The hydraulic burst strength tester uses the elastic diaphragm method (hydraulic explosion) to measure the expansion tension and degree of expansion of woven, knitted, woven, non-woven, paper, plate, and other materials under simultaneous stress in longitude, latitude, and all directions.
Through the circular holder, the sample is clamped to the expandable diaphragm. Then, air or liquid pressure is put under the diaphragm to expand it and the sample. The pressure is kept steady until the sample breaks, at which point the strength and size of the break are measured.
What makes the bursting strength different from the bursting strength of fabric?
During wear, the concentrated load keeps pushing and pressing on the fabric, causing it to stretch until it breaks, especially at the elbow, knee, and other parts of the clothing. “Jacking” or “bursting” are terms for this destructive effect. During the taking process, the jacking and pressing of the fabric causes it to stretch along the length and shrink along the width. If only the tensile breaking strength of the fabric is tested, it must be done in the longitudinal, transverse, and oblique directions.
Breaking in only one direction doesn’t show the wear situation correctly. The jacking breaking strength or bursting strength of a fabric is the force that causes it to break when it is stretched and tested with the right tools. A fabric bursting strength tester and a fabric bursting strength tester are experimental tools used to measure bursting strength and bursting strength. So, a good way to figure out how good a piece of fabric is to look at its bursting strength.
The steel ball method is less stable than the other two. The hydraulic method is the most stable. The main reason is that when the steel ball method is used to burst, the part of the circular sample closest to the center is pressed directly against the surface of the steel ball, which causes friction in that area. This means that some of the load is taken on by the frictional resistance when the two parts slide against each other. This means that the surface friction between the two parts affects the bursting strength. When a sample is hydraulically burst, the pressure of the gas or oil is spread evenly over the sample.
Here are the main things that affect the bursting strength and bursting strength of a fabric:
Yarn breaking strength and elongation at break
When the breaking strength and elongation of the yarn in the fabric are both high, the yarn with high bending stiffness doesn’t break easily when bent, which helps the bursting strength and bursting strength of the fabric.
There are a lot of other things that make a thicker fabric better at burst and burst strength:
- Fabric warp and weft density
When the density of the fabric’s warp and weft are different, but everything else is the same, the fabric will tear in the direction of the low density when it bursts. The fabric is not strong enough to burst, and the crack is straight. When the warp and weft densities are the same, the warp and weft yarns share the load most evenly, and the fabric breaks in an L-shape along both the warp and the weft directions at the same time.
- Yarn hook tenacity
When the hook strength of the yarn coil in a knitted fabric is high, so are the bursting strength and fabric bursting strength.
There are two tests that must be done on fabrics: the bursting test and the non-bursting test. Under the weight of a vertical plane, bursting happens when there is jacking or bulging and expansion (bursting). Bursting is mostly a simulation of how elbows and knees affect clothes. The burst is meant to mimic the stress on fabrics like fire hoses and dust filter bags.
Bullet bursting test using steel balls
Attach the sample to the fixed base’s ring sample clamp. Then, the spherical ejector rod pushes the sample up and down at a constant speed to deform the sample until it breaks, and the bursting strength is measured.
When a jacking force is applied, the yarn first breaks in the direction that can bend and stretch the least and is the weakest. It then mostly breaks along the warp or weft direction. Most of the time, the crack is straight. If the crack is in the shape of an “L” or “t,” it means that the deformation capacity of the warp and the weft are similar and both play the most important role, and that the bursting strength is higher than the straight line. As the fabric’s tensile strength in the warp and weft directions goes up, so will its bursting strength.
In knitted fabrics, the coils are linked together so that the fabric can bend without tearing. So, increasing the coil density in the right way can also make the bursting strength better. Most nonwovens are made of broken and loosening fibers. The bursting strength depends on how strong the fiber fixing point is.
You can put the sample on the diaphragm because it can bend. Then, you put liquid pressure on top of the diaphragm to make it and the sample grow. When the sample breaks, you measure how strong it was when it broke and how much it grew when it broke.
Bursting pressure is the most force that can be put on a sample that is clamped to a diaphragm until the sample breaks. Bursting strength is the pressure you get when you take the average bursting pressure and subtract the pressure of the diaphragm.
The height or volume of the sample when it bursts is called its “bursting height” or “bursting volume.” Bursting height is the distance between the sample’s top surface before it expands and its top surface when it bursts.
Burst volume is the amount of fluid pumped under burst pressure that was under pressure. For the selection of the bursting area, 50 cm2 (79.8 mm in diameter) is recommended for most fabrics, especially knitted fabrics. According to the characteristics of fabrics, 100 cm2 (112.8 mm in diameter, low expansion fabric), 10 cm2 (35.7 mm in diameter) and 7.3 cm2 (30.5 mm in diameter) can also be used.
The sample is clamped to the expandable diaphragm, and the gas is pumped under the diaphragm at a constant speed. The sample will burst when the diaphragm is pushed to a certain height. At this point, the pressure value is equal to the sum of the sample rupture value and the diaphragm jacking force value. Then, measure how much force is needed to raise one side of the diaphragm to the same height. The bursting strength value of the test sample is found by taking the difference between the two values.
When the pressure is less than 800 kPa, there is no difference between the data from the pneumatic method tester and the data from the hydraulic method tester for the bursting strength test. This range of pressure meets the general needs of most products. A hydraulic tester is good for special textiles that need a high bursting pressure.
Comparative analysis of the digital bursting tester and the Mulle bursting tester
Both the Mullen bursting strength tester and the Digital automatic fabric bursting tester are used to find out how strong a material is when it bursts. What is different about them?
The digital automatic fabric bursting tester uses hydraulic blasting to measure the bursting strength and height of materials that are woven, knitted, non-woven, paper, or plates. A smart control algorithm with both manual and automatic control modes keeps the bursting time accurate. It is easy to use because it has PC control software, can analyze and print test results, works with all standard test areas, and meets all the requirements of different standards.
With the Mullen bursting strength tester, you can find out how strong textiles, leather, aluminum foil, plastics, non-woven fabrics, and all kinds of paper are when they burst. The unique transmission device provides stable pressure. The sample can be clamped quickly and accurately with the help of the handle.
How to use a bursting strength tester.
- As soon as the test starts, a relaxed state should be put into place for the sample to be dewatered. The sample will be kept in humidified air during the test.
- The test area is 50 cm2.
- Set a constant volume growth rate between 100 cm/min and 500 cm/min. Or conduct a pre-test and adjust the bursting time of the test to 20 5 S;
- Put the sample on the diaphragm to keep it flat and free of tension and to keep it from changing shape in its plane. Use the clamping ring to hold the sample in place so it doesn’t get damaged and doesn’t move around in the test. Set the device that measures expansion to zero, tighten the safety cover according to the instrument’s instructions, and press on the sample until it breaks. After the sample is broken, immediately reset the instrument and write down the pressure, height, or volume of the sample when it bursts. If the sample fails close to the edge of the clamping ring, you should report this and do at least 5 more tests on different parts of the fabric.
- Using the same test area, volume growth rate, or bursting time as the above test, expand the diaphragm without a sample until it reaches the average bursting height or average bursting volume with a sample, and take the bursting pressure as the “diaphragm pressure”.
The source of the bursting strength error
The low reading is caused by meter error (bias or nonlinearity), meter expansion, meter pointer friction, air in the hydraulic system or meter, too little film sag at the zero scale, and too slow liquid filling rate (manual tester).
The high reading could be caused by gauge error (bias or nonlinearity), a loose gauge pointer (bias value), a bent gauge pointer caused by a blocked needle, not enough clamping force (sliding), uneven clamping force (partial sliding), or the film not being hard or flexible enough. In a test with more than one layer, the zero scale film is higher than the fixture plane. The rate at which liquid is filled is too fast (manual tester) and has broken twice. If the gauge gets out of range by accident, it needs to be fixed before it can be used again.
What are the types of bursting strength testers?
As a technical index, the textile industry, the packaging of cardboard boxes, and other industries need to be tested often right now. There are different kinds of testers, and their jobs are used in different ways. What are the different kinds of burst strength testers?
The scope of use for the Mullen bursting strength tester is to measure the bursting strength or seam bursting strength of knitted fabrics, knitted fabrics, and non-woven fabrics, as well as the bursting force needed to break paper and leather. The Mullen bursting strength tester is a machine that measures the resistance (bursting strength) of textiles, knitwear, paper, and other things when they are damaged by different outside forces. Oil pressure makes the rubber film under the test piece grow. Measure how much pressure it takes to break the sample, and use the following formula to figure out the breaking strength:
The pneumatic bursting strength tester can be used to measure the strength and height of fabrics that are woven, knitted, non-woven, paper, or plates when they burst. It can also be used to measure how strong something is and how tall it is when it breaks.
Hydraulic digital automatic fabric bursting instrument: It is used to measure the bursting strength and height of woven, knitted, non-woven, paper, or plate fabrics. It uses the hydraulic blasting method. A smart control algorithm with both manual and automatic control modes decides when the burst will happen. It is easy to use because it has PC control software, can analyze and print test results, works with all standard test areas, and meets all the requirements of different standards.
The burst strength tester is typically hydraulic or pneumatic. The tested sample bursts when hydraulic pressure acts on it above the rubber tympanic membrane. This is used to test the z-large pressure value and burst height of knitted, woven, paper, and paperboard when they burst.
The hydraulic automatic burst tester uses an imported non-contact linear displacement sensor and a high-precision pressure sensor to test the blasting force and height of a sample at the moment it bursts. The fully clear acrylic test cup makes it easy to watch the sample rise and break during the whole process. The high-power electric push rod has a large torque, stable and accurate pressurization, and the Z pressure can reach 6000 kPa. There are many different kinds of test cups.
The fabric bursting strength tester is used to test the bursting strength and height of woven fabrics, knitted fabrics, paper or plate, leather, and other materials. It uses the hydraulic blasting method (elastic diaphragm method) to measure the performance of expansion tension and expansion degree when force is applied simultaneously in longitude, latitude, and all directions.