Cable Sock Damage & Maintenance
How Can You Tell If They Are Safe To Use?
Inspecting a cable sock is crucially important to ensure safe cable pulling operations, maximum grip strength and grip longevity.
There are a number of variables that can weaken a cable sock that are not immediately obvious on visual inspection. However, there are some important and simple checks that you can do routinely to mitigate product wear, deterioration and potential accidents from happening.
When inspecting a sock, it is critical to know the potential damage and trouble spots. Below is a summary of the types of damage you need to be aware of prior to beginning any pulling project with your cable pulling socks.
Safety is Thorne & Derrick & Slingco’s primary concern. The products Slingco manufacture are safety critical and therefore they have their own fully certified test facility. This allows them to comprehensively test all socks prior to release from design. They design and manufacture to the highest specifications and test to destruction so you can be confident when using a Slingco product.
If you are in doubt about the serviceability of your cable sock, use a new sock! Thorne & Derrick carry large UK stock of cable socks so lead times are short.
The following are some of the types of damage you should be aware of prior to beginning a cable pulling project with your cable socks. If these are observed, replacement of sock should be considered.
The eye of the cable sock is very important. If any damage is found, replace sock immediately. Causes of eye damage include:
• Pulling loads at an angle as opposed to straight line pulling
• Misuse and wear from excessive use
Frayed wires cause the cable sock to weaken significantly. The more wires damaged, the weaker the sock. Causes of fraying are:
• Excessive abrasion while cable is being pulled
• Becoming stuck or snagging during a pulling operation
Rust will weaken the strands of wire that make up the sock. If excessive rust is identified, replace sock. Causes of rust are:
• Socks left in moist conditions or stored damp after water exposure
• Water with high salinity content will cause rusting more rapidly
Bent and broken wires have the same effect as fraying and cause the cable sock to weaken significantly. Causes of this type of damage are :
• Excessive abrasion while cable is being pulled
• General wear and tear over time
The most important factor when using a cable sock to pull wire is to eliminate torsion, or twisting of the cable grip assembly. It is important, when stringing high tension wires for electrical transmission and distribution, to use the proper components to eliminate torsion.
If wires are likely to develop torsion during a pull, line pulling swivels enable the torque to be released, which otherwise could cause damage to the wire or sock.
Advantages of Slingco Swivels include:
Using a cable sock alongside the Slingco swivels to eliminate torsion is crucial
ASSESSMENT OF SUITABILITY
There are many factors that must be taken into account when assessing the suitability of a sock for a proposed application, and when trying to calculate the working load limit.
These include:
➡ Please note: Slingco socks must be double steel banded securely before being pulled.
➡ Slingco cable socks must not be used to their approximate breaking strength. A sensible Safety Factor must always be used. If in doubt contact the manufacturer or distributor that supplied sock.
Thorne & Derrick distribute a complete range of Cable Pulling Products to support the safe installation of LV, MV & HV cables into underground ducts, conduits and trenches – this includes products to enable safe cable drum handling, lifting and support for cables operating at LV, 11kV/33kV medium voltage (MV), 66kV/132kV high voltage (HV) and EHV transmission and distribution cables up to 400kV.
We service the Power Transmission & Distribution industry in the wind, solar, rail, oil/gas, data centre, battery storage and utility sectors.
This includes standard Pulling, Laying & Stringing Products for underground cables, subsea umbilicals and overhead line conductors and also innovations such as Catchblock – a patented overhead line catenary roller system that guarantees that, if a conductor breaks during the stringing process, there will be no need to obtain road or rail possession. This also means reduced need for scaffolding, reduced risk of an accident and an overall more efficient operation.
➡ See Also Further Reading
Earlier this year, Thorne & Derrick welcomed Phil Day from Slingco Limited, the world-leading manufacturer of cable pulling and support socks, swivels, cable protectors, wire rope assemblies and accessories. Phil provided an Offshore Wind focussed company presentation to our Sales Team (pictured left-to-right Sarah Henderson, Carl Cox, Jonathan Hewitt, Phil Day, Jeff Jhanke, Natalie Lundie and Chris Dodds.
Cable Rollers | Duct Rods | Cable Jacks | Cable Lubricant | Duct Seals | Cable Duct
THORNE & DERRICK LV HV Jointing, Earthing, Substation & Electrical Eqpt
VOLTS is our monthly round-up of industry news, projects, videos, technical tips, training information, promotions, webinars and career opportunities from Thorne & Derrick. Take a moment to Follow Us on LinkedIn to receive future VOLTS.
See the archive below.
For Array, Export, Umbilical & Subsea Cable Installations
After 12 months of extensive research and development, Slingco are delighted to launch their new range of cable socks. Bringing you peace of mind with high-volume project capacity, quick availability, full testing details, and forty years experience.
Slingco have developed these marine cable pulling socks for installation of inter-array and export cables for offshore wind farms. The new socks have expanded ranges to suit common cable sizes used in offshore applications and have increased break loads. All of the new socks have a new ‘two over / two under double weave’ on the lattice which tightens up the angle of deflection over the end of the cable.
Slingco offers an extensive range of marine and hose restraint cable socks for onshore and offshore cable installation, including the support of cables inside wind turbines and general cable management.
Slingco also manufacture a speciality heavy duty cable socks, suitable for large underwater pulls. Galvanised steel construction for extremely heavy duty large diameter pulls. Single eye, double eye and lace up. Sizes range from 100mm (4″) to over 355mm (14″).
Marine cable socks are designed, manufactured and tested to exacting standards to ensure safe and reliable operation under the most challenging condition
Thorne & Derrick distribute a complete range of Cable Pulling Products to support the safe installation of LV, MV & HV cables into underground ducts, conduits and trenches – this includes products to enable safe cable drum handling, lifting and support for cables operating at LV, 11kV/33kV medium voltage (MV), 66kV/132kV high voltage (HV) and EHV transmission and distribution cables up to 400kV.
We service the Power Transmission & Distribution industry in the wind, solar, rail, oil/gas, data centre, battery storage and utility sectors.
This includes standard Pulling, Laying & Stringing Products for underground cables, subsea umbilicals and overhead line conductors and also innovations such as Catchblock – a patented overhead line catenary roller system that guarantees that, if a conductor breaks during the stringing process, there will be no need to obtain road or rail possession. This also means reduced need for scaffolding, reduced risk of an accident and an overall more efficient operation.
➡ See Also Further Reading
Earlier this year, Thorne & Derrick welcomed Phil Day from Slingco Limited, the world-leading manufacturer of cable pulling and support socks, swivels, cable protectors, wire rope assemblies and accessories. Phil provided an Offshore Wind focussed company presentation to our Sales Team (pictured left-to-right Sarah Henderson, Carl Cox, Jonathan Hewitt, Phil Day, Jeff Jhanke, Natalie Lundie and Chris Dodds.
Cable Rollers | Duct Rods | Cable Jacks | Cable Lubricant | Duct Seals | Cable Duct
THORNE & DERRICK LV HV Jointing, Earthing, Substation & Electrical Eqpt
Welcome to our industry bulletin – VOLTS.
So what is VOLTS?
VOLTS is our monthly round-up of industry news, projects, videos, technical tips, training information, promotions, webinars and career opportunities from Thorne & Derrick. Take a moment to Follow Us on LinkedIn to receive future VOLTS.
This month, Thorne & Derrick International were delighted to confirm receipt of a new purchase contract order for an offshore wind farm project – this is to supply 33kV Tee Connectors (Nexans Euromold) and Inline Cable Joints (3M ColdShrink) following several rounds of technical qualification, specification and commercial submissions.
Thorne & Derrick’s technical submission for the jointing of the 33kV cables was accepted by the Senior Lead Cable Specialist based upon their 3M QS2000 range – the cable joint designed utilises a unique Cold Shrink delivery system. The 3M Cold Shrink products are supplied pre-stretched on a removable core for efficiency and ease of installation by the jointer with an integral electrical field control device and faraday cage pre-installed in the insulation body to reduce complexity during the installation.
As Approved Vendors to Vattenfall, the Swedish multinational power company, Thorne & Derrick will be supplying a 33kV Inter-Array Cable Accessory Package including medium voltage joints, connectors and cable cleats to support the installation of 19/33 (36)kV Single Core Submarine Cable with 24 Fibres (IEC 60502-2). Read more here.
Pictured Termination: 3M 95EP-631-2 is a 52kV Single Core Outdoor Termination utilising QTIII Technology for 26/45(52) kV Cables. Here’s a pallet shot of a Network Rail project order we have shipped out from Thorne & Derrick in April. The 52kV Cable Terminations manufactured by 3M Electrical utilising their innovative Cold Shrink Technology are Network Rail (NR) certified and PADS Listed as meeting the requirements for installation on their electrical infrastructure.
Thorne & Derrick supply an extensive range of 400V-33kV Rail Cable Accessories & Power Distribution Sytems including feeder pillars to contractors undertaking Low Voltage Power Distribution, HV Electrification & Substations, DC Traction & Networks, OLE and Track Feeder Cable Renewals.
From stock, we deliver HV Terminations to trackside or turbine – whatever the industry, wherever the cable.
Further Reading: Joints & Terminations for Network Rail High Voltage Electrification Projects | PADS Approved
A heritage studio revived for the 21st Century
We are currently working on an exciting project with a heritage film studio, that is undergoing work to expand. The studio plans to expand the complex with new studios and workshops to bring it into modern times and continue use.
Thorne & Derrick are working with the client to provide cable protection and ducting solutions to assist with the expansion project.
Cable protection covers and underground warning tapes are installed over LV, MV and HV power cables in trench and ducted cable installations with high visibility colour providing a visual warning of danger when excavating cables.
Read more about Cable Protection
Thorne & Derrick also stock and distribute a range of cable ducting solutions that are independently certified to British and European Standards and are used extensively for LV, MV & HV substation, highways, housing developments, commercial, retail and industrial infrastructure applications. ➡ View the complete range of Cable Ducts to provide underground cable protection of low, medium and high voltage power cables (LV MV HV) including 11kV and 33kV cable ducting.
Thorne & Derrick are the Specialist Distributor & Stockist for Alroc in the UK for their ranges of manual and motorised Cable Preparation & Jointing Tools for the removal and stripping of outer cable sheath, semi-conductor screen and insulation from LV, MV, HV and EHV power cables.
The ORACL manufactured by Alroc and supplied by Thorne & Derrick enables the cable jointer or user to longitudinally score the peelable semiconductive layer from medium/high voltage cables (typically 33kV up to 1000sqmm) in order to peel it off carefully by hand – this is a key stage of MV HV cable preparation prior to the installation of Power Cable Accessories including joints, terminations and connectors.
The ORACL screen scoring tool covers most “easy-strip” peelable semicon thicknesses by having adjustable scoring depths of 0.4, 0.6, 0.9 & 1.1mm – contact us for prices, stock availability or further information.
Anatomy of 33kV Cable
1 Aluminium Conductor with Water Blocking Protection | 2 Semiconducting Screen | 3 XLPE Insulation | 4 Semiconductng Screen | 5 Copper Wires Screen | 6 Copper Tape | 7 Water Blocking Tape | 8 PE Sheath
See Also from Alroc
Stocked & Supplied by Thorne & Derrick
Read | Chris Barker |132kV Transition Cable Joint
Thorne & Derrick are Specialist Distributors to the Oil & Gas industry of LV, MV & HV Cable Installation, Jointing, Substation & Electrical Equipment – since 1985 we have worked closely with EPC’S, E&P and related companies ensuring the highest levels of safety, reliability and maintainability of LV HV cable and power systems.
T&D hold the largest European stocks of 3M Hazardous Area Cable Accessories LV HV – this includes Cold Shrink and Scotchcast joints, terminations and abandonment kits for safe use in potentially explosive atmospheres up to 33kV.
Specialist Cable Joint & Repair Systems include submersible, hydrocarbon and fire resistant solutions for marine and offshore power, control and instrumentation cables.
We provide expert technical support and supply from a multi-million pound stock holding:
Selected Article | Repairing Damaged Cables, Cable Sheath & Jackets
Supporting Articles
Shelf-to-Shelf
This April we shipped-out 50+ Resin-type low voltage power and instrumentation cable joints with hydrocarbon resistant Scotchcast resin suitable for installation in Zone 1/2 flammable gas atmospheres according to ATEX Directive – picked from the Bristol warehouse shelf destined overnight to the continental shelf of the North Sea.
If you need to joint, to terminate or to connect LV or HV cables, either onshore or offshore, whatever the cable, wherever the location: Thorne & Derrick can help.
Scotchcast Stocks | Jointing Systems for all types of Industrial Cables
Jonathan Hewitt, Key Account Sales Engineer at Thorne & Derrick, enjoyed attending the Dogger Bank Wind Farm ‘Meet the Buyer Event’ organised by NOF. The event included presentations by Dogger Bank, Port of Tyne and North Star Renewables. The networking lunch and one-to-one meetings created a great opportunity to meet project managers and stakeholders to learn more about opportunities within the project.
About the Event
Dogger Bank Wind Farm and its Tier 1 Contractors are committed to the development and growth of a competitive UK supply chain. The meet the buyer event was held to showcase contract opportunities during the operations of this flagship UK development.
More about Dogger Bank
The Dogger Bank O&M Base is being constructed at the Port of Tyne and is due to be completed in Q4 2022. The project is the UK’s first HVDC connected wind farm and will feature the world’s first unmanned HVDC offshore platforms. North Star Renewables has been contracted to provide four Service Operation Vessels to the project. One rotation of GE’s Haliade-X turbine can power a UK household for two days. 277 units of the 13MW and 14MW turbines will be used on Dogger Bank.
Dogger Bank is a joint venture between SSE Renewables (40%), Equinor (40%) and Eni (20%).
Jonny Hewitt from Thorne & Derrick with Noman Shabir from Ellis Patents at the Dogger Bank – Meet The Buyer Event.
This month we are hosting a prize draw to win a PFISTERER special edition Centenary Book. We are delighted to celebrate 100 years of PFISTERER with the history of their role in the energy industry, dating back to 1921. Connecting power for the future.
Enter the prize draw here
PFISTERER meets future challenges with the knowledge that comes from one hundred years of experience. This expertise has developed continuously with advances in technology. Numerous innovations and patents continuously drive our growth with further investment in R&D planned for 2022 and beyond. Read more about our established relationship: Thorne & Derrick | Product Training With PFISTERER
Mane Contract Services are committed to working with their client partners to help create a greener and cleaner future. For over 20 years, they have provided project staffing solutions to the complete project lifecycle across all Energy sources. Mane have an extensive project and client portfolio across both cable manufacturing & installation, working across UK, EMEA, APAC and USA.
Stephen Stuart and his team at Mane and they are looking to expand their network within the Wind Energy Industry;
– HV Engineering & Installation – 33kV, 132kV, 155kV, 220kV, 400kV
– Commissioning Engineering / Commissioning Management
– Installation Management & Package Management
– Grid Connection and Cable Installation
– Project Management / Construction Management
– Client Representation
– Site Management & Support
– Document Control & Management
– Project Planning / Scheduling– Project Controls Management
– Health & Safety Management
If you are recruiting for yourself or looking for a new career move within the Renewables sector then please get in touch +44 (0) 1923 470 724 or email: [email protected]
For more information – visit their jobs page; https://www.mane.co.uk/energy/
With a network of international offices around the world and a large dedicated team of specialist Account Managers and Head Hunters, Mane are well placed to support your career development or recruitment requirements around the globe.
Thorne & Derrick distribute the most extensive range of Low & High Voltage Cable Installation & Electrical Distribution Equipment to the Power Transmission & Distribution industry in the onshore and offshore wind, solar, rail, oil/gas, data centre, battery storage and utility sectors – this includes Joints, Terminations & Connectors to enable the installation of low, medium and high voltage power cables into underground trench or duct.
Key Product Categories: Connectors, Joints & Terminations MV HV | Cable Preparation & Jointing Tools | Duct Seals | Cable Transits | Cable Cleats | Cable Glands | Electrical Safety | Arc Flash Clothing & Protection | Cable Pulling | Earthing & Lightning Protection | Feeder Pillars
Main UK Stockists for: 3M Electrical, PFISTERER Connex, Nexans Power Cable Accessories (Euromold), Alroc, Ellis Patents, ABB, Roxtec, Cembre & CATU Electrical.
Alroc manufacture a range of cable jointing tools for the removal and stripping of outer cable sheath, semi-conductor screen and insulation from LV, MV, HV and EHV power cables – this includes precision engineered manual and motorised cable installation and preparation tools for Power, Transmission & Distribution cables.
The ORACL by Alroc enables the cable jointer or user to longitudinally score the peelable semiconductive layer from medium/high voltage cables (typically 33kV) in order to peel it off carefully by hand – this is a key stage of MV HV cable preparation prior to the installation of Power Cable Accessories including joints, terminations and connectors.
The Screen Scoring Tool has an adjustable scoring depth of four different lengths (0.4 / 0.6 / 0.9 / 1.1 mm) and is lightweight in design.
Screen Scoring Tool Capacity
Spare Part
LSO – Spare blade for peelable semiconductor
Associated Tool
DSP – Peelable semiconductor lifter
MVS – Stop for tools
Screen Scoring Tool Dimensions
| Part Number | Diameter | Tool Capacity | Dimensions | Packaging | |||
| Scoring Depth | Min Remaining Length | Length | Width | Height | |||
| Alroc ORACL | 10 – 100 mm or 0,394 – 3,937 inch | 0.4 / 0.6 / 0.9 / 1.1 mm or 0.016 / 0.024 / 0.035 / 0.043 inch | 10mm | 135 mm 5,315 in |
55 mm 2,165 in |
35 mm 1,378 in |
Box |
Thorne & Derrick | Stockists & Distributors for the Alroc Range of Cable Jointing & Preparation Tools
Contact us with your Enquiry.
Thorne & Derrick protect substation engineers, asset managers, SAPS, cable jointers, overhead linesmen and utility workers with PPE and safety equipment: this includes insulating gloves, voltage detectors, insulating matting and portable earthing to ensure worker safety when carrying out repair and maintenance on LV-HV switchgear, transformers, substations and turbines.
All our Cable Connection & Energisation Accessories including Medium & High Voltage joints, terminations, connectors and cleats are tested to the latest international standards and supporting ranges of professional installation tools are stocked to reduce incident, accident and downtime to plant and people.
Published 12 Mar 2026
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