The directors of UK-based hydraulic bolt tensioning company Boltight will continue to manage the company at its Walsall base, following the company’s acquisition by Swedish bolting solutions provider Nord-Lock Group in September.

Boltight was founded in 1999 and the company’s hydraulic bolt-tensioning systems have a global reputation for innovation and excellent quality. The Boltight products are used in demanding environments in a multitude of markets, ranging from energy and engineering to construction and mining.

Nord-Lock Group is a specialised bolt- securing and bolt-tensioning systems company and the combined strength of the Nord-Lock wedge-locking washers, the Superbolt mechanical tensioning systems, and the Boltight innovative hydraulic bolt-tensioning systems creates a range of secure bolting solutions.

Nord-Lock states that the strong and unique technologies available through this acquisition will quickly provide benefits to customers in a multitude of markets and geographies. Using the combined distribution outlets now available within the group, each company can quickly develop and support its customers on a worldwide stage.

“We welcome the acquisition and the opportunity of accelerated growth made possible by becoming part of the Nord-Lock Group,” says Boltight MD Fred Heaton.

Nord-Lock Group CEO Ola Ringdahl adds: “We are excited by the acquisition of Boltight, which takes us one step further to achieving prominence in the global business of bolt- securing systems. Boltight’s high-quality product range will open up many interesting business opportunities. We are very pleased to welcome Boltight into the Nord-Lock Group.”

Meanwhile, Boltight announced in August that US multinational conglomerate General Electric (GE) engineers, working on a GE D12 steam turbine, used its hydraulic closure system (HCS) to carry out a blue contact check and assist with final reassembly at French power generation company EDF’s combined-cycle gas-turbine power generation plant in Blénod- lès-Pont-à-Mousson, France.

“This flexible system is now proving increasingly popular for carrying out different types of servicing work in addition to conventional tops on/tops off clearance checks,” says Boltight.

Boltight’s complete system comprises specially designed hydraulic nuts, a hydraulic hose arrangement, a hydraulic pump, spares and a health and safety operating manual. The hydraulic nuts locate on the existing bolts and are screwed down onto the turbine casing. These nuts are linked hydraulically using flexible hoses and quick- acting nipples and couplings. They are connected to an air-driven hydraulic pump.

When pressurised, the closure system stretches the bolts quickly to compress the casing evenly and accurately for performing the clearance, distortion and alignment checks. This saves time during an outage and provides accurate and repeatable results.

The system also delivers significant time savings during final turbine assembly and valve cover tightening. It complements the use of traditional bolt-tightening methods, such as heating and torque, used for turbine disassembly and reassembly, as well as laser alignment methods. The tools can be operated by a customer’s own site personnel with minimal training.

Owing to time constraints during the outage at Blénod, GE’s engineers decided not to perform a conventional tops on/tops off, but rather to carry out a blue contact check to identify potential gaps before final reassembly of the D12. The hydraulic nuts were concentrated on specific areas of the casing that were a cause for concern. In total, 44 hydraulics nuts were used on a horizontal joint that had 80 bolts. Using Boltight’s HCS ensured the whole process took five hours to complete, including engineer training.

Like many of Boltight’s customers, GE Energy chose to rent the HCS rather than buy it. Boltight’s warehouse team can call off a complete kit at short notice, which is configured to GE’s specific requirements. Hydraulic nuts in a range of sizes to fit standard turbines are always kept in stock, together with pumps, hoses and fittings.