Product Introduction

NLL-4 Bolted Type Tension Clamp (4-U-Bolt Aluminum Strain Clamp)

Suitable for conductor cross-sections of 150–240 mm², this premium NLL-4 Bolted Type Tension Clamp represents our highest specification engineering design. It is explicitly developed for the heavy tension mounting and secure anchoring of large-cross-section conductors on 10kV/33kV overhead power lines and heavy-duty utility trunk networks.
Manufactured from extra-thick, high-grade aluminum alloy and secured by four high-strength U-shaped bolts, it delivers maximum mechanical clamping force and can stably withstand massive dynamic tension. This makes it the preferred premier choice for bolt-type strain clamps on heavy-capacity, long-span distribution networks.

Technical Parameters

Check the professional structural parameters below to select the exact 4-Bolt Aluminum Bolted Strain Clamp dimensions that perfectly fit your ACSR / AAC conductor specifications:

Model	Applicable stranded wire diameter (mm)	Main dimensions(mm)		Number of U-shaped screws	Nominal breaking load(kN)	Quality(kg)	Material
Model	Applicable stranded wire diameter (mm)	Main dimensions(mm)		Number of U-shaped screws	Nominal breaking load(kN)	Quality(kg)	Material
		M	C
NLL-1	8.0～12.0	16	18	2	40	1.5	Aluminum Alloy
NLL-2	11.0～16.0	16	18	2	60	1.8	Aluminum Alloy
NLL-3	15.0～20.0	16	27	3	70	2.5	Aluminum Alloy
NLL-4	19.0～24.0	18	30	3	90	3.5	Aluminum Alloy

Detailed technical parameters

NLL-4 Bolted Type Tension Clamp

NLL-4 Conductor Compatibility: Precision-calibrated for large-diameter overhead lines, effortlessly accommodating an applicable stranded wire diameter range of 19.0–24.0 mm (ideal for high-capacity 150-240mm² ACSR configurations).

4-U-Bolt High-Torque Mechanical Specs: Features an advanced structural design with an M18 bolt size and a 30mm channel width (C value). Utilizing 4 heavy-duty U-shaped bolts, it distributes massive, balanced holding power uniformly along the conductor.

Heavy Tensile Holding Capacity: Delivers a certified nominal breaking load of 80 kN, offering superior slip resistance and mechanical integrity against fierce outdoor wind loads and cable thermal contraction.

Product Features

Features of Bolted Type Tension Clamp

Key Engineering Features of NLL Bolted Strain Clamps

High-Conductivity Premium Aluminum Alloy: Cast as a single heavy-duty piece from top-grade aluminum alloy, ensuring an optimal combination of lightweight ergonomics, dense structural toughness, and outstanding current-carrying capacity.

Waved Groove & 4-U-Bolt Synergy: The interior features precision-milled cable grooves conforming tightly to standard conductor profiles. When secured by the 4-U-bolt heavy locking mechanism, it maximizes physical contact friction, providing an incredibly secure grip without flattening outer aluminum strands.

Substation-Grade Corrosion Defense: The aluminum body undergoes an advanced surface anodized passivation process, coupled with premium hot-dip galvanized fasteners. This provides elite protection against heavy outdoor moisture, acidic smog, and coastal salt-spray oxidation.

Utility-Certified Safety Performance: Fully complies with international and national technical standards for electric power fittings (GB/T 2314, GB/T 2315, DL/T 764). Thoroughly verified via rigorous factory tests for temperature rise and mechanical ultimate tensile load for utility-grade grid infrastructure.