The manufacturing process of a rivet rod is comprised of various operations:
- The round steel is cut to length in relationship to the conveyor’s width specification.
- If the rod’s centre is to be secured to one or more central traction beltings by rivets, those areas are heated, forged/flattened and punched. For Super-Flex ® and High-Flex centres the heated rod is subjected to compression which forms a hot bulbous mass at the belting attachment areas.
- These hot areas are formed into the shape of our proprietary Super-Flex ® and High-Flex centres which give the rod an increased cross-section in its weakest spot, the attachment area/rivet holes of the centre beltings.
- No central area heat treatment takes place if the rod is to be secured to the belting by means of central retaining clamps/clips.
- The rod ends are then heated prior to the forge/flattening process, which also forms the rod’s convexity and, if applicable, the rod is cranked, then punched with optionally spaced rivet holes.
- If required with heavy duty applications, the rod can be hardened and stress relieved to maintain consistent material properties over its full length.
The centre to centre distance between a rod’s outer rivet holes is called the ‘Stickmark” or ‘Stokmaat’ which for Broekema Holland & Broekema U.S.A. determines a conveyor’s overall width.
Broekema requires a rod’s overall length measurement (rod with) to determine the conveyor´s overall width. It is very important to refer to either the stickmark or the rod width when ordering replacement rods.
- Spring steel: This steel quality is cold drawn and available in classes B, C or S. It offers a very high hardness & wear resistance. Subject to rod pitch & rod stress loading, these steels are suitable in many normal to heavy applications.
- Hot rolled steel 55Si7 & Boron alloyed steel are suited to post hardening and a stress relief process.
They are good for extreme load applications. The Boron-alloyed steel is well suited to applications which involves welding-on metal pins, steel risers/flights, etc.. Whilst heat treating & forge flattening reduces the base material’s strength, the rod’s strength will be consistent over its total length, if the rod is hardened & stress relieved.
Weight saving is possible by using fiberglass rods. Their ends are enclosed in special end pieces which allow riveting to the belting.
Twin rods divides the belt pitch over 2 rods, offering narrow rod clearances which can be further reduced by means of rod coverings. To avoid Twin-rod wear, special Twin-rod conveyors are usually friction or cam driven.
We offer also vulcanized rods for trash extraction, crop protection, flight profiles, etc..