Semi-conductive Compound Supplier

Our Product Range

We organise our supply around two product families. Power cable shield compounds are the core of our manufacturing programme, engineered for extrusion onto conductors and insulation in cross-linked and thermoplastic cable constructions. Textile tubes serve cable assembly, protection and industrial applications where a flexible, durable sleeve is required.

Where Our Compounds Fit

Semi-conductive shielding compounds sit between the conductor and the insulation, or over the insulation, in a power cable. Their job is to equalise the electric field, suppress partial discharge and protect the insulation from local stress. The material must extrude cleanly, bond or strip as specified, and hold a stable volume resistivity through the cable's service life.

• LV and MV distribution cables (1 kV to 35 kV): conductor shielding and insulation shielding for urban grids, industrial parks, wind and solar generation, and rail transit.
• HV transmission cables: super clean and smooth conductor and insulation shielding compounds for high-voltage cable systems.
• Thermoplastic and Sioplas constructions: strippable and non-strippable shielding compounds for thermoplastic and Sioplas processes.
• Specialty and custom cables: formulations for demanding environments where standard grades do not meet the process or performance target.

Product Range and Application Matching

Critical Specifications We Work To

Shielding compound performance is defined by a small set of measurable properties. We confirm these against the cable design and the extrusion process before a grade is released for a project.

• Volume resistivity: stable semi-conductive behaviour, typically below 100 Ω·cm for conductor shielding, to guide leakage current and avoid field concentration.
• Surface smoothness and cleanliness: low contamination and controlled surface finish to reduce the risk of partial discharge at the shield–insulation interface.
• Bonding or stripping behaviour: bonded grades for a stable interface, easy-strippable grades for cable jointing and termination work.
• Process performance: melt flow and extrusion behaviour matched to the line speed, crosshead and curing method.
• Copper oxidation resistance: grades formulated to limit copper-catalysed degradation in service.
• Environmental compliance: halogen-free formulations compliant with RoHS and related environmental requirements.

Capacity, Consistency and Delivery

Our 13 dedicated production lines and 62,000-ton annual capacity are supported by automated process control, which keeps batch-to-batch output stable for cable manufacturers running continuous extrusion. Monthly production capacity is 5,200 tons, and we hold over 40% of the domestic market for medium- and high-voltage grade shielding compounds.

Standard delivery lead time is one week for available grades. Products are supplied in moisture-protected packaging with a stated shelf life of nine months; storage and handling instructions are provided with each shipment.

Quality Assurance and Compliance

We operate under a certified quality management system and test shielding compounds against international and Chinese industry standards. Our products comply with UL, IEC, GB and other applicable standards, and our formulations were developed to replace imported medium- and high-voltage shielding compounds in domestic cable production.

Our R&D team includes PhDs and senior engineers who participate in national and industry standards work, and we maintain a graduate workstation with Jiangsu University of Science and Technology. We hold 3 authorised invention patents and 40 authorised utility model patents, with further applications in progress.

Customisation and Technical Support

Standard grades cover most LV, MV and HV cable constructions, but cable designs differ in conductor size, insulation thickness, curing method and line speed. We provide customised formulations where a standard grade does not meet the process window or the electrical target, and we support sample evaluation before full-scale production.

• Grade selection matched to cable voltage class, construction and extrusion line.
• Sample supply for trial extrusion and cable testing.
• Technical guidance on processing parameters, storage and handling.
• Custom formulation for specialty cable applications and challenging environments.

Information We Use to Configure Your Solution

To recommend the right grade and prepare a quotation, we need the following project data. The more precisely the working point is described, the faster we can confirm a suitable compound.

Frequently Asked Questions

What types of semi-conductive compounds does HJ Polymer manufacture?

We manufacture conductor shielding, insulation shielding and combined shielding compounds for LV, MV and HV power cables, including bonded, strippable, fast line speed, copper oxidation resistance and super clean grades. We also supply textile tubes for cable and industrial applications.

Can you supply compounds for both thermoplastic and cross-linked cable processes?

Yes. Our range includes thermoplastic shielding compounds for Sioplas and other thermoplastic processes, as well as grades for cross-linked cable constructions. Grade selection depends on the cable design, curing method and extrusion line.

What is your production capacity and lead time?

Our 13 dedicated production lines give an annual capacity of 62,000 tons and a monthly capacity of 5,200 tons. Standard delivery lead time is one week for available grades; custom formulations are scheduled according to the agreed specification.

Do your products comply with international standards?

Our products comply with UL, IEC, GB and other applicable international standards, and our formulations are halogen-free and compliant with RoHS and related environmental regulations. We operate under a certified quality management system.

Can I request samples before placing a production order?

Yes. We supply samples for trial extrusion and cable testing, and our technical team supports grade selection and processing parameters. Sample evaluation helps confirm the compound meets your line and performance targets before full-scale production.

Do you provide customised shielding compounds?

We provide customised solutions for specialty cable applications and challenging environments. Custom formulation is based on the working point, material and production target you specify, and we confirm the specification before production.