Henrob has been operating in the global market for over 20 years and has established itself as the world leader in self-pierce fastening technology with more than 3,500 systems installed world-wide and a European market share of between 50 and 60%.
Self-pierce riveting (SPR) is a method of joining two or more pieces of material using a rivet, however unlike conventional riveting, SPR does not require a pre-drilled hole.
The increasing use of aluminium, magnesium, and high-strength steels whether they be pre-painted, coated or galvanised has led designers to re-examine traditional methods of assembling components. As welding of these materials are difficult or impossible, and assembly using conventional rivets is slow and labour intensive.
Self-pierce riveting increasingly feature in a wide range of industries, as manufacturers face the challenges of extensive use of new materials like aluminium, magnesium, high-strength steels and composites.
The Self-pierce riveting process can join sheets of dissimilar materials, like aluminium to steel, aluminium to magnesium, steel to steel and metals to composites. During the process the self-pierce rivet is driven into the material to be joined at high force, piercing the top sheets of material spreading outwards into the bottom sheet of material, under the influence of an upsetting die, to form a strong joint.
Self-pierce riveting is an automated process requiring no holes that delivers high static strength - similar to or better than spot welding. The process produces a fatigue resistant joint that is up to 30% stronger than spot welding.
As the global popularity of using steel frames for domestic house construction grows, traditional steel fabrication techniques, such as MIG welding, blind riveting, bolting etc are proving labour intensive and costly, damaging and unreliable to meet the increasing volume and quality required in today's demanding market place.
Consequently, manufacturers world-wide are adopting Henrob self-pierce riveting as the primary method of construction for the steel frames, lintels, floor joists and roof trusses that are used in house construction.
The benefits of using Henrob self-pierce riveting over existing methods of joining zinc coated steel are simple, no fumes and no damage to the paint or galvanising. This results in a clean working environment without the need for elaborate and expensive extraction fans.
Self-pierce riveting is a cold process and hence there is no burning of the zinc coating on galvanised steel sheet. This means that the corrosion resistance of the frame is not compromised and there is no need to dress and paint the weld zone.
Also, the strength of the steel is not reduced, as may be the case in the heat-affected areas of a welded frame. No holes are required for self-pierce riveting, therefore there is no swarf generated and there are no subsequent alignment problems. Henrob self-pierce riveting is a fast (around 1-2 seconds to set a rivet) one shot process giving a consistent, high quality joint.