Usage 

The CanNeed-PNR-E200 Pressure No Return Tester for Ends can measure the PNR value (Plastic Deformation) and the buckle value of the ends. During the whole pressurization process, use the micrometer to track and measure the deformation amount, generate the curve through the software and analyze the correlation between pressure and deformation amount of the ends.

During the heat sterilization process of the canned products, there will be pressure inside of the can, and the can bottom deforms under the pressure. In normal condition, inside of the can will become vacuum after the can was cooling down, and the can bottom will return from the deformation. However, if the pressure inside the can exceeded the maximum pressure that the can bottom can bear, the deformation will be permanent and can not be return. This will cause the disqualification of the canned products, and therefore may cause the dispute between the canneries and the can and end manufacturers regarding the quality of the can and end.

For avoiding the dispute, the manufacturers shall need to test the maximum bearable pressure of the can bottom before supplying the can or ends.

For the cans which are used in the carbonated beverage (like cola and beer), before leaving the factory, the manufacturers will measure the buckle pressure (buckle deformation) of the can bottom, during the measurement, when the pressure reached a certain value, the can bottom will buckled.

However, for the 2-piece cans that used in the canned food, their diameter is larger, and in the measuring process, they will not buckled as the cans used in the carbonated beverage. Therefore, we need to measure the pressure that caused the no return deformation of the can bottom.

PNR Value Testing Process: Firstly set the initial pressure and the pressurization speed, start the pressurization, track down the deformation amount through the micrometer, when pressurized to the first set point, record down the deformation amount “Sp”, depressurize and record down the remain deformation amount “S0”, through the vacuum negative pressure to make the deformation return to 0.00mm, record down the vacuum degree value “V”, release from the vacuum, record down the remain deformation amount “SR”. Keep pressurize to the second set point and repeat the above measurement.

Advantages

Technical Data

Micrometer measure range : 0-10mm
Micrometer accuracy : ±0,01 mm, ±1digit;
Micrometer units : mm
Pressure measure range : 0-10 Bar
Pressure accuracy : ＜±0,3% of full scale
Pressure units : bar
Data output : RS232C
Power supply : 230V/50Hz
Pneumatic source : 0.5 Mpa
Dimensions : 570 x 400 x 500 (W x D x H )
Weight : 50kg