Concrete Screw with Serrated Thread
Hardened concrete screw with an interrupted serrated thread for direct fixing into masonry.
A concrete screw replaces the plug. It goes into a drilled hole in concrete, block or solid brick and cuts its own thread in the masonry, which means the fixing can be removed and the hole reused rather than being committed the moment an expansion anchor is set.
The serrated thread is what makes that possible at sensible torque. Interrupting the thread crest turns each segment into a cutting edge and gives the dust somewhere to go; a continuous thread in concrete packs the flute solid and stalls before the screw is home. The old site lists this item as a concrete screw with secanting, which is the interrupted or serrated thread form.
Why buyers choose it
- Fixes directly into masonry with no plug, sleeve or expansion anchor
- Serrated thread crest cuts rather than wedges, so edge distance is less critical
- Removable and re-usable, which suits temporary works and service fixings
- Available in alloy steel with grade classes up to 10.9
Send the panel or masonry you are fixing into, the drive you run and the head finish and the size will be confirmed against the closest standard before quoting. Samples of this item are free of charge.
Specification
| Standard | ASME, ASTM, IFI, ANSI, DIN, BS, JIS |
|---|---|
| Material | Carbon Steel, Alloy Steel |
| Grade / Class | 4.6, 4.8, 5.6, 8.8, 10.9, SAE J429 Gr. 2, Gr. 5, Gr. 8, A307 A/B, A394, A449 |
| Thread | M, UNC, UNF, BSW |
| Finish | Self Colour, Plain, Zinc Plated (Clear/Blue/Yellow/Black), Black Oxide, Nickel, Chrome, HDG |
| Packing | 15 KGS/CTN, 48 CTN/Solid Wood Pallet |
| Loading Port | Shanghai or Ningbo |
| Minimum Order | 500 kg |
| Payment | T/T, L/C |
| Samples | Free of charge |
| Main Markets | EU, USA, Canada, South America |
Specification as published by Haiyan Ehons Industrial Co., Ltd.. Head diameter, rib pattern and drive size are all quotable against a panel sample.
Technical detail
| Standards | Produced to ASME, ASTM, IFI, ANSI, DIN, BS and JIS references. |
|---|---|
| Material | Carbon steel or alloy steel. |
| Grade class | 4.6, 4.8, 5.6, 8.8 and 10.9; SAE J429 Gr.2, Gr.5 and Gr.8; ASTM A307 A/B, A394 and A449. |
| Thread form | Serrated, interrupted crest for cutting into cured masonry. |
| Finish | Self colour, plain, zinc plated in clear, blue, yellow or black, black oxide, nickel, chrome and hot dip galvanised. |
Problems this screw solves
Expansion anchors split edges
An expansion anchor works by pushing outwards, which is exactly the wrong load near a slab edge. A cutting thread applies far less bursting force.
Plugs are a second part to lose
A plug-and-screw fixing is two components, two sizes to match and two things to drop. A concrete screw is one.
Anchors cannot be removed cleanly
Service fixings get moved. A screw that cuts its thread can be withdrawn and re-driven in the same hole.
Where it is used
- Fixing timber battens and sole plates to a concrete slab
- Mounting electrical trunking, cable tray and pipe clips onto blockwork
- Securing door and window frames into masonry reveals
- Temporary works and formwork bracing that has to come down again
Who buys it
Mechanical and electrical contractors, shopfitters and general builders who fix repeatedly into concrete and want to stop carrying two consumables for one job.
Quality control priorities
Thread hardness is the make-or-break property here: the crest has to stay harder than the concrete for the length of the fixing. Hardness is checked after heat treatment on samples from each batch, alongside a visual check that the serrations are fully formed rather than partially rolled.
Customisation
Colour-coated versions are produced where the fixing head stays visible, and the old site shows this item in several coating colours. The colour sits over the base protective system, so state the exposure as well as the colour when ordering.
How it compares
Against the square hole chipboard screw
Both use the serrated thread idea, but that one is sized and hardened for particleboard. This one is for cured masonry.
Against a through-bolt anchor
A through bolt gives higher characteristic loads. The concrete screw wins on speed, on edge distance and on being removable.
Against a nylon plug and screw
One component instead of two, and no risk of the plug spinning in an oversized hole.
Installation notes
Drill to the stated hole diameter
A concrete screw is sensitive to hole size in a way a plug is not. Use the bit diameter given with the size rather than the nearest bit in the case.
Clear the hole
Blow or brush out the dust. Packed dust is the usual reason a screw stalls short of the surface.
Drill deeper than the embedment
Leave room for the dust the thread displaces, typically at least one screw diameter beyond the embedment depth.
Do not re-drive at high speed
Set the driver to a low speed and a torque limit. Spinning a hardened thread in its own cut destroys the thread it just made.
Frequently asked questions
Does this need a plug or anchor?
Can the screw be removed and reused?
What does secanting mean on the old listing?
Which grade class should I order?
What is the minimum order?
Is a colour coating available?
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View specificationQuote concrete screw with serrated thread
Packed 15 KGS/CTN, 48 CTN/Solid Wood Pallet. Loading at Shanghai or Ningbo. Minimum order 500 kg for this item.