For over 30 years Steve Vick International’s Contract Service teams have been working around the UK, Europe and further afield providing a broad and expanding range of services from cutting large diameter pipes and performing complex gas pipe repair and renewal operations to sealing off abandoned drains and filling all types of underground pipes and voids.
Whilst SVI is known primarily for its work in the field of renewing and repairing underground gas pipes and currently works for all the UK Gas Distribution Networks, recent years have seen customers of the Contract Service division coming increasingly from water utilities, electricity providers, rail networks, civil engineers, construction companies and local councils. This reflects the range of skills and expertise available to solve on-site problems associated with pipe repair, renovation and diversion.
Highly qualified teams to carry out specialist operations
SVI’s Contract Service is a core function of the business with highly skilled teams based strategically around the UK to provide a fast response. For emergency repairs, a rapid call out service is offered 24 hours a day, 7 days a week.
The following project reports give an indication of the range of work being carried out by SVI Contract Service engineers on a regular basis.
REPORT 1. Gas mains diversions
As part of a major highway improvement scheme under construction near Cambridge, SVI is currently involved in the gas main diversion work being undertaken. Contract Service teams are providing grout filling operations where the new 200mm steel gas main runs under the main dual carriageway at several sites, as well as beneath individual junctions with B roads and tracks.
At the road crossing points, the gas main is protected within a 450mm diameter concrete sleeve; the annular space between the main and the sleeve needs to be filled to prevent the sleeve cracking in the future and thus ensure the integrity of the road surface.
Recent projects have involved SVI using a quick-set structural cementitious grout to fill the annular space in two 100 metre sections as well as several shorter 30 to 60 metre lengths. The pre-measured quantity of grout was mixed on-site in SVI’s colloidal screw grout mixer and gravity-fed into the void. The grout can be fed under pressure if required. The work will continue well into 2019.
REPORT 2. Inserting live gas mains remotely under busy highways
Contract Service teams from SVI are carrying out remote live gas mains replacement using the Sealback® technique on a very regular basis.
This technique is a safe and efficient method of replacing short lengths of low pressure ‘live’ main in a traffic sensitive location or where access onto the main is restricted. Replacement is undertaken from a remote position, typically 10 to 13 metres from where the pipe intersects its parent main under the main highway.
A typical recent project involved replacing a 10 metre length of 4” cast iron gas main with 75mm PE situated under a busy road in Staines. The customer was very pleased with the operation, which took just four hours, as it avoided the need to excavate in the main carriageway which would have resulted in lane closure with all the traffic management and reinstatement costs involved.
REPORT 3. Renewing live gas risers in high rise blocks
Renewing gas risers within multi-storey buildings can be a long and costly operation which interrupts customers’ supplies, requires high-cost scaffolding whilst a new service is installed on the outside of the building, and needs access to each property to shut off and relight the supply.
SVI Contract Service offers a safe and cost-saving alternative: the Live Gas Riser Transfer technique allows a new section of steel service to be pieced in between the main and the riser without first decommissioning it.
The technique is currently being used in two 15-storey residential blocks in central Cardiff to renew three 1½” live steel risers which have been leaking at points underground. Nine further risers, whilst not leaking, are being replaced as a precautionary measure.
Using a combination of under pressure tees, under pressure drills, FOAMBAGs™ and fire retardant material, the SVI engineers, working with the GDN, are able to abandon the faulty section of each riser, allowing a new steel service to be pieced in and tied into the main. The whole operation is carried out live, meaning that customers’ supplies are not interrupted and there is no need to gain access to homes.
SVI Contract Service engineers carry out an extensive survey and agree all aspects of the procedure with the client before carrying out Live Riser Transfer. The technique can be used on 1” to 6” diameter low pressure risers and the fire retardant material used provides a 30 minute fire check in accordance with GIS/SER6:2006.
REPORT 4. Sealing off a sleeved gas main under a railway line
A gas mains replacement project in Kent involved SVI Contract Service sealing off the annular space in a 730mm steel sleeve inserted with a 690mm PE gas main running under a railway line. The 140 metre length of pipe was filled with cementitious grout to ensure the integrity of the gas main in the future.
SVI went to site the day before the grouting job to fit ENDSEALS™ on either end of the concrete pipe, leaving fill tubes at ground level. The following day, the quick cure grout was mixed on site in SVI’s purpose built colloidal screw grout mixer and pumped into the sleeve via the fill tubes. Despite the site being well away from the nearest road, SVI were able to carry out the grouting using their diesel powered inject machine and a supply of water from a 30,000 litre tanker.
REPORT 5. Permanently sealing off entire stub ends of live main – remotely
SVI has been carrying out Live Stub End Abandonment for many years but the technique has recently been enhanced with the introduction of E-SEAL™, a system which allows the entire length of the redundant stub, right up to the tier crossover to the parent main, to be abandoned. This avoids any risk of having to return to the main in the future.
Using E-SEAL™, three redundant but live 4” stub ends under a busy road in Hull, each around 3 metres long, were abandoned within a day and saved the customer thousands of pounds in excavation, reinstatement and traffic management costs as well as road closure penalties.
A small excavation is made in the footpath or side road from which the abandonment operation is carried out remotely using SVI’s patented FOAMBAG™ technology. The technique may be used on low pressure main stub ends with diameters from 75mm (3”) to 300mm (12”) with lengths up to 30 metres, but also up to 60 metres if required.
Due to its significant cost-savings, the E-SEAL™ system is gaining approval with a growing number of GDNs.
Mike Hall is SVI’s Contract Development Manager with responsibility for special operations within the division. With over 25 years’ experience in Contract Service, Mike is familiar to many in the gas distribution networks. He has a wealth of skill and knowledge concerning on-site gas pipe repair and renewal operations and has worked not only all over the UK but also around Europe, Scandinavia and the USA.
As Contracting Operation Manager, Caspar Vick manages the day-to-day activities of the ten-strong contracting engineering team which covers the whole of the UK from bases in London, the South West, North West and East. He carries out site audits to ensure that the company’s high operational standards are maintained and works with customers to produce surveys and detailed plans prior to projects.
In addition to working for all the UK gas distribution networks, SVI Contract Service is engaged in operations for the water utilities and the civils sector which is a rapidly expanding market for the company.
For contract service enquiries call Caspar Vick or Mike Hall on 01225 864864