By Rachel Salisbury – Rachel has worked as an Application Engineer for 3M in the Electrical Markets Division for 18 years advising customers and end-users on applications and specifications for 3M’s range of LV MV HV cable accessories for solutions in rail, construction, oil and gas and the renewables markets.
uploaded by Chris Dodds - Thorne & Derrick Sales Marketing Manager
A question I get asked a lot, is what is cold shrink and how can it benefit me, my cable installers and my project costs?
Is it just a more expensive option with the gimmick of unravelling a core?
The answers are simple; there are multiple benefits for cold shrink, both financial and product benefits, it’s well-researched and a tried and tested solution from 3M for cable installations and a must-have in flammable areas of work including hazardous area locations with potentially explosive atmospheres.
3M cold shrink is made from either EPDM (Ethylene-Propylene-Diene-Monomer) or silicone rubber, that is expanded onto a spiral core. After the cold shrink tube has been placed over the joint or cable termination end, this inner spiral is pulled out. The insulating tube then contracts to its pre-stretched size and shrinks onto the cable, exerting constant radial pressure for the lifetime of the joint or termination.
Cold Shrink Offers the Maximum Mechanical Protection
Cold shrink products have a 45+ year track record of performing exceptionally well in indoor and outdoor environments, including under harsh conditions.
The silicone material conforms well to cable bends, which ensures long term reliability against moisture ingress, or voids within the installation. It is shows excellent performance in the following environments:
i. Refineries
ii. Coastal environments
iii. Altitude
iv. Dusty environments eg. solar power plants, wind farms
v. Vibrations eg. railroad, subway
vi. Underwater environments
vii. Overhead joint applications
* Data based upon U.S. failure data of U.S. manufactured 3M Cold Shrink Medium Voltage Cable Accessories between 2009 and 2012.
Initially heat shrink may provide a good environmental seal obtained with the application of adhesive and mastics by the cable jointer included in the MV termination or cable joint.
However, over time the cable can expand and contract due to temperature changes. During a rise in temperature, a heat shrink material may be able to expand at the same time.
But, if the cable contracts due to temperature decreases, either because it returns to its initial temperature or it drops below its initial temperature, a rigid heat shrink material may not shrink with the cable, therefore leaving a void between the cable and the cable accessory.
This void can allow moisture and contamination from dust, chemicals, etc. to get into the cable accessory, which may accelerate the likelihood of failure. Long term expansion and contraction of the cable could create cracks and splits in a rigid heat shrink installation.
Tracking is defined as a process that produces localised irreversible deterioration on the surface of an insulator, resulting in the loss of the insulating function by the formation of a conductive path on the surface of the insulator.
The cause of tracking is when voltage, moisture and contamination exist together, and it will eventually lead to an electrical failure because it erodes enough of the material so that there is a continuous conductive path from high voltage to ground. When there is a continuous conductive path, there is a short from the high voltage to ground.
Silicone is an excellent track resistant material and is hydrophobic, repelling water and making the insulator self-cleaning which results in a dryer surface and lower leakage currents. 3M outdoor cable terminations include rain sheds which disrupt any wet leakage paths that occur in industrial environments and also allows the creepage distance of the termination to be much shorter.
Wind Farm | 3M Cold Shrink Joints On High Voltage XLPE 34.5kV Cables. Image J Neimeyer.
UV can damage the material of the termination, which creates cracks where contamination and moisture can be trapped and increase the likelihood of tracking.
All 3M terminations are produced from high performance Silicone, which is designed to be inherently UV resistant.
EPDM and Ethylene-vinyl Acetate (EVA) need additives to make them UV resistant, which over time can dissipate and reduce the UV resistance of the material.
Thorne & Derrick | Stockists & Suppliers of 3M Electrical Products
The time difference is significant with Heat Shrink taking double the time to install than Cold Shrink.
Other factors to be taken into consideration are delays in days to obtain hot permits, training and the costs of risks, for example: liability of fire, explosion, shutdowns and the associated insurance to cover these.
Multiply up the installations per annum this could provide a real cost saving for companies.
In summary, you get what you pay for, a premium product yet when looking at the total cost of ownership, this product comes out on top. Cold Shrink – yes, it’s the Real Difference.
Established since 1985, T&D International based in the UK distribute the most extensive range of LV, MV & HV Cable Jointing, Terminating, Pulling & Installation Equipment – contact us today for a competitive quotation.
Key Products : MV Joints & Terminations, Access Chambers, Cable Cleats, Duct Seals, Cable Transits, Jointing Tools, Feeder Pillars, Cable Duct, Earthing & Lightning Protection, Electrical Safety, Cable Glands, Arc Flash Clothing Protection & Fusegear.
Distributors for : 3M, Pfisterer CONNEX, Nexans Euromold, Elastimold, Catu, Roxtec, Emtelle, Centriforce, Lucy Zodion, Alroc, Cembre, Prysmian, Ellis Patents, ABB & Furse.
Mark Henderson (CATU) and Natalie Lundie (Thorne & Derrick International)
Mark Henderson (Sales Engineer) at CATU Electrical visited Thorne & Derrick offices today to discuss with Natalie Lundie (Supply Chain: Marketing Lead) how we can work together on some joint marketing initiatives to further increase sales lead generation.
CATU Electrical manufacture electrical safety equipment for LV HV and EHV applications including switching and maintenance work on low and high voltage electricity switchgear and cable systems – the range includes voltage detectors, substation life saving kits, insulating sticks, insulating gloves and insulating matting.
Mark has recently took on a new role at CATU Electrical as a Electric Vehicle Safety Equipment Specialist and has requested the help of T&D to build a marketing campaign around products specific to the EV industry.
💡 Blog Electrical & Hybrid Vehicles | Improving Electrical Safety for the EV Industry
Ready for the Revolution? Thorne & Derrick can support the implementation of electrical safety precautions with automotive manufacturers, dealership networks and garage repair specialists – products specifically designed to prevent electrocution.
Mark Henderson Sales Engineer at Sicame Distribution UK comments, “Thorne & Derrick are the UK’s largest stockist and distributor for CATU Electrical – supplying Safety Equipment for underground, overhead line and substation safety on LV, MV and HV cable networks including the renewables industry.”
T&D’s Sales Engineers have excellent product knowledge and are supported by CATU Electrical with ongoing training. Their team are friendly and technically astute going “above and beyond” – offering a proactive customer service which also includes joint product demonstrations and field support. The sales team are strongly supported by a marketing team whose expertise and strengths are SEO, social and digital marketing,” Mark adds.
➡ Look out for our Q&A with Mark about EV Electrical Safety.
CATU Electrical Safety Equipment
Stockists & Suppliers of Electrical Safety Equipment
Pictured: Brugg Outdoor Cable Terminations From Transformer to GIS
Images Courtesy of: Frikkie Pieterse – High Voltage Cable Jointer 132kV
Brugg Cables stands for integrated solutions, competence and Swiss quality in power distribution and data transmission.
High Voltage Cable Accessories for Polymer Cables
High Voltage Cable Accessories for Oil-filled Cables
Subscribe now to our POWER NEWSLETTER– a monthly email circulation packed with news, projects, videos, technical tips, training information, promotions, webinars, career opportunities and white papers.
Includes access to our popular JOINTERS BLOG with contributions from utility professionals, linesmen and cable jointers working on MV HV EHV cables and overhead lines typically at 11kV, 33kV, 66kV and up to 132kV.
15,000+ Subscribers. ➡ 
Image Courtesy of : Remus Bidireac – 11/33kV Cable Jointer at Schneider Electric
Pictured: Pfisterer Connex Substation Cable Terminations
Outgoing circuits are single cable/phase. Incoming cable feeders are multiple cable/phase, 2 each from 60MVA transformers 3 per phase from 90MVA transformer. All rated 33kV – current rating is circuit/cable dependant as different size and construction cables used.
➡ Special thanks to Martin Winterburn and Scott Crowley.
T&D are Main Distributors & Stockists for the Pfisterer range of Medium Voltage Power Products including Connex Plugs, Cable Jointing Tools, Sicon Connectors, Surge Arresters and Electrical Safety Equipment.
Thorne & Derrick Specialist Electrical Distributor
Established since 1985, T&D distribute the most extensive range of LV, MV & HV Cable Jointing, Terminating, Pulling & Installation Equipment – contact us today for a competitive quotation.
Key Products : MV Joints & Terminations, Cable Cleats, Duct Seals, Cable Transits, Underground Cable Protection, Jointing Tools, Feeder Pillars, Cable Duct, Earthing & Lightning Protection, Electrical Safety, Cable Glands, Arc Flash Protection & Fusegear.
Distributors for : 3M, Pfisterer, Nexans Euromold, Elastimold, Catu, Roxtec, Emtelle, Centriforce, Lucy Zodion, Alroc, Hivotec, Cembre, Prysmian, Ellis Patents, ABB & Furse.
Subscribe now to our POWER NEWSLETTER– a monthly email circulation packed with news, projects, videos, technical tips, training information, promotions, webinars, career opportunities and white papers.
Includes access to our popular JOINTERS BLOG with contributions from utility professionals, linesmen and cable jointers working on MV HV EHV cables and overhead lines typically at 11kV, 33kV, 66kV and up to 132kV.
15,000+ Subscribers. ➡
Image Courtesy of : John Penny – Cable Jointer / Director at CableTec Services
Pictured: Pfisterer Plugs Terminating 33kV XLPE Cables Into Toshiba GIS Shunt Reactor
Thorne & Derrick International, based in the UK, are Main Distributors & Stockists for the Pfisterer range of Medium Voltage Power Products including Connex Plugs, Cable Jointing Tools, Sicon Connectors, Surge Arresters and Electrical Safety Equipment.
Subscribe now to our POWER NEWSLETTER– a monthly email circulation packed with news, projects, videos, technical tips, training information, promotions, webinars, career opportunities and white papers.
Includes access to our popular JOINTERS BLOG with contributions from utility professionals, linesmen and cable jointers working on MV HV EHV cables and overhead lines typically at 11kV, 33kV, 66kV and up to 132kV.
15,000+ Subscribers. ➡
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