The manufacture of BigHead fasteners depends on one core requirement � the ability to weld a thin, large-diameter metal head to a stud or collar, at a strength equal to that of the metal of which it's made. This central skill is at the heart of the BigHead product range, and with the company's latest automatic welding machine now in full production, a major increase in production capacity is on-line, helping to produce the company's range of over 1,200 variants.
Designed and built by BigHead's technical staff with the help of BWP Technical Services Ltd., the Twinhead is capable of producing two sizes of BigHead simultaneously at a production rate of some 3,000 per hour, at zero defect levels. The machine requires no labour, and is believed to be 'unique' in the world. "We invented the BigHead 40 years ago," says BigHead's MD Brian Giddings, and we are unaware of anyone, anywhere, even capable of knowing how to start the design. The machine consists of two auto-welders built on a single chassis; each is fed by two bowlfeeds, with feeder tracks leading directly to the eight weldheads on each side. Each weld, incorporating up to six weld cycles at varying current and hydraulic pressure, takes less than half a second. Three separate sensor systems check up to six parameters, to give the weld a tailored melt and optimum grain structure. This allows for studs from M4 to M8 thread to be welded to heads from 15mm to 38mm in diameter, either in mild or 316 stainless steel.
"The Twinhead represents a huge investment for a small, specialised company like BigHead," says Brian. We're very proud that we produced it entirely from our own resources and BWP's know-how. We've learnt a lot from the whole process, the next one will definitely cost us a lot less! Further technical details are available direct from the company, and visitors to the BigHead factory are welcome, given reasonable notice.
Contact - Terry House terryhouse@bighead.co.uk
Tel. (+44)1202 574601
Website: www.bighead.co.uk
October 2006 |
|
 |
 |
 |
| The Twinhead is fully software-controlled; this picture shows the
touchscreen control panel and RH multi-head welding area |
 |
 |
 |
| The eight weld heads on each side are fitted with individual head and
stud guides relevant to specific head/stud diameters. |
 |
 |
 |
| The stud bowl feed for the RH side of the Twinhead, feeds an M6x12
stud to be welded to the B15 head - used in the Bentley Continental |
 |
|