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Guants de protecció de mans contra riscos mecànics (part 1)

1 Terms and Definitions

Els termes i definicions següents s'apliquen a aquest document.

1.1 Protective gloves against mechanical risks

Gloves used to protect against at least one type of mechanical injury risk including abrasion, cutting, tearing, or puncture.

1.2 GIove serIes

A type of glove with the same design or made of the same material from the palm to the wrist, differing only in size, length, left or right hand, and color.

1.3 Braç

The body part between the wrist and the shoulder.

1.4 Number of rubs

The number of revolutions of the outer driven wheel of the Martindale Abrasion Tester.

2 Requisits tècnics

2.1 General protection requirements

The abrasion resistance, resistència a la llàgrima, and puncture resistance of mechanical hazard protection gloves should meet at least the minimum requirements listed in Table 1, level 1. The cut resistance should be at least level 1 as listed in Table 1 or minimum requirement A as listed in Table 2.

Note: Gloves that meet the puncture resistance requirements are not necessarily suitable for protection against sharp objects like syringe needles or other sharp items.

 

 

2.2 Impact protection requirements

Every area claiming impact protection should be tested. Due to the testing method (sample size), it is not possible to test impact protection for fingers.

These gloves should be able to withstand 5J of impact energy. After testing according to method 6.6, the single-conduction force against impact should not exceed 9.0 kN, and the average conduction force should not exceed 7.0 kN.

3 Sampling and Environment

3.1 Mostreig

Samples for wear, cutting, tearing, and puncture testing should be taken from the palm area of different gloves.

3.2 Medi ambient

Samples and other testing consumables (such as sandpaper, EPDM rubber film, canvas, etc.) should be placed in the following environment for at least (24 ± 5) hours:

  • Temperature: (23 ± 2)°C

  • Relative Humidity: (50 ± 5)%

The testing should be conducted in the above-mentioned environment.

Note: If special applications require testing in different environments, the manufacturer is responsible for arranging additional testing and providing the test results.

4 Mètode experimental

4.1 Resistència al desgast

4.1.1 Consumibles

4.1.1.1 Abrasive

The abrasive material should meet the requirements specified in Appendix A.

4.1.1.2 Cinta adhesiva de doble cara

The average adhesive force of the double-sided adhesive tape should be at least 0.2 N/mm, tested according to the method in Appendix B.

Note 1: If the adhesive force is insufficient, the sample will move during the experiment, and in this case, tearing rather than wear may be observed.

Note 2: The suitability of the tape can be verified using the test method defined in Appendix B.

4.1.2 Instrumentació

Feu servir l' Martindale abrasion tester as described in GB/TZ1196.1-2007, with a total mass of (595 ± 7) g for the loading block and specimen holder assembly, ensuring that the specimen withstands a pressure of (9.0 ± 0.2) kPa during the test.

4.1.3 Specimen

Four specimens should be taken from four gloves of the same series. In cases where the palm design is irregular, samples should be taken from the area of the glove with the lowest protective properties (excluding reinforced layers that do not cover the entire palm area). If the specimen is composed of several unbonded layers, each layer should be tested separately. If the specimen is made of bonded layers and the layers can be separated without damaging the material, each layer should be tested individually. Otherwise, the bonded layer should be tested, and the test area should not have seams.

4.1.4 Procediment de prova

4.1.4.1 Specimen Installation

Cut out four specimens with a diameter of (38.0 ± 0.5) mm, attach the specimens to the metal ring in the center without tension using double-sided adhesive tape, then place them under a 10 kg weight for at least 5 minutes. Place the sample holder frame on the assembly platform of the tester base. If the specimen material thickness exceeds the standard ring (e.g., for leather with a thickness greater than 1.2 mm), an additional metal retaining ring should be added, with the opening diameter as shown in Figure 1.

 

To ensure maximum adhesion between the sample and the tape, some materials may require longer pressure bonding times. Surface treatment, such as removing fuzz, can be carried out to improve adhesion between the sample and the tape as long as it does not affect the material’s performance during testing. If a different pressure bonding time (>5 minutes) and/or surface treatment are used, they should be noted in the test report.

Ensure that the sample is not wrinkled when covering the sample cloth frame, screw the sample cloth frame with the sample installed tightly and avoid misalignment of the threads. Maintain constant downward pressure on the sample cloth frame with both hands during screwing.

4.1.4.2 Assembly of Abrasive

Fix the abrasive with double-sided tape, covering the entire surface of the mounting plate. Press the tape on the abrasive to ensure it lays flat on the surface of the test apparatus. If a fixing frame is used, tighten the fixing frame evenly along the diagonals to ensure the abrasive is closely adhered to the surface of the test apparatus without wrinkles or protrusions.

4.1.4.3 Assembly of Sample Cloth Frame

Mount the sample cloth frame on the top plate with a pressure of (9.0 ± 0.2) kPa and start the test apparatus. It is preferable to test four samples simultaneously on the same test apparatus. If the testing times vary, the reasons should be explained in the test report.

After each removal of the sample cloth frame from the test apparatus to check for sample damage, re-tighten the sample cloth frame before continuing the test. If the test needs to be interrupted for a period of time (e.g., overnight or over the weekend), remove the sample cloth frame from the test apparatus, place it with the sample facing up, and cover the sample with clean cards or cloth pieces.

4.1.4.4 Procediment de prova

A new abrasive should be used for each test. After completing 100 friction cycles, inspect the sample for damage. If there is no damage, continue the test until reaching 500 friction cycles (Performance Level 2). Inspect the sample again for damage, and if there is none, continue the test until reaching the number of friction cycles specified for the next performance level as shown in Table 1. Inspect the sample for damage at each performance level’s required number of friction cycles. If damage is found during the performance level check, record it as the previous level of performance. The sample is considered damaged when the following conditions occur:

  • On woven fabrics, when two independent yarns break completely, creating a hole;

  • On knitted fabrics, when one yarn breaks completely, creating a hole;

  • In the adhesive layer, the appearance of the first hole with a diameter of at least 1 mm that penetrates through all layers due to wear;

  • For materials other than those mentioned above, the appearance of the first hole with a diameter of at least 1 mm due to wear.

Each time the sample is inspected to determine the performance level, the test sample and abrasive should be cleaned (e.g., using clean compressed air), and the sample cloth frame should be tightened before returning the sample to the test apparatus. If damage occurs within 2 mm of the edge of the test sample or if the sample is torn, the sample should be discarded, and the entire test process should be repeated. If at least one sample fails in the second test, the lowest value from the samples not discarded in the two tests should be recorded.

If the sample consists of several unglued layers (as per 4.1.3), the final test result is the sum of the test results for each layer. The test report should record the test results for four sets of samples separately, with the performance level being the lowest value among the results from the four sets of tests.

4.1.5 Test Report

The test report should include the following information:

  • Reference to the clause number of this document;

  • Reference information of the sample;

  • Each test result conducted in accordance with 6.1.4;

  • Special treatments to increase the adhesion force between the sample and the tape (such as different pressing times and surface treatments applied to the sample);

  • Reference information of consumables used (sandpaper and tape);

  • Any physical changes observed on the sample;

  • Performance grade determined according to Table 1.

4.2 Cutting Resistance (Circular Blade Test Method)

4.2.1 Instrumentació

The test instrumentation (refer to Figures 2, 3, and 4) consists of the following parts: a) A test workbench with a circular rotating blade that can perform reciprocating horizontal motion. The horizontal movement distance is 50 mm, the blade rotates 360°, with the rotation direction of the blade opposite to its movement direction. This generates a sinusoidal cutting speed of (8 ± 2) m/s. b) Application of a load of (5 ± 0.5) N pressure on the blade. c) Circular blade with a diameter of (45 ± 0.5) mm and a thickness of (0.30 ± 0.03) mm, cutting angles between 30° and 35° (refer to Figure 3). The blade is made of stainless steel with a hardness between 700 HV and 720 HV. d) Support pad made of conductive rubber with a hardness of (80 ± 3) IRHD, such as EPDM rubber sheet, used to place the sample on top. e) Fixture for securing the sample, as shown in Figure 2. f) Device for automatically piercing the sample during testing. g) Rotational counter accurate to 0.1 degrees.

Index Number Description:

1 – Motor and electronic sensors; 2 – Flywheel and transmission rod; 3 – Sliding system; 4 – Connecting rod; 5 – Sample device; 6 – Circular blade; 7 – Serrated rack; 8 – Support plate;

9 – Counter; 10 – Test sample; 11 – Insulating material; 12 – Conductive rubber; 13 – Aluminum foil; 14 – Filter paper; 15 – Top cover plate.

a – Change in the reciprocating motion direction of the blade.

Index numbering explanation: 1 – Warp direction or longitudinal direction; 2 – Weft direction or transverse direction.

4.2.2 Proves de mostres

Each sample is (100 ± 10) mm long and (60 ± 6) mm wide, with the sampling direction at a 45° angle to the direction of the fingers. When the sample is composed of unglued multiple layers, all layers of the entire sample should be tested together. In cases of irregular palm design, samples should be taken from the area with the lowest palm protection.

Two test samples should be taken from two different gloves.

4.2.3 Control Samples

Control samples are taken from canvas, with the same dimensions as the test samples. Technical specifications of the canvas are detailed in 4.2.4.

4.2.4 Canvas

Canvas: The canvas should be a woven fabric; cotton yarn produced by open-end spinning process, with the following characteristics:

  • Warp yarn density: (83 ± 1) tex, 2 strands;

  • Weft yarn density: (250 ± 1) tex;

  • Warp yarn twist: S445 twists/m;

  • Weft yarn twist: Z162 twists/m;

  • Warp density (double yarn): 14 strands/cm;

  • Weft density: 9 strands/cm;

  • Warp yarn tensile strength: 1300N;

  • Weft yarn tensile strength: 1100N;

  • Surface mass: 525 g/m2, with an error of ± 5%;

  • Thickness: (1.0 ± 0.1) mm.

4.2.5 Procediment de prova

4.2.5.1 Installing Samples

Place a 0.01 mm thick aluminum foil on a rubber support pad, then cover it with a non-woven material with a surface mass of (65 ± 5) g/m2 and thickness less than 0.1 mm. Position the prepared test sample on the setup to avoid accidental cutting through due to gaps in the fabric structure.

Place the control sample on top without any tension. Secure the sample fixture on the testing platform and slowly bring the blade into contact with the sample.

4.2.5.2 Calibrating Blade Sharpness

Before starting the test, determine the sharpness of the blade using the following method: Note the blade’s rotational speed (Cn) when the control sample is cut through.

The initial sharpness of the blade should be between 0.8 and 1.4. In the remaining 4 consecutive tests, the blade’s sharpness should be between 0.8 and 2.0. If the blade’s sharpness is below 0.8, reduce it by cutting motions on a three-layer control fabric. If the blade’s sharpness exceeds 2.0 in subsequent tests, replace the blade for further testing. Use a new blade for each new test sample.

4.2.5.3 Passos de la prova

Perform the test on the samples using the same method and record the rotational speed (Tn) when the blade cuts through the sample. Stop the test manually when T reaches a maximum of 60 rotations.

Each sample should undergo 5 tests in the following sequence (with the blade’s initial contact point at both ends of the sample): a) Control sample test (Cn) b) Test sample test (Tn) c) Subsequent control sample test (Cn+1)

For cut-resistant materials, if after the first test on the test sample, Cn+1 is more than three times greater than Cn, conduct a straight blade test (6.3) for cut resistance testing, using the straight blade test method (6.3) to evaluate the cut resistance performance of the gloves.

4.2.6 Calculation of Test Results

The test results are arranged as shown in Table 3.

4.2.7 Test Report

The test report should include the following information:

  • Reference to the clause number of this document

  • Reference information of the sample

  • Test results of each sample calculated according to section 4.2.6

  • Any deviations from the test method

  • Reference information of consumables used (e.g., blades, canvas, etc.)

  • Performance level determined according to Table 1

4.2.8 Dispute Resolution of Test Results

If the cut resistance performance of mechanical hazard protective gloves is marked with its cut resistance performance level using the circular blade test method, any disputes regarding test results should be resolved according to the cut resistance (circular blade test method) (4.2), and the results of the circular blade test method should be used as the arbitration basis. For mechanical hazard protective gloves claiming to have cut resistance performance but not marked with the corresponding level of cut resistance test method, in case of disputes over cut resistance test results, they should be handled according to the cut resistance (circular blade test method) (4.2).

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