I. Project Background

The Guida Paper Mill factory is located within the Binyang County Migrant Workers Entrepreneur Park in Nanning City. The project required the construction of a 35kV substation to meet the high-reliability power supply needs of paper production. Key requirements for the project, scheduled for delivery in May 2025, included:

Main transformer capacity of 9250kVA (4000kVA × 2 + 1250kVA × 1)

Installation of 5x 35kV high-voltage switchgear panels, 20x 400V low-voltage switchgear panels, and a secondary security & protection system.

Adaptation to the temperature and humidity environment of the industrial park (daily average humidity ≤ 95%).

II. Customer Pain Points

High Power Supply Reliability Requirements: Paper production lines require a continuous and stable power supply. Traditional distribution equipment with insufficient breaking capacity posed a risk.

Space and Timeline Constraints: Limited space in the park's existing electrical room necessitated rapid deployment and a solution accommodating future expansion needs.

Environmental Adaptability Challenges: The high temperature and humidity environment of Nanning (95% daily average humidity) easily causes condensation and corrosion in electrical equipment.

III. Proposed Solution

A customized substation solution was provided to address the pain points:

Core Equipment Selection

High-Voltage System: Utilizes KYN61-40.5 armored withdrawable switchgear.

✅ Enclosure assembled from aluminum-zinc coated steel plates, Protection Degree IP4X (Dust and splash water protected).

✅ Screw-driven trolley mechanism + mechanical interlock design, meeting the "Five Prevention" safety standards (GB3906/DL/T404).

Low-Voltage System: Configures SWGGD-type fixed switchgear.

✅ Rated current 6300A, short-time withstand current 50kA (Compliant with GB7251.12 standard).

✅ Dedicated ZMJ busbar clamps (made of PPO flame-retardant material) enhance dynamic stability.

Key Technical Design

Environmental Adaptability:

Low-voltage cabinet bottom heat dissipation slot design, forming a bottom-to-top air circulation path (Operating temperature range -15°C ~ +40°C).

High-voltage cabinet composite insulated busbars + flame-retardant insulation sleeves, preventing moisture and condensation.

Efficient Delivery:

SWGGD cabinet structure utilizes modular C-section pre-production, shortening the installation cycle by 30%.

Universal cabinet 20-module mounting holes, compatible with mainstream components like DW45/CW1.

IV. Customer Value

Safe and Reliable Operation

High-voltage switchgear mechanical interlocking prevents misoperation; low-voltage switchgear high breaking capacity (50kA) ensures grid stability.

Busbar clamps possess V0 flame-retardant rating (PPO material), reducing short-circuit fire risk.

Optimized Whole-Life-Cycle Cost

Modular structure supports rapid future capacity expansion.

Cabinet door hinge pins + U-shaped rubber-plastic seal design achieve IP30 protection degree, reducing maintenance frequency.

Efficient Delivery Ensures Production

Successful commissioning on schedule (May 24, 2025), supporting the timely startup of Guida Paper's production line.