Rubber Testing Equipment has been proved extremely helpful for conducting cylindrical rubber test and determining resistance of vulcanized rubber. A wide range of rubber testing equipment is used in the rubber industries for different testing purposes. We manufacture rubber testing equipments in a wide variety, which include different types. These are designed using modern techniques and a superior quality metal is used for testing the rubber in different ways and available for the industry leading price.
Microcellular sheets used in the manufacture of hawai chappals and shoe soles shall be resistant to slitting if they get split across their thickness. The ability of microcellular rubber sheets and soles to resist propagation of splits is determined by splitting a rectangular test specimen taken from the sheet or sole under test across its thickness and pulling the two split ends away from each other. The maximum load exerted before failure gives the measure of the resistance of the sheet or sole under test to splitting.
Compression Set Apparatus are intended to measure the ability of rubber compounds to retain elastic properties after prolonged action of a known compressive stress under static loading. A set of three test specimens in shape of circular test buttons are placed between rigid metallic plates and pressed under a force of 140 kg. They are allowed to remain under this load for a period of 24 hours, after which the percentage reduction in their thickness is determined and compared against specified values to evaluate their ability to resist compression set.
Flexing endurance of rubber products is determined by simulating in laboratory the action of flexing repeatedly under standard conditions of speed, mode, and degree of flexing.
One of the accepted procedures for determination of flexing resistance makes use of a De Mattia Flex Test. This test provides useful information about the resistance of compounds of vulcanized rubber to flex cracking when subjected to flexing. Cracks develop in that part of the surface where stresses are set up during flexing, or if that part of the surface initially contains a crack, cause this crack to extend in a direction perpendicular to the stress.
One of the methods used for the determination of impact resilience of solid rubbers is based on the measurement of the height of rebound of a standard plunger after it is dropped from a fixed height onto the surface of the rubber specimen under test. This test is conducted on a Vertical Rebound Resilience Tester.
The Globe Impact Resilience Tester(vertical rebound type)consists of a plunger which can be dropped from a fixed height onto the top face of the test specimen, a vertical plunger guide over which the plunger moves during its fall and subsequent rebound, an arrangement to hold the plunger at the specified height and to release it from there, and a scale marked in 100 equally spaced divisions to give directly the rebound height as a percentage of the dropping height.
The Globe Ross Flex Tester consists of an arrangement to hold one end of the test specimens in an oscillating grip such that they can be bent through an angle of 90° at the specified frequency, and adjustable guide rollers to keep the free end of the test specimens pressed down during the bending operations.
The specimen grip has provision for holding six pairs of test specimens at a time. The grip is pivoted on two ball bearings to give a smooth low-friction movement. Movement of the grip causes test specimens to bend over a silver steel ground rod with its axis coinciding with the axis of movement of the grip. The movement is provided by a motor and V-belts through an eccentric and link mechanism. An electronic digital counter with backup memory is provided to record the total numbers of bending cycles.
IS 3400 (Part 16) 1974 : Methods of Test for Vulcanized Rubbers
Part 16 : Measurement of Cut Growth of Rubber by
the use of Ross Flexing Machine
ASTM D 1052 - 1985 : Standards Method of Testing for Measurement of Cut Growth of Rubber by Ross Flexing machine.
Accurate determination of thickness of leather is important in itself for its end use, as well as for evaluating other physical properties of leather under test.
The Globe Bench Thickness Gauge for leather is used for measuring thickness of leather samples with the help of a pressure foot exerting a specified pressure on it. It is also suitable for measuring thickness of leather test specimens whose dimensions are used for determining the results of physical tests or chemical analysis.
The thickness gauge consists of a dial micrometer mounted over a metallic base. The micrometer has a flat circular pressure foot or indentor. A specified force is applied on the leather sample by the pressure foot by means of dead weights placed vertically above it.
The sample whose thickness is to be measured is kept on a flat anvil having its upper face projecting 3 mm from the surface of a flat circular platform. The axes of the pressure foot, the platform, and the projecting anvil coincide with each other.
Tension set is defined as the proportion of applied strain remaining after a rubber piece has been stretched and allowed to recover in specified manner. It is an important property for rubber components that are subjected to tensile stresses either continuously or intermittently.
Tension set is determined by stretching a test specimen of standard dimension by a specified percentage in a suitable apparatus for a specified time and temperature and then allowing it to recover. It is indicated as permanent set retained by the test specimen expressed as a percentage of initial strain given to it.
IS 3400 (Part 13) - 1983 : Methods of Test for Vulcanized Rubbers
Part 13 : Tension Set
IRS T 37 – 1982 : Specification for Grooved Rubber Sole Plates for Placing Beneath Rails
Tensile strength and elongation are the two prime characteristics of most of the raw materials, whether they are metals; or non metals such as rubber, leather, textiles, plastic, paper; or finished products such as rods, wires, ropes, yarns, belts etceteras. These two properties often play a major role in determining the suitability of any raw material for any specified application. It is, therefore, of utmost importance to determine these characteristics accurately, conveniently, and quickly.
The Globe TensileTestingMachines provide a relatively inexpensive way for determining the tensile strength and elongation of a variety of raw materials such as rubber, leather, fabric, plastics, belts, wires, etc eteras. They are based on constant rate of traverse principle, in which one end of the test specimen is held in a stationery grip while the other end is moved at a known fixed speed with the help of a motor, gear box, and screw arrangement.
In electronic type tensile testers, the load exerted on the stationary grip is measured by a load cell and is displayed on a digital indicator. The indicator has a peak force retention memory which can be recalled to display the maximum load exerted on the test specimen before its failure. An overload protection relay is provided to automatically stop the motor if the load exerted goes above the maximum capacity of the load cell.
Permeability of rubber sheets to gases is defined as the rate of volume flow of gas under steady state conditions between opposite faces of a unit cube of solid rubber, when subjected to unit pressure difference under a controlled temperature. The measurement of this characteristic is of important in the evaluation of compounds for products such as inner tubes, tubeless tyre liners, hoses, balloons or other gas containers, seals and diaphragms etc.
The Globe Gas Permeability Tester for rubber consists of a test cell with arrangement for maintaining a constant elevated temperature and a horizontal glass capillary system for measuring the volume of gas permeated.
The test cell consists of metal blocks having independent arrangements for heating with the help of cartridge type heaters. The temperature of each ck is indicated and controlled individually with the help of individual digital temperature indicators cum coblontrollers. Both the blocks are properly insulated to avoid heat losses.
Amongst the various means for the determination of rubber hardness the most important ones are the Durometer and the IRHD Hardness Tester. While the first uses the principle of indentation of a truncated cone in rubber under varying loads acting through a spring, the second method uses a fixed dead load acting on a hemispherical indenting tip. Whereas the first method suffers from the disadvantage of permanent set getting developed in the spring and thus affecting its accuracy, the second method, being based on dead load principle, is free from this problem.
The Globe IRHD Hardness Tester is table model equipment suitable for reference testing of hardness of rubber or similar polymers in the laboratory. It consists of a plunger rod carrying a hardened hemispherical tip of the specified diameter at its lower end. The rod is located within a cylindrical guide and is constrained to move inside it. The base of the guide acts as the pressure foot surrounding the point of indentation. Under normal condition the pressure foot extends below the indenting tip, thus preventing it from getting damaged. An indenting load is positioned over the plunger rod without directly acting on it.
The GLOBESpecificGravityBalance provides a simple and quick mean to read directly the specific gravity of rubber and other elastomers, thus reducing labour and eliminating calculations. The time taken to find out the specific gravity of a sample is only about half a minute.
The balance consists of an anodised scale with specific gravity (SG) printed on it standing vertically on a heavy base plate. A balancing arm is provided at the centre point of the scale. The arm is supported on two jewel bearings to minimise friction.
Two stainless steel pins are suspended from one end of the arm. One of the pins is attached through a short length of yarn and the other through a long length of yarn. The second pin is kept immersed in water inside a tall transparent jar kept on the base.
A pointer is attached at the other end of the balancing arm that indicates the specific gravity of sample under test. A sliding weight is also provided for initial balancing of the samples of different weights. A levelling screw is provided for initial levelling of the base plate.
A sample of any shape can be used for determination of specific gravity. Its weight shall, however, lie between 5 and 15 g. The sample used shall not be soluble in water or be affected by it in any way. If the sample has a cellular structure, the cells shall be of closed type so that the absorption of water is kept at minimum.
From0.9to2.0:graduated in divisions of 0.01
From2.0to2.5:graduated in divisions of 0.02
From2.5to3.0:graduated in divisions of 0.05
Hardness is one of themost important properties which determine the suitability of any rubber component for its intended end use. Incorrect hardness may defeat the basic purpose for which the component is designed. Thus accurate and reliable determination of hardness is of extreme importance in rubber field.
The Shore A Hardness Tester, also called as Durometer, is the most commonly used instrument for measurement of hardness of any rubber component. It is based on the measurement of depth of indentation of an indentor of specified shape being forced into the material under a specified pressure. This test method is an empirical method intended primarily for control purposes. No simple relationship exists between hardness determined by this test method and any fundamental property of the material being tested.
The durometer consists essentially of the following components:
Compression Set tests are intended to measure the ability of rubber compounds to retain their elastic properties after prolonged action of a known compressive stress under static loading.
The Globe CompressionSetApparatusfor determination of compression set characteristics of rubber under constant stress consists of a calibrated loading spring, a set of carbon steel ground and chromium plated plates, and a screw arrangement to compress the spring.
The test specimens are kept between parallel plates and the load applied by compressing the spring. Load acting on the test specimens can be read from a graph, which gives the value of load against spring deflection. A pointer on a scale fixed to the tester indicates the spring deflection.
Maximum number of test specimens
which can be tested simultaneously : Three
Maximum load which can be applied : 800 kg
ASTM D 395 – 1978 : Standard test method for rubber property-compression set
BS: 903 (Part A6) : Determination of compression set under constant load