Sheath Material

Scope

The Technical Specifications regulates the product model, application, technical requirements, test methods, test rules, packaging, labeling, transporting, storing, etc. of 90℃ low-smoke flame-retardant polyolefin cable compound.

The Technical Specifications is applicable to the thermoplastic low-smoke halogen-free flame-retardant polyolefin cable compound with non-halogen polymer as the basic raw material and halogen-free flame retardant, antioxidant, lubricant and other additives added by mixing, smelting, plasticizing and pelletizing.

 

Product Model and Name

Mmodel	Name
AC-101	90℃ Low-Smoke Halogen-Free Flame-Retardant Polyolefin Cable Compound

 

Application

The 90℃ low-smoke halogen-free flame-retardant polyolefin cable compound is mainly used for the jacket layer of communication cables, control cables, signal cables, power cables and other types of cables, the maximum temperature of conductor is 90℃; if it is used for insulating layer, the maximum allowable temperature of conductor is 70℃, and the rated voltage does exceed 0.6kV/1kV.

 

Technical Requirements

1. Appearance

 The product shall be of good plasticity and uniform color, without significant impurities, and shall be cylindrical particulate materials or other shapes of particulate materials with the equal size that the diameter is about 3~4mm and the height is 3mm.

2. Color

The color is determined by the supplier and the demander through negotiation.

3. The performance of the product shall be in accordance with the following table.

Item	unit	Standard values
1. Tensile Strength	MPa	≥ 10.0
2. Elongation at Break	%	≥ 190
3. Thermal Aging100±2℃×240h
Tensile Strength Retention Rate	%	≤ ±30
Rate of elongation	%	≤ ±30
4. Thermal Deformation（90℃×4h）	%	≤30
5. At low temperature embrittlement	℃	-40 through
6. 20℃ Volume Resistivity	Ω•cm	≥5.0×1011
7. Dielectric Strength	MV/m	≥20
8. Oxygen Index	%	≥33
9. Smoke Density  Flameless	—	≤250
With flame	—	≤100
10. Halogen Acid Gas Content	mg/g	≤5
11. pH Value	—	≥4.3
Electrical Conductivity	μS/mm	≤10

 

Test Method

1. Appearance Inspection

Observe with the naked eye under natural light.

2. Preparation of Test Sample

Mix and smelt the product granules on a double-roll open mill at 125±5℃ for 5-10min, then load the test piece and cut. Preheat the loaded cut test piece on a high-temperature hydraulic machine at 170±5℃ for 5min without pressing, then carry out pressing forming for 3min, pressurized cooling for 2-3min, and then remove the mold. After the finished test piece is processed into the test sample according to the test standards, calibrate its size, and then test in this condition.

3. Test of Tensile Strength and Elongation at Break

3. The test of tensile strength and elongation at break shall be carried out in accordance with GB/T 1040.3. The test sample is Type 5 test sample, the thickness is (1.0±0.1) mm, and the tensile speed is (200±50) mm/min.

4. Thermal Aging Test

The effective test pieces of thermal aging shall not be less than five, and the aging treatment shall be carried out in accordance with the provisions of 8.1 in GB/T 2951.2-1997. The test of tensile strength and elongation at break shall be carried out in accordance with 5.3.

5. Thermal Deformation Test

The thermal deformation test shall be carried out according to the provisions of GB/T 8815, the temperature is 90℃, and the time shall be 4 hours.

6. Impact Embrittlement Temperature Test

The impact embrittlement temperature test shall be carried out in accordance with GB/T 5470. The thickness of test sample is 1.6±0.1mm, a total of 30 uncut test samples shall be taken from each group under the conditions in Table 2 to Table 5 of the Standards, and the number of broken test sample shall not exceed 15.

7. Volume Resistivity Test

The volume resistivity tests shall be carried out in accordance with GB/T 1410. The thickness of test sample shall be 1.0±0.1mm, the test temperature 20±2℃, and the test voltage is 1kV.

8. Dielectric Strength Test

The dielectric strength test shall be carried out in accordance with GB/T 1408.1. A symmetrical electrode shall be adopted, the electrode diameter shall be 25mm, and the arc radius of the electrode edge shall be 2.5mm. The thickness of test sample shall be 1.0±0.1mm, the relative dielectric constant of the insulating oil for the test shall be close to 2.3, and there shall be sufficient dielectric strength. The initial test voltage shall be zero, the boosting can be fast from 0KV to 6KV, and the boosting rate shall be no more than 3KV/s from 6KV until breakdown.

9. Oxygen Index Test

The oxygen index test shall be carried out in accordance with GB/T 2406.

10. Smoke Density Test

The smoke density test shall be carried out in accordance with GB/T 8323.

11. Halogen Acid Gas Content Test

The halogen acid gas content test shall be carried out in accordance with GB/T 17650.1.

12. PH value and Conductivity Test

The ph value and conductivity test shall be carried out in accordance with GB/T 17650.2.

 

Inspection Rules

1. Inspection Category

The test is classified into factory test and type test, the factory test is for the following items in batches, i.e. appearance, tensile strength, elongation at break, volume resistivity at 20℃ and oxygen index; and the type test is carried out once every six months during normal production, in case of formula, raw material and process changes that may affect the product performances, the type test shall also be carried out.

2. Batch Classification and Sampling Rules

The product compound takes batch as the unit, those with the same raw material, formula and process are of the same batch, and the number of each batch shall be no more than 10 tons.

A group of test samples shall be randomly selected from three packages of the same batch of products, the appearance shall be firstly tested, the mixing shall be carried out after qualified test, and then the test sample shall be prepared.

3. Quality Determination

In the factory test results, if any item is unqualified, a double sampling test shall be carried out for the unqualified item, if it is qualified after re-test, this batch is determined as qualified, and if it is still unqualified, this batch shall be determined as unqualified.

 

Packing, Labeling, Transporting and Storing

1. Packaging

The 90℃ low-smoke halogen-free flame-retardant polyolefin cable compound shall be of moisture-proof package, the inner bag shall be polythene film bag or aluminum foil/polythene composite film bag, and the outer bag shall be polythene woven fabric/polyethylene/kraft paper composite bag or polythene woven fabric/polythene composite bag, the net weight of each bag shall be 25.0±0.2kg. The other packaging modes agreed by the manufacturer and the purchaser are allowable.

2. Labeling

Each packaging bag shall be marked with manufacturer name, product name, model, batch number, color, date of manufacture, moisture-proof sign and trademark. The packaging bag shall be attached with a qualification certificate. Each batch of products shall be provided with a test report.

3. Transporting

The products shall not be damaged by sunshine, rain, water soaking and abnormal conditions during transport, and shall be kept clean, dry and free from pollution, and the package shall be intact.

4. Storing

The product shall be stored in a clean, cool, dry, well-ventilated warehouse, and the storage period shall not exceed six months from the date of production.