Dead End Clamp Types and Selection Guide for ADSS, OPGW, and Conductors

Dead end clamps are used to reliably and tensilely anchor overhead conductors or ADSS/OPGW optical cables at terminal, corner and other positions. However, the most difficult part in actual selection is the excessive types and confusing names. Once the mechanism or size is wrongly selected, it is easy to cause slippage, damage to the wire/sheath, and even accelerate corrosion. This article will explain the "type" in a clear path: by clamping mechanism → application object → tension grade → model system, allowing you to quickly select the correct type, match the specifications, and avoid common pitfalls.

What Is a Dead End Clamp?

A dead end clamp (also known as a dead-end clamp, strain clamp, or tension clamp) is essentially a "terminal anchor" for the line: when the conductor or optical cable is tightened, it is responsible for reliably clamping this tension and transmitting the force to the pole/trestle/gear system through connecting components (such as shackles, U-bolts, connection plates, etc.). You can think of it as an "anchor point" on the line, whose function is not to support weight but to lock the tension and fix the direction.

It is usually installed at locations that need to withstand significant tension or change the direction of force, such as terminal poles (start and end points of the line), corner poles where the line turns, large spans (crossing rivers/roads/valleys), branches/leads (where the main line branches off to a secondary line or connects to equipment), and in some projects, at splice points/section change points (for easier tension control and maintenance). The common feature of these locations is that the line tension needs to be "caught" and cannot continue to be borne by the suspension gear.

Dead End Clamp vs Suspension Clamp

One-sentence analogy:
A dead end clamp is the anchor that stops and transfers line tension, while a suspension clamp is the support that hangs the line and lets it pass through.

Key differences (quick comparison):

Dead End Clamp Types Overview

Before diving into details, it helps to see all dead end clamp types at a glance. The same "dead end" function can be achieved by very different designs, and picking the wrong type (or the wrong size) is the fastest path to slip, jacket damage, strand damage, or corrosion issues. Use the overview below to quickly match the right type to the right system and installation reality.

Dead End Clamp Types - Quick Overview Table

Type by Holding Mechanism (Wedge / Bolted / Compression / Preformed)

Type by Application (Conductor / ADSS / OPGW / Guy)

A simple mapping that works for most projects:

• ADSS Dead End Clamp → commonly wedge dead end or preformed/helical dead end
• OPGW → commonly preformed/helical dead end systems (often with dedicated protection components)
• AAC/AAAC/ACSR (conductor) → commonly compression dead end (higher load) or bolted/mechanical dead end (tool-friendly)
• Guy wire → guy dead end grips/clamps (system-specific)
   

Important warning: a guy dead end is not the same product as a conductor dead end-they may look similar, but they're designed for different materials, load paths, and hardware interfaces.

Type by Tension Level

"Tension class" is a practical way to match the dead end to the actual mechanical demand created by:

• Span length (longer spans = higher tension demand)
• Wind / ice load (environment can dominate load)
• Safety factor / design rules (utility standards vary)
• Angle severity (larger line angle = higher resultant load at the structure)

When to step up to a higher tension class (checklist):

• Larger line angle (e.g., stronger direction change)
• Long-span crossings (roads, rivers, valleys)
• Heavy ice zones / high wind corridors
• Critical structures where failure consequence is high
• Higher required holding strength or stricter utility specs

Type 1 - Wedge Dead End Clamp

A wedge dead end clamp is used mainly for ADSS fiber optic cable, ABC aerial bundled cable, and some insulated or covered lines. The core idea is self-locking: the clamp holds the cable using wedge inserts, and the grip increases as line tension increases, as long as the cable outer diameter is within the specified clamping range.

In a typical distribution job, crews work on a crowded pole line with limited space and a short to medium span. They need a fast install with minimal tools and a compact fitting that connects quickly to the pole hardware. That is exactly where wedge dead ends are commonly chosen.

How Wedge Dead End Clamps Work?

Main components

Body, the housing that guides and supports the wedges

Wedge inserts, the gripping parts that lock onto the cable jacket

Bail or clevis, the connection point to linking hardware such as a shackle or bracket

Liner or insert when included, a protective layer to reduce jacket damage or tune the grip
 

Self-tightening principle
When tension is applied, the cable tends to slide, which pulls the wedge deeper into the body. This increases contact pressure and friction, so higher tension creates a stronger grip. This only works correctly when the clamp is matched to the cable outer diameter. If the size is wrong, the clamp can slip or damage the jacket.

Common Mistakes with Wedge Type

• Choosing the wrong outer diameter range causes slipping, jacket damage, and rework
• Installing the wedge the wrong way or using the wrong wedge set causes weak grip and uneven pressure
• Not cleaning the cable surface allows grit to abrade the jacket and leaves wear marks
• Poor alignment creates uneven gripping and increases the risk of deformation or slip
• Applying tension too quickly can seat the wedge poorly and scuff the jacket
• Using mismatched linking hardware can introduce bending loads and accelerate wear
• Skipping final inspection means problems show up after commissioning rather than during installation

Type 2 - Bolted Dead End Clamp

A bolted dead end clamp is a mechanical termination that grips the conductor with bolts. It is commonly used when compression crimping is not convenient, or when the project wants a clamp that can be removed for maintenance, rework, or temporary setups. The core rule is simple: torque creates clamping force, but it is not a case of tighter is always better. Correct torque gives stable holding without damaging strands, crushing liners, or creating uneven pressure that leads to slip.

How Bolted Dead Ends Grip Conductor?

Main components

Clamp body, the main housing that supports the conductor

Keeper, the top piece that closes the clamp

Bolts, the fasteners that apply clamp force

Groove, the shaped channel that matches conductor size

Liner or padding when used, a layer that improves grip and protects strands
 

How it holds
Bolted dead ends hold through a combination of friction and geometric seating. The groove and keeper help position the conductor, while bolt torque applies contact pressure. With correct sizing and torque, the clamp maintains holding strength without strand damage or long-term loosening.

When to Choose Bolted Dead End Clamps?

Choose a bolted dead end clamp when the job needs speed, flexibility, or rework capability, such as:

• Emergency repair and restoration work
• Sites without hydraulic pressing tools
• Installations that prefer a reusable, service-friendly termination
• Temporary rerouting, test spans, or trial sections
   

Typical conductor coverage
Bolted dead ends are commonly used on AAC, AAAC, and ACSR conductors, especially in distribution applications. Always match the clamp groove and size range to the specific conductor and stranding.

Type 3 - Compression Dead End Clamp

A compression dead end clamp is a crimped termination for overhead conductors, widely used when the project requires higher holding strength and long-term reliability. This type is known for strong, stable performance, but it is also the most process-dependent option. Correct tools, correct dies, correct pressing sequence, and proper surface preparation are what make a compression dead end succeed.

How Compression Dead Ends Work?

Compression dead ends use a sleeve or compression tube that is pressed onto the conductor to create a permanent mechanical connection. Once compressed correctly, the sleeve transfers tension from the conductor into the clamp hardware and can withstand higher loads than many removable designs.

Engineers often describe these terminations as full-tension or partial-tension. Full-tension designs are intended to carry the full mechanical demand of the line section, while partial-tension designs are used where only a defined portion of the rated breaking strength is required by the project specification. The key point is that the expected holding requirement must match the product design and the project rule.

Type 4 - Preformed Dead End

A preformed dead end grip is a helical termination that uses pre-shaped spiral rods to distribute stress along a longer contact length. Instead of concentrating pressure at one point, the helical design spreads the load more evenly, which reduces the risk of strand damage on conductors and jacket damage on fiber cables. This type is commonly used in ADSS and OPGW projects, and it is also used in certain conductor termination systems where long-term mechanical stability is a priority.

What Is a Preformed Dead End Grip

Preformed means the rods are factory-formed into a spiral shape that matches a specific cable diameter and construction. In the field, installers follow the markings and wrap the rods into place until the grip seats correctly.

Typical components include:

• Helical rods that wrap around the cable and provide the holding force
• A thimble or loop that forms the connection eye and protects the loop radius
• Linking hardware when required, such as a shackle, clevis, or link
   

Preformed Dead End for ADSS

For ADSS, the goal is secure holding without damaging the cable jacket. Preformed dead ends are often selected when projects want more even pressure distribution and clear tension-class matching for different spans and loads. Depending on the design and the project conditions, additional protection may be required, such as jacket protection elements or reinforcement accessories for higher load locations.
 

Special Dead End Clamp Types

This section is here to prevent the most common mistake in selection and purchasing: applying conductor logic to fiber cable hardware, or using a fiber cable solution on a conductor system. ADSS, OPGW, conductors, and guy wires may all use the term dead end, but the load paths, materials, and protection needs are not interchangeable. Use the application-specific guidance below to match the right dead end type to the right system.

ADSS Dead End Clamp Types

ADSS terminations are usually built around two mainstream options: wedge dead ends and helical preformed dead ends. The right choice depends on installation reality and mechanical demand.

Wedge dead end

• Installation speed is usually faster and more compact
• Often works well for short to medium spans when OD is well controlled
• Maintenance and replacement can be convenient on many designs
• Risk profile depends heavily on correct OD matching and surface cleanliness
   

Helical preformed dead end

• More jacket-friendly in many cases because contact length is longer and stress is distributed
• Tension level coverage is usually clearer because products are commonly offered in light, medium, and high classes
• Often preferred for higher tension or more demanding spans where long-term stability is important
• Requires careful alignment and correct seating based on markings
   

Practical recommendation logic

Choose wedge type when the priority is fast installation, compact hardware, and typical distribution spans with stable OD control

Choose helical preformed when the priority is higher tension capacity, long-term reliability, and better stress distribution on the jacket
 

OPGW Dead End Types

OPGW terminations are typically more complex because OPGW is both a mechanical and an electrical component. Hardware selection may involve protection and interface considerations beyond simple gripping, and assemblies can include protection elements, dedicated connecting components, and system-specific designs.

What readers should know to ask for:

Whether the system needs protection against strand damage and vibration wear

Whether special interface hardware is required for the tower attachment point

Whether the assembly must support grounding and electrical performance requirements
 

RFQ fields to request for OPGW projects:

OPGW construction and specification, including strand design if available

Cable outer diameter

Required mechanical holding or rated tensile load

Tower type and the attachment interface, including clevis style and pin diameter

Any project requirements related to protection, corrosion environment, or documentation
 

Guy Wire Dead End Types

Guy wire systems exist to stabilize poles and structures, so the load path and hardware ecosystem are different from conductor or ADSS systems. Guy wire is typically steel strand, often with galvanization requirements, and terminations connect into anchors, turnbuckles, and guy attachments rather than conductor fittings.

Selection fields to include:

Guy strand diameter

Galvanization level and corrosion environment

Required holding strength and safety factor requirements

End fitting and connection interface, such as thimble, eye, or shackle size

Anchor hardware and overall guy assembly configuration
 

Dead End Loop Clamp Types

A loop style dead end forms an eye that connects to a shackle, clevis, or yoke plate. Loop terminations are chosen when the project needs a clean hardware interface and reliable load transfer through a defined connection point.

Common loop options and trade-offs:

• Bolted loop clamp is fast to install and can be service-friendly, but torque control and surface condition are critical
• Compression loop is strong and stable for long-term high-load use, but requires pressing tools and is not easily reworked
• Preformed loop is jacket-friendly and distributes stress, but model selection and installation alignment require care
   

Straight-Line vs Side-Opening Dead Ends

Straight-line designs are installed along the conductor path, typically requiring the conductor to be positioned into the clamp in the standard installation sequence. Side-opening designs allow the conductor or cable to be placed into the clamp from the side, which can be helpful when space is limited or when installation constraints make standard feeding difficult.

Selection notes to include:

• Space and access at the structure, including clearance to open and tighten hardware
• Maintenance and replacement workflow, especially in crowded pole lines
• Directionality and orientation, ensuring the clamp seats correctly with the actual line pull direction

How to Choose the Right Dead End Clamp Type?

This is the selection section readers actually use to buy and specify hardware. Present it as a decision tree plus a simple selection form so they can copy the fields into an RFQ. The core rule is always the same: application object, size, required strength, available tools, environment, then accessories and interface.

Selection principle
Object → Size → Tension or strength → Tools → Environment → Accessories

Step 1 - Identify the Cable or Conductor Type

Start by choosing what you are terminating. This decides the viable dead end families.

Select one

• AAC, AAAC, ACSR conductor
• ADSS cable
• OPGW cable
• Guy wire
   

Most common type recommendations

• AAC, AAAC, ACSR conductor: compression dead end for higher load and long-term reliability, bolted dead end for field-friendly and serviceable work
• ADSS: wedge dead end for fast installation on typical spans, preformed helical dead end for higher tension classes and more jacket-friendly distribution of stress
• OPGW: preformed or system-specific OPGW dead end assemblies that match the cable construction and tower interface
• Guy wire: guy grips or guy dead end systems designed specifically for steel strand and guy assemblies
   

Step 2 - Confirm Diameter or Size Range

Size is the fastest way to eliminate wrong options. A clamp cannot hold correctly if the diameter or conductor specification is outside the intended range.

Why size comes first
Holding performance is driven by contact geometry. Wrong diameter leads to slip, jacket damage, strand deformation, or poor long-term stability.

Field measurement tips

For ADSS and OPGW, measure outer diameter with a caliper when possible and confirm with the cable datasheet

For conductors, confirm the exact conductor designation and stranding, not only the area number

Avoid relying on nominal names or verbal descriptions because different constructions can share similar labels
 

Step 3 - Define Required Holding Strength

Selection is not complete until the mechanical requirement is clear.

How to think about strength
Working load is what the line experiences in service. Rated tensile load is what the hardware is designed to withstand. The project specification defines the safety factor and the required margin.

What to ask the owner or designer

Required holding strength target and whether it is defined as working load, rated load, or a percentage of rated breaking strength

Span length and loading assumptions such as wind and ice

Line angle at the structure and whether the structure is terminal or angle

Any utility standards that control acceptance testing, slip criteria, or proof load requirements
 

Step 4 - Consider Installation Tools and Crew Skill

Tool reality often decides the best type as much as engineering does.

Tool matrix questions

Is a hydraulic compression tool available, and are dies and charts confirmed for this sleeve

Is a torque wrench available and required for mechanical clamps

Is there a short outage window that favors faster installation

Is the crew trained for preformed installation alignment and marking
 

Practical type guidance

No hydraulic tools and fast installation needed: wedge for ADSS, bolted for conductor

Highest reliability and long-term performance priority: compression for conductor, preformed for ADSS or OPGW

Frequent maintenance or potential rework: bolted designs are often easier to service than permanent compression

Step 5 - Environment and Corrosion

Environment affects material choice, coating level, and long-term inspection needs.

Typical selection tendencies

• Coastal salt fog or high corrosion zones: higher corrosion protection, careful mixed-metal compatibility, and stronger coating requirements
• Industrial pollution areas: prioritize coatings and surface durability to reduce corrosion initiation
• Heavy ice or high wind corridors: higher tension class and higher mechanical rating, plus system-level vibration considerations
• Sand and dust environments: avoid designs that trap grit against the jacket or conductor surface, and emphasize cleaning and inspection
   

Step 6 - Accessories Needed

Dead end selection is incomplete without the interface hardware.

Common accessories

Thimble

Shackle

Yoke plate

Clevis

Link
 

Quick Decision Table

Use a table like this on-page so readers can match their situation in seconds.
 

Dead End Clamp FAQ

What does RBS mean for dead end clamp holding strength?

RBS means rated breaking strength of the conductor or cable. For dead end clamp selection, holding strength is often specified as a percentage of RBS, which tells you how much of the conductor's breaking capability the dead end is required to hold without slipping or failing. The correct target percentage depends on the system and the project standard, so use the utility or design specification to confirm the required grip level before choosing the dead end clamp type and size.

How to prevent dead end clamp slipping?

Prevent slipping by controlling three things: correct type, correct size, and correct installation force. First confirm the dead end clamp is designed for the actual application and material, then match the conductor size or cable OD to the clamping range, avoiding boundary sizing. For bolted dead ends apply the specified torque evenly in steps, and for compression dead ends follow the die chart and press sequence. Keep contact surfaces clean and aligned with the line pull direction, and mark a reference point so any movement can be detected early.

How to prevent ADSS jacket damage from a dead end clamp?

ADSS jacket damage usually comes from OD mismatch, contamination, or uneven seating. Choose a dead end clamp with a clamping range that matches the measured cable OD, keep the cable and clamp contact surfaces free of grit, and tension the line gradually so the clamp seats smoothly. Avoid twisting and off-center loading, and inspect for sharp edges or incorrect wedge inserts. If the span or tension level is higher and jacket protection is a priority, a preformed helical dead end is often a better choice because it distributes stress over a longer length.

How do dead end clamps resist corrosion and galvanic corrosion?

Corrosion resistance comes from material selection, coatings, and avoiding harmful mixed-metal contact. Common approaches include aluminum alloy components for compatibility with aluminum conductors, hot-dip galvanized steel for general outdoor protection, and stainless steel for aggressive environments. Galvanic corrosion can occur when dissimilar metals are in contact with moisture, especially in coastal or industrial areas, so match materials where possible and use isolation methods when needed. In RFQs, specify the corrosion environment and required coating level so the dead end clamp and all linking hardware are protected as a system.

What standards apply to dead end clamps?

Applicable standards depend on whether the dead end clamp is for conductors, ADSS, OPGW, or guy wire, and which utility or region you are supplying. In practice, standards and project specs define required tests such as proof load, slip performance, ultimate tensile strength, and sometimes corrosion testing. The most reliable approach is to ask for the exact project standard and acceptance criteria, then confirm the supplier can provide matching documentation such as test reports, material certificates, and installation instructions.

What is a straight line dead end clamp?

A straight line dead end clamp is a dead end clamp designed for a straight pull condition where the line tension is in line with the conductor or cable path. It is typically used at terminal structures or section points when the line does not change direction, so the load is mainly axial rather than a combined angle load. Selection still follows the same rules: match the clamp type to the application, match the size to conductor or cable OD, and confirm the holding strength and hardware interface for the structure.