For almost 20 years S&D Services, of Chard Junction, Somerset, has been clearing blockages from, removing root intrusions in, replacing and repairing drainage systems across Somerset and Dorset. Having started as a franchise for to one of the UK’s well known, country-wide operators, S&D now operates independently from its idylic rural setting, undertaking projects mainly for industrial and commercial clients with occasional smaller domestic works, primarily on insurance claim operations.
Established in 1986, S&D Services started with a small crew and operated in the Somerset and Dorset area only. During the early 1990’s, as lining technology started to take a serious hold on the drainage market in the UK, the company expanded it operations with lining works becoming an increasingly important part of the operation.
By 2005 S&D lining revenues had become some 50% of the company’s turnover, largely as follow-on work from initial blockage, clearance and survey operations. The number of crews has also increased to five comprising 10 operators in all with two crews being utilised full-time on lining operations.
Drainage works over the years have comprised operations on pipelines from 75 mm up to as much as 1,200 mm diameter, with the most common being around diameters of 300, 375 and 400 mm. The larger diameter works have tended to occur around one-off unusual jobs over various lengths, but generally clients include local building companies and structural engineering firms. In more recent times S&D has also spread its area of operation to include projects as far apart as North Wales and the Southeast of England.
As part of its growth, and in the changing climate of client requirements, S&D also undertook and achieved ISO 9001/2000 quality certification; is a member of the UK’s Investors in People scheme; and is registered with the CITB. The company also ensures that all personnel undertake the necessary training and hold relevant certificates with all operating staff being CSCS Health & Safety Card Holders; Certificated in High Pressure Water Jetting Safety; NVQ qualified in Drain Installation; Confined Space Works certificated (through Thames Water); Tower Scaffold Erection Certificated; and Brawoliner Certificated, with training undertaken at the manufacturer in Germany. Crews are also fully trained and qualified in application of the requirement of the New Roads and Street Works Act 1999 for signing, lighting, guarding and excavation. S&D is also an approved contractor for Wessex Water and various other local authorities.
SURVEY AND CLEANING
As well as lining works, the company also undertakes all of its own CCTV survey work, in support of the main drain clearing operations, with crews fully trained in operation and reporting requirements. Using mainly Telespec-manufactured equipment, now sourced through Radiodetection Ltd’s camera operations alongside Pearpoint camera equipment, S&D operates two crawler-mounted mainline CCTV units and two pushrod smaller diameter systems as well as a CamScan portable CCTV unit. This range of equipment enables S&D to survey pipelines from as little as 75 mm diameter up to 1.5 m diameter. The company occasionally undertakes some of it own modifications to these systems, such as wheel replacement on the crawlers, to enable it crews to operate in circumstances that might otherwise be difficult to access with the standard systems.
S&D also owns and operates its own vacuum tanker/jetter as well as a smaller Flexian ‘Envirojet’ low-noise, LPG-powered, high-pressure jetter, along with several other common diesel powered jetter units. These units cover the requirements for pipe cleaning and root removal across the company’s operating diameter range.
In support of the lining and cleaning services offered by S&D, the company also undertakes pipe bursting operations where a trenched replacement is not feasible and lining is inappropriate or simply not possible. The system used for this is the Miniburst unit, a rod based hydraulic pipe bursting system originally designed by Clearline Services and currently available through Pipe Equipment Specialists Ltd. The Miniburst systems is capable of working in pipe diameters from 100 to 150 mm with just two operators. It can burst common pipe materials such as clay, pitch fibre etc and usually utilises snap-together segmental polyethylene pipe as the replacement material. Working between manholes or two small access points the system quickly and efficiently replaces a damaged or ageing pipe, particularly in limited access and residential situations or where existing structures such as walls or fencing form a barrier to traditional open cut works.
With lining comprising some 50% of S&D’s revenues, choosing the right lining materials has always been an important part of the company’s strategy.
For its larger diameter, long length (manhole to manhole) CIPP lining operations S&D uses felt lining materials manufactured by Applied Felts Ltd in conjunction with thermosetting or ambient cure resins from Germany-based MC-Building Chemicals.
For thermo-cure CIPP lining the company has adopted an installation process which means that the requirements for a large boiler unit on site is eliminated in favour of utilising a smaller van-mounted water heating system. Once the lining material has been inverted into the host pipe with cold water, this water is drained from the liner and replaced with compressed air to hold the liner material against the host pipe inner surface. The smaller water heating unit is then used to warm the curing water to the required temperature prior to entering the inflated liner. As the heating can be done quickly, curing time can be reduced significantly and the energy requirement is also reduced, making the whole process more efficient. Once curing is completed the liner is again surveyed and lateral connections remade.
The Applied Felts liner is used from around 225 mm diameter upwards although if circumstances are favourable the material may be used at smaller diameters.
For smaller diameter, long length lining works S&D uses, exclusively, the Brawoliner system comprising KOB-manufactured lining materials and MC-Building Chemicals resins. The Brawoliner system uses a seamless lining textile fabric that is applicable to pipes from 75 to 255 mm diameter, with wrinkle free installation around 90o bends. The system is generally compressed-air inverted from an inversion drum and can be used as an ambient or hot water cured installation. If hot water curing is to be utilised a water inversion technique using an inversion tower is normally used.
The Brawoliner system is designed to answer some of the more pressing environmental problems with more established lining system resins across Europe, and does this by using environmentally friendly resins. In response to these environmental concerns other more commonly used resins have in some cases and countries been banned from use. Brawoliner has also been presented with an award for innovation in the Rhineland region of Germany on the basis that it was specially designed to meet the latest environmental standards, as well as being manufactured to ISO9002 standard.
Using MC-Building Chemicals epoxy, polyurethane and silicate resins S&D also installs localised permanent repairs. The system is generally used to install localised repairs of between 1 and 5 m long , although within S&D the system has been used for single installations of up to 15 m long in the right operating conditions and circumstances.
Commenting on the company’s lining capabilities Steve Sampson MD of S&D Services said, “We have used Brawoliner and Applied Felts materials with MC-Building Chemicals resins for a several years. Why? Because they give us the consistency of performance and a confidence level that company’s like ours require when dealing with major utilities, industrial and commercial clients. This of course also has the advantage that when we do complete domestic installations, the ‘industrial’ quality of the product is carried through to the residential market. Our suppliers are always there to support our work and have always willing to discuss new application scenarios and circumstances as and when they arise.”
Ian Clarke, NoDig Media Services,