15‑34KV/55A ANSI Bushing with Tension Terminal for Oil‑Immersed Distribution Transformers

Introduction

What is 15‑34KV /55A ANSI Bushing with Tension Terminal

1. Meet ANSI dielectric withstand requirements for 15kV‑34kV medium‑voltage distribution class
2. Continuous rated current 55A, stable temperature‑rise performance under full‑load operating conditions
3. Reliable mechanical pre‑loading function provided by tension terminal to maintain internal assembly compression
4. Multiple shed options to meet different creepage demands for pollution‑level environments
5. Oil‑compatible sealing materials resistant to long‑term immersion in transformer mineral oil
6. Standard tank opening and mounting dimensions for interchangeable replacement
7. Capable of enduring operating vibration, thermal cycling and short‑circuit mechanical force

General Technical Specification Table for 15‑34KV /55A ANSI Bushing

Notes:

1. Models suffixed with ‑13K refer to modified top terminal thread specification; non‑suffix versions adopt standard M12*1.75 thread.
2. Shed quantity directly determines total creepage distance. Select more sheds for coastal, dusty and heavy‑pollution application sites.
3. Tension terminal and earthing terminal come as standard components for this bushing series. Protective cover is optional accessory.
4. Tank opening dimension follows ANSI unified standard for matching distribution transformer tank cut‑out.

Core Advantages of 15‑34KV /55A ANSI Bushing with Tension Terminal

1. Tension‑Terminal Locking Structure Enhances Assembly Stability

   The built‑in tension terminal applies controlled axial pre‑tension to the internal conductive stud. It keeps gaskets and fitting assemblies under consistent compression status. Even under repeated thermal expansion and contraction caused by transformer load changes, the structure resists loosening, effectively reducing oil‑leakage risk which is a common failure point for medium‑voltage transformer bushings.
2. Multiple Shed Options for Variable Pollution Conditions

   A full range of shed quantities from 4‑shed up to 17‑shed provides flexible creepage‑distance selections. Engineers can pick suitable shed configuration according to site pollution class. Compact 4‑shed and 7‑shed versions fit general inland areas, while 11‑shed,15‑shed and 17‑shed heavy‑shed types are ideal for salt‑spray coastal zones and heavily‑polluted industrial districts.
3. ANSI Standard Interchangeable Mounting Dimensions

   Tank opening size, flange layout, thread specifications and overall dimensions comply with ANSI industry standards. When old bushings require maintenance or replacement, operators can install qualified alternative units without cutting or reworking transformer tank structures, shortening equipment downtime and lowering spare‑part management cost.
4. Complete Accessory Configuration

   Standard supply includes tension terminal, earthing terminal for safety grounding connection. Optional protective cover shields top connection hardware against rain, dust and external mechanical impact, extending service life of exposed connection parts.
5. Reliable Outdoor Porcelain Insulator Performance

   High‑strength electrical porcelain insulator features good anti‑aging, anti‑tracking and weather‑resistant performance. It withstands ultraviolet radiation, temperature fluctuation and outdoor atmospheric exposure for long‑term distribution‑network operation.
6. Wide Compatibility for Global ANSI‑Standard Projects

   This bushing type is widely used for North‑American pad‑mounted transformers, pole‑mounted distribution transformers, and export‑oriented transformers delivered to Latin America and other regions adopting American power standards. Both original‑equipment manufacturing and aftermarket replacement demands can be satisfied.

Typical Application Scenarios

• Oil‑immersed pole‑mounted distribution transformers for 15kV,18kV,25kV,34kV ANSI power grids
• Pad‑mounted transformers for municipal and industrial power distribution
• Transformer manufacturing for export to ANSI‑standard countries and territories
• Repair, overhaul and spare‑part replacement of existing ANSI‑spec transformers
• Auxiliary power transformers for industrial facilities, mining and energy projects

Product Selection Guide

1. Confirm rated voltage: choose 15kV,18kV,25kV or 34kV according to transformer system voltage class. Rated current for this series is 55A.
2. Determine shed quantity and required creepage distance based on site environmental pollution level. Select more sheds for coastal salt‑fog or heavy‑dust locations.
3. Verify thread specification of top terminal: distinguish standard M12*1.75 version and ‑13K modified thread variant to match customer connection hardware.
4. Check tank opening dimension, mounting height H, h1 and h2 values to guarantee sufficient internal and external installation clearance on transformer tank.
5. Confirm requirement for optional protective cover for top connection protection.
6. Ensure tension terminal and earthing terminal are included as standard components for assembly and safety grounding.

Installation & Maintenance Best Practices

1. Carry out full visual inspection before installation. Check porcelain body for cracks, chips or surface damage. Verify tension terminal, earthing terminal, gaskets and metal fittings are intact without deformation.
2. Clean transformer tank mounting surface thoroughly, remove welding slag, paint residues and debris to achieve full flat contact between bushing flange and tank wall.
3. Position bushing aligning with tank opening, pass conductive stud through tank hole, then install and tighten the tension terminal at lower end with proper torque. Do not over‑torque; excessive force may damage porcelain insulator, while insufficient torque leads to gasket loosening and oil leakage.
4. Complete earthing connection via earthing terminal according to power‑system safety requirements. Install optional protective cover if specified.
5. After installation, perform oil‑tightness test to check for oil seepage around mounting flange area.
6. During periodic maintenance work: inspect porcelain surface contamination condition, check flange position for oil stains, verify tension terminal fastening status and earthing connection reliability. Replace aged sealing gaskets once leakage traces are discovered.
7. Avoid heavy mechanical impact to porcelain insulator during transportation, lifting and field installation.

Common Operational Issues & Root Causes

Conclusion