Ace in the hole

Established in 1984, the company's original brief was to sell the deep hole drilling machines manufactured by parent company TBT Tiefbohrtechnik GmbH, but today the company has evolved into an all-encompassing deep hole drilling specialist.  Generally speaking, there are relatively few deep hole drilling companies around – and when you visit an organisation such as TBT, it's not difficult to see why. In terms of the machinery used – everything is large scale and expensive, and from a knowledge-based perspective, propelling drills to depths of 4m and beyond is a prospect that would make even the most battle hardened engineer nervous! But this is exactly the kind of work that TBT embraces and effectively there are four distinct sections of the business – machine tool, sales, subcontract work, tooling and a re-tipping/regrinding service – that complement each other perfectly. The move into the subcontracting world shortly after the company began was an evolutionary one as Mark Ramsay, managing director of TBT UK elaborates: “Often customers would come and see the machines but then report that their order quantities couldn't justify the expense of a purchase. With machine pricing starting at around £150,000 this is quite understandable so we made the decision to set-up a subcontracting facility so we could undertake this type of work. It was definitely the right decision as today it represents over 80% of our total business.” Keep it simple TBT's well-equipped machine shop occupies 26,000ft² of real estate and is home to a number of specialist deep hole drilling machines. Off centre block type work can be accommodated as well as conventional bar work in a wide range of materials from aluminium alloys through to Inconel, composites and Hastelloy. Mr Ramsay believes that with a handling capacity of some 25 tonnes on the shopfloor, there's little in the way of competition in the UK in terms of component size. An important point to make is that TBT as a subcontractor uses TBT Tiefbohrtechnik machines exclusively so it is well-placed to realise the full capability of the machines it sells, but although the equipment is capable of highly complex operations, Mr Ramsay is keen to emphasise that the machines are relatively simple to use. “The skill is in the set-up,” he explains. “Deep hole drilling traditionally is a very labour intensive process but we design our machines to be stable and precise in operation so that once they're set-up, they can run for long periods with minimal intervention. “The set-up still requires specialist knowledge regarding coolant pressures, feeds and speeds and tool life, but we integrate a high degree of process monitoring equipment into our machines so they can run for long periods reliably. In fact it's not unusual for us to leave work running overnight so we need to have absolute confidence in our processes and equipment. ”

Talking terminology TBT has eight gundrilling/deep hole drilling machines at its disposal as well as a recently purchased Churchill Viper VT40-A-400 4m slant bed lathe to undertake turning work. The TBT Tiefbohrtechnik BW250s for example is a 7-axis CNC table type gundrilling machine for off centre work. It can drill to a maximum depth of 1,500mm and can handle diameters from 3mm to 40mm. The TBT B3B-4500 boring machine on the other hand can drill to a depth of 4m encompassing diameters from 20-150mm. This particular machine utilises the BTA/STS drilling system and can accommodate components up to a weight of six tonnes. Nothing is small in this game. Some terminology explanation may be pertinent here. According to Mr Ramsay, gundrilling is a process used to drill holes of up to around 1 inch diameter. Above this, deep hole boring comes into play and whilst both processes use a drill as part of the process, the main distinction is with the way in which swarf and coolant is used. With gundrilling the swarf is ejected via the outside of the drill and coolant is applied through the centre. With deep hole boring – via a system developed by BTA in Germany – the swarf is ejected through the centre of the drill and the coolant is applied under pressure, along the outsides of the drill. Somewhat confusingly, the deep hole drilling process is known by the same name as the company that developed it – BTA. Global tooling provider Sandvik also developed its own system STS (single tube system) so the process is widely known as the BTA/STS system. Flexible working Following the dark days of 2009, TBT is seeing a definite upturn in business levels – particularly in the oil and gas sector. At the moment the company is working a single shift system with overtime and somewhat unusually in the engineering sector, extended hours on a Thursday and Friday until 8pm. “This simply suits our current workload requirements,” Mr Ramsay reveals. “Our customers benefit from the extended hours and we've got the flexibility of introducing weekend working if necessary.” All the deep hole drilling and boring machines manufactured by TBT Tiefbohrtechnik in Germany are built to order which is why leadtimes can be anything up to 12 months, depending on the size/complexity of the machine. Capacity wise, machines are available to drill down to a diameter of 0.6mm but in the standard range holes up to 250mm diameter from solid to 15m deep can be accommodated. “In reality we can go as big as the customer needs,” Mr Ramsay adds. “If there's a requirement to drill or bore holes of say 1m diameter by 20m deep, we can build the machine to do it. “There's a general rule of thumb in this industry. In terms of drill/bore depth, 100 times the diameter is easy; 200 times diameter is getting clever and 300 times is totally specialised.” There's no place like hone Complementing its subcontracting and machine tool business, TBT is also a specialist provider of deep hole drilling and boring tooling and up until a few months ago, the company only sold gundrills from 0.6mm to 38mm manufactured by the parent company in Germany. From 1st May this year however, TBT became the sole UK agent for BTA Tiefbohrsysteme in Germany – a company specialising in the manufacture of deep hole boring tools. The BTA range, which includes a vast array of solid boring heads, trepanning heads, counterboring heads, skiving tools, combination tools and bottle boring tools, complements and extends TBT's own product offering. This is something of a first for TBT – up until now, the company has only ever sold its own tools. Honing is process that often goes hand in hand with deep hole drilling and whilst TBT doesn't sell honing machines per se, its parent company – the Nagel Group has a specialist division that handles the manufacture of honing machines. As part of its subcontract offering, TBT UK has purchased a horizontal tube honing machine from Nagel and plans to install it in its subcontracting facility by the end of the year. “It'll be a useful extension to our range of services,” Mr Ramsay affirms. “At €250,000 it's a serious investment but we want to keep as much of the manufacturing process in-house as possible and having our own honing machine will negate the need to subcontract the process to an external company. It'll be able to hone anything from 25mm to 300mm diameter to a depth of 4m.” So there you have it. TBT has evolved from a seller of deep hole drilling and boring machines to a total solutions provider in every sense of the word. “I think this is our real strength,” Mr Ramsay concludes. “We've invested serious amounts of time and money into making our facility here as self-sufficient as possible and we'll continue to do so. The reality is that customers can get everything they need all under one roof.” TBT UK
www.tbtuk.com