Blog: screw assembly
Deprag's New Adaptive Direct Fastening System is a revolution automatic flow form screwdriving.
The use of flow form screws into two non-drilled sheets requires high down force and high speed to heat and form the hole. It is a complex assembly because to achieve optimal cycle times and proper funnel and thread forming, the down force and feed speed needs adjusted during the various stages of the screw assembly so that the funnel and thread forming can be done reliably.
Traditional systems required numerous pre-tests to determine the timing of the piercing point. Switching parameters too early leads to improper funnel formation and longer assembly times, too late can lead to thread damage.
Deprag's Adaptive DFS is able to sense the exact piercing point as well as other key stages in the screw assembly and switches parameters accordingly assuring:
- automatic adaptation to variances in the screw and part
- the highest process reliability
- shortest possible cycle times
- optimised funnel forming
- reduced set up times
- a more flexible system
- minimise damaged threads
Other features of the Adaptive Direct Fastening System are:
- Active nosepiece jaws that hold the screw firmly until drilling has started
- Adjustable down holder force
- High down pressure applied directly in line with the screw
- Head first screw feeding to minimise damage to the screw’s tip
- Fast interchange of the mouthpiece for minimal downtime
- Lock stroke for underfloor applications
Max Speed: 8000rpm, freely programmable
Max torque: 15Nm, freely programmable
Feed stroke: upto 3000N, freely programmable force and distance
Max Downholder force: 1200N, freely adjustable
Assembly at any angle or upside down.
Complete with industrial PC to set parameters, control the screwdriving and to analyse trends
Innovative Sheet Metal Fasteners
Flow Drill Screws, Flow Form Screws
FDS® screws from EJOT and FFS® screws from Arnold have been around for a while. They offer the benefits of a secure and strong joint from one side between two sheet metals. A big advantage is that they can join dissimilar materials like aluminium, steel and plastics where spot welding is not possible (they are finding more and more applications in the automotive industry where aluminium and other materials need to be joined). They also allow the use of thinner sheets without the use of additional hardware to strengthen the joints (this is making them more popular in the whitegoods industries).
The screws form a hole by high pressure and the speed of the screw, the heated material is then threaded and cools around the screw. The joint is strong, and the unscrewing torque is high. The thread formed is upto 3 times thicker than the sheet metal.
- Heating the metal with high end load and high speed screwdriver
- Penetrating the material
- Forming of the hole
- Forming of the screw thread
- Engagement of the threads
- Final tightening into the cool thread
Advantages for joining sheet metal:
- No swarf or chips
- Stronger joint, higher screw torque possible
- Higher torque means a larger torque window and less chance of stripping
- Screws can be replaced with standard metric screws
- No additional hardware required to strengthen the joint
- High unscrewing torque and vibration resistance
- Possibility of joining thinner materials
- Possibility to join Aluminium
- Can be accessed from one side
- Possibility to join sheets without pre-drilling (in automated applications)
It seems more and more big brand manufacturers are getting their tools made in China or India with substandard materials and design but still charging premium prices.
We recently decided to offer the PB Swiss Tools range of hand tools. They offer a no compromise, top-of-the line range of hand tools, 100% made in Switzerland. They use the highest quality steels, they feel fantastic in your hand, look great (professional) and they last a lifetime. We have uploaded a selection of their various screw assembly related hand tools, but the full range also includes striking tools (mallets, punches, chisels etc) as well as special tools like picks, scribes, awls, hose pluckers and titanium tools.
PB Swiss Tools screwdrivers feature the distinctive Swissgrip handles as well as precise, high quality steel drives.
The Swissgrip handle is made of two components. It feels good in your hand, is slip free, resistant to oils and provides grip even if you have wet hands.
For every Allen key, the tolerances are guaranteed to be less than a hair width. This perfect dimensional accuracy and the hard and tough special alloying make for precise, durable tools.
Available finishes include:
- High quality chrome plating
- Rainbow finish – colour coded wrenches let you find the right key faster
- Gold plated – for corrosive environments or for that extra touch of class?
- Titanium – totally non magnetic for mining & oil & gas applications
T Handle Wrenches:
Okay so we are biased, but these have to be the best T handle wrenches on the market! They are tough, the handles are ergonomic – soft non slip grip and they look the goods.
The ideal tool for fast tightening & loosening of screws featuring the famous Swiss Grip handles. Unlike most other ratchet screwdrivers, these are made to be used every day as you favorite tool, and to outlast your car!
Dirt or dust particles can cause damage to some products or the system into which the sub-assembly will be integrated.
In these situations it is important to avoid abrasion, reduce abrasion or target its removal! These are the basic requirements for screwdriving assembly in clean rooms to ensure the quality of the components to be processed. The DEPRAG CleanFeed Concept provides an overall solution.
Advantage: Integrated design for technical cleanliness. Deprag’s complete program is coordinated for all required individual components, from the feeder to the screwdriver, semi automatic or fully automatic – all from one source.
Function: The screws are stopped in switch position 1 and the residual dirt is removed from the feed parts via vacuum suction. The removed dirt particles are then collected in a filter with transparent inspection window and a replaceable filter element. In switch position 2 the cleaned connection element is fed into the screwdriving module (inline version) or prepared for pick up (Pick&Place version).
The components below can be used to obtain an optimal result:
- DEPRAG HSF sword feeder – vibration free screw feeding – therefore no component friction and minimal abrasion
- DEPRAG Particle killer – dirt particles from the feeder are targeted and removed in-line
- DEPRAG Clean Pick-and Place unit – Screws are fed to to the pick point in the unit, which also has a vacuum to remove particles
- DEPRAG SFM-V vacuum screwdriving module, which fits onto the screwdriver – residual dirt is removed by suction via an additional vacuum source when positioning the screwdriver.