Exploring the production process of steel wire armor cable armor

Cables that need to withstand large mechanical forces should have an armor layer. The most common types of armored cables are steel tape armored cables and steel wire armored cables. 

Steel wire armored cables are further divided into thick steel wire armored cables (usually used for submarine cables and cables with larger outer diameter power cables) and thin steel wire armored cables (usually used for cables such as exploration cables, mining cables, and control cables).

In the domestic cable market, steel tape armored cables account for a large share; in foreign cable markets, wire armored cables are more commonly used. The most commonly used wire-armored cables are wire-armored power cables and wire-armored control cables. 

When manufacturing steel wire armored cables, relevant national and international standards (or related technical specifications) shall be strictly implemented to ensure that the cable after armor has a stable structure and performance during use. 

Steel wire armored cables mainly implement the following two product standards and two related standards:

GB/T 12706-2008 "Rated voltage 1kV to 35kV extruded insulated power cable and accessories" (or IEC60502) and GB/T 9330-2008 "plastic insulation control cable"; GB/T 2952-2008 "cable outer sheath" And GB/T 3082-2008 "hot-dip galvanizing or hot-dip galvanizing - 5% aluminum-mixed rare earth alloy coated low carbon steel wire for armored cable"

1. Standard requirements and understanding of steel wire armored cables

GB/T12706-2008 "Rated voltage 1kV to 35kV extruded insulated power cable and accessories" (or IEC60502) is the standard for steel wire armored power cables. 

This standard requires steel wire armor (in accordance with GB/T12706.1-2008) :

Material: The steel wire should be galvanized steel wire. The single-core cable armor used in the AC circuit should be made of non-magnetic materials. The non-magnetic metal wire usually has stainless steel wire, aluminum alloy wire, etc. (12.2 of GB/T12706.1-2008).

Wire diameter requirements: nominal diameter of steel wire: 0.8 mm, 1.25 mm, 1.6 mm, 2.0 mm, 2.5 mm, 3.15 mm (12.4 in GB/T12706.1-2008); the minimum diameter of the wire is not less than 95% of the nominal diameter ( 16.7.3) in GB/T12706.1-2008.

Armoring requirements: Steel wire armor should be tight, even if the gap between adjacent steel wires is the smallest (standard GB/T12706.1-2008 12.6).

GB/T9330-2008 "Plastic Insulation Control Cable" is the standard for steel wire armored control cables. 

This standard refers to GB/T2952.1-2008 standard and is an indirect reference to GB/T 3082-2008 standard.

Material: Steel wire should be galvanized steel wire (6.6.2 in GB/T9330.1-2008).

Wire diameter requirements: nominal diameter of steel wire: 0.8 mm, 1.25 mm, 1.6 mm, 2.0 mm, 2.5 mm (6.6.2 in GB/T9330.1-2008); wire diameter tolerance should comply with GB/T 3082-2008 (GB /T9330.1-2008 in 6.6).

Armoring requirements: The steel wire armor consists of a single layer of steel wire left or double steel wire inner layer right and left outer layer wrapped on the inner liner, and the sum of the gaps between the steel wires should not exceed the diameter of one steel wire ( 6.6.1) of GB/T9330.1-2008.

2. The quality requirements for armored steel wire

Control cable armor quality should comply with GB/T 3082-2008 "hot-dip galvanizing or hot-dip galvanizing - 5% aluminum-mixed rare earth alloy coated low carbon steel wire for armored cable".

Low-voltage power cable wire armor quality can refer to GB /T 3082-2008 "Hot-galvanized or hot-dip galvanized-5% aluminum-mixed rare earth alloy coated low carbon steel wire for armored cables", but it is not necessary to evaluate according to this standard.

There are two types of wire coatings for armoring: one is a galvanized layer; the other is a galvanized-5% aluminum-mixed rare earth alloy coating. 

Most of the steel wires used in daily production are galvanized.

The wire coating grade is divided into two groups according to the weight of the coating: Group I and Group II. 

The standard stipulates that armored steel wire should preferably use the following nominal size steel wire: 0.8 mm, 1.25 mm, 1.6 mm, 2.0 mm, 2.5 mm, 3.15 mm, 4.0 mm, 5.0 mm, 6.0 mm. 

From the standard provisions, we can see that the allowable range of the diameter deviation of the armored steel wire is still relatively large, and the wire diameter does not include the non-metallic corrosion-resistant layer on the steel wire. Depending on the manufacturer's process control level, the parties can negotiate to allow the use of steel wire larger than the specified diameter.

For the technical requirements of the joint, the standard emphasizes: "The wire delivery coil should consist of one steel wire, the steel wire can be welded before the last drawing; the finished steel wire with plating should not have any joints."