select a certain group of PID parameter, the key will display in reverse video. Press keys from 1 to 4 in turn, the display turns to be:1 (0~149.9), 2(150~199.9), 3(200~299.9) and 4(300~400). Press ““ENT”” to ensure the modification of a certain group of PID parameter.

       Press keys 2 to 4 to select correction value of P, I and D Ent option separately. The key 2 ,3 and 4 will display in reverse video. Enter the value by figure key after you have selected one of the options and press ““ENT”” button, the relevant figure key turns to be normal displayed colour. If you have entered a wrong value and didn’t press ““ENT”” button (At this condition, the figure key remains displaying in reverse video.), press “Esc” button and enter a needed one.

       Press “Esc” button and enter the needed value after you have selected relevant option (The relevant figure key displays in reverse video.) and press ““ENT”” button if it is necessary to modify a data. The Ent range of P, I and D is 1 s ~100 s, 0 s ~ 3600 s and 0 s ~ 3600 s separately. It is strongly recommended that PID parameters should be modified by professional engineers or you should contact the manufacturer when it is necessary to modify a PID parameter.

        After you have finished to Ent every PID parameters, you must press “Esc” button or turn on the apparatus again after you are turning off it so that the new correction value can be efficient.

   •  (2) The operation of “MANUAL CUT” buttonPress “Start “button in Test Display, the time display in the page will be circularly displayed according to the Ent cut-off time-interval. The cut-off electrical engine will cut the sample once as soon as the time is up to cut-off time-interval and alarms you. The cut-off time-interval stops displaying and the cut-off electrical engine stops cutting when the sampling times has been reached .(3) The operation of “Run “buttonPress “Run” button in Test Display, the apparatus starts to heat and carries out temperature constant process according to the Ent temperature constant point. There is heating indication on the panel during heating process.(4) The operation of “Temp” buttonIt is a dual key. Press the button in Test Display, the display interface will display actual oven temperature, but the heating process doesn’t work. Press the button in other pages, the selected option will be Scaled.

     (5) The operation of “Print” button

     Press “Print” button to print the test report after one group of tests are finished

     (6) The operation of “Rest” button

     Press “Rest” button, the apparatus begins initialization again.

     (7) The operation of “Manual” button

     Press “Manual” button once, the cut-off engine will rotate one circle.

     2. Installation and Operation

   • After the disassemble of the package, you shall check the main engine, parts and components, accessories and technical document accurately according to packing list and Fig.1. Clean the apparatus and put it on the stable platform after there is no damage and error is found in checking.
   • Push the push-and-pull stem which is connected with the die-retaining plate into the oven. You can see that the die-retaining plate covers two thirds of the bottom caliber of the cylinder from the top of it. And then, insert the support stem of bubble level into the cylinder from the top to assure that its bottom surface touches the die-retaining plate.
     • AUTO cut-off: Put the bubble level onto the support stem Take the bubble as reference, adjust the four screws under the base so that the cylinder can be vertical(Note: The procedure is used to avoid excessive friction caused by the piston or bending under heavy loads.). At last, you shall tighten the locknut on the adjusting screws and disassemble the bubble level and the support stem.(1) Die Installation: Install die from the top of the cylinder and press it by charging bar till it touches die-retaining plate.(2) Put the piston stem (compounding part) into the cylinder from the top.(3) Insert power jack and turn on the power switch on the controlling panel, the power light flashes. Ent test constant temperature point, cut-off time-interval, sampling times, nominal test load. Press “START” button after you enter into the test main page. The apparatus begins to heat. Ensure that the cylinder has been at the selected temperature for less than 15 min.

       (4) Wear gloves (in case of scald) and take out piston stem after 15 min. Charge the sample into the cylinder and compress it by charging hopper and packing rod within 1min. Put the piston stem into the cylinder again. The nominal test load can be added onto the piston stem after 4min.

          (5) Extruded samples’ cut-off. The Ent is shown as the above-mentioned AUTO or MANUAL option. Put the tray under the die. Press “AUTO CUT” button when the lower reference mark on the piston stem has reaches the top edge of the cylinder, the cutting tool cut the samples automatically according to the selected sampling times and cut-off time-intervals.

     • MANUAL cut-off Install manual knob on the cut-off engine axis at the back part of the apparatus. Put the tray under the die. Ent the sampling manner to be MANUAL. When the lower reference mark on the piston stem has reached the top edge of the cylinder, press “AUTO CUT” button, the cut-off time-interval has been reached and the apparatus alarms. Rotate manual knob to cut. The manual knob shall be removed when it is under AUTO cut-off mode. (The cut-off shall be carried out between the upper and lower reference marks on the piston stem).
   • (6) Result calculation Select 3~5 no air bubble cut-offs and put them on the balance after cooling and weigh individually (The balance shall be accurate to 0.5mg.), calculate their average mass. Enter average mass in Main Test Page and press “ENT” button. The apparatus will calculate MFR value and displays it in the main interface page. Press “Print” button to print test report.After the above-mentioned procedure, the test is finished.

Attention:            

• The single-phase power jack shall have grounding hole and is stable grounded.
•  Press “Esc” button if LCD screen displays abnormally. Ent the test temperature again and                                       press “START” button
• If the temperature is more than 450℃ during the normal test, the software will be protected,                                   the apparatus stops to heat and alarms.
• If the abnormal phenomenon is such that the apparatus can’t control temperature can’t display                                appear, measures shall be taken to turn off the power and check the apparatus.
• Abrasives or  material likely shall not be used when cleaning the piston stem. Appendix 
  

  MFR (g/10min)	Sample Mass in Cylinder (g)	Extruded Cut-off Time-interval (s)
  0.1~0.5	0.006 lbs – 0.011 lbs (3 g~5 g)	240 s
  >0.5~1	0.0088 lbs – 0.013 lbs (4 g~6 g)	120 s
  >1~3.5	0.0088 lbs – 0.013 lbs (4 g~6 g)	60 s
  >3.5~10	0.013 lbs – 0.017 lbs (6 g~8 g)	30 s
  >10	0.013 lbs – 0.017 lbs (6 g~8 g)	5 s~15 s
  1. It is recommended that a melt flow rate shall not be measured if the value obtained in this test is less than 0.1g/10min or great than 0.22 lbs./ 10 min (100 g/10 min). 2. When the density of the material is greater than 0.0022 lbs. /cm3 (1.0 g/cm3), it may be necessary to increase the mass of the test portion. 3. To achieve adequate repeatability when testing materials having an MFR greater than 0.055 lbs. / 10 min (25 g/10 min), it may be necessary either to control and measure cut-off intervals automatically to less than 0.1s or to use MVR method.

  Material	Test Temp. (θ in °F/ ℃)	Nominal test load (mnom in lbs/kg)
  PS	392 °F (200 ℃)	11.02 lbs (5.00 kg)
  PE	374 °F (190 ℃)	4.76 lbs. (2.16 kg)
  PE	374 °F (190 ℃)	0.71 lbs. (0.325 kg)
  PE	374 °F (190 ℃)	47.6 lbs. (21.60 kg)
  PE	374 °F (190 ℃)	11.02 lbs (5.00 kg)
  PP	446 °F (230 ℃)	4.76 lbs. (2.16 kg)
  ABS	428 °F (220 ℃)	22.04 lbs. (10.00 kg)
  PS-1	392 °F (200 ℃)	11.02 lbs (5.00 kg)
  E/VAC	302 °F (150 ℃)	4.76 lbs. (2.16 kg)
  E/VAC	374 °F (190 ℃)	4.76 lbs. (2.16 kg)
  E/VAC	257 °F (125 ℃)	0.71 lbs. (0.325 kg)
  SAN	428 °F (220 ℃)	22.04 lbs. (10.00 kg)
  ASA, ACS, AEC	428 °F (220 ℃)	22.04 lbs. (10.00 kg)
  PC	572 °F (300 ℃)	2.64 lbs. (1.2 kg)
  PMMA	446 °F (230 ℃)	8.37 lbs. (3.8 kg)
  PB	374 °F (190 ℃)	4.76 lbs. (2.16 kg)
  PB	374 °F (190 ℃)	22.04 lbs. (10.00 kg)
  POM	374 °F (190 ℃)	4.76 lbs. (2.16 kg)
  MABS	428 °F (220 ℃)	22.04 lbs. (10.00 kg)