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+86 13143444311
Email：sst@szsst88.com
Fax：+0086-755-27322278
Address：Building 9, First Industrial Zone, Tantou Industrial City, Songgang Street, Baoan District, Shenzhen 518105, Guangdong, China
Type:Button Head Shoulder Screw Stainless Steel
Materials:Stainless Steel
Surface treatment:Plain
Head Type:Button Collar Head
Drive:Hexagon socket (Allen)
Thread:Machine thread
Point:Blunt
Forming:Multi-station heading
Size:M1 M2 M3 M4 M5 M6 M7 M8 M9 M10 M14
Number:27
We make button head shoulder screws in passivated A2 stainless with a domed head, an integral collar, a hexagon socket, a toleranced shoulder and a machine thread, quoting them from M1 to M14. Collar diameter, socket depth, shoulder tolerance and thread come from your drawing.
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ISO 9001:2015 · Manufacturing since 1998 · 8,678+ customers · 89 countries and regions
Made to order – there is no stock catalogue. Each part is produced to your drawing, and production starts after drawing review and first-article approval.
A button head shoulder screw is a stainless fastener with a low domed head, an internal hexagon, a plain shoulder and a machine thread, quoted here from M1 to M14 with Number 27. The head carries a collar — a flat washer face under the dome — so the clamp is spread on a ring wider than the dome, and the shoulder below runs in a bore as the bearing of the joint.
Button collar head. A low dome with an integral flat collar underneath, combining a smooth profile with a real bearing face.
Internal hexagon. A socket cut into the dome and driven with an Allen key.
Shoulder. A plain section that locates or pivots in a bore.
Passivated stainless. A2 grade, uncoated, so the socket and the shoulder are as made.
A button head shoulder screw is used where a fixing has to be smooth to the touch and still clamp a thin panel: appliance doors, instrument covers and small pivots where a cap head edge or a dished panel would be the visible fault.
Three shapes are stacked in the head of a button head shoulder screw, and each takes space from the others. The dome is the outside profile and what makes the head smooth against a hand or a sliding part. The hexagon is cut into the dome, and because the dome is shaped, the socket is shallower than it would be in a flat cap head. The collar sits under the dome and does the clamping.
That makes the collar more important than it looks. The dome alone would bear on a narrow ring, and a narrow ring on a thin panel dishes it. The collar turns that into a flat washer face of a larger diameter, formed in the same strike, so this head form can be tightened on a panel without a separate washer.
The socket is the limiting feature for torque. A shallow hexagon engages less of the key, and on a stainless screw the walls are soft, so the key has to be a good fit and the torque has to be set for the socket rather than for the thread. The same advice as any button head applies: the dome looks generous and the drive inside it is not.
The shoulder below is what the joint uses. It runs in a bore and carries the radial load while the collar clamps around it, and its fit is what decides whether the joint is tight or rattles. A well-made part has a collar that clamps flat and a shoulder that runs true, both cut in the same setup.
The combination is chosen where the head must be smooth and the load must be spread. A cap head spreads as well but has an edge; a low profile head has no edge but no collar; the button collar head is the form that gives both, and it costs a little socket depth to do it.
The recorded range is M1 to M14, with the small sizes used in instruments and the medium ones in appliances and small linkages. Custom lengths up to 2,000 mm are subject to DFM review after drawing submission. For a button head shoulder screw the quotation carries the head diameter, head height, collar diameter, socket size and depth, shoulder diameter and length, and the thread.
| Item | How it is defined | What we control |
|---|---|---|
| Head | Button collar head | Dome diameter and head height |
| Collar | Integral washer face | Collar diameter and face flatness |
| Socket | Internal hexagon | Across flats, depth and corners |
| Shoulder | Plain bearing section | Diameter, tolerance and length |
| Thread | Machine thread | Pitch, length and gauging |
| Material | A2 stainless | Grade and heat number on the certificate |
| Finish | Passivated | Surface condition and film |
Collar diameter is the number to specify first on a thin panel. It is what spreads the load, and it is larger than the dome, so it cannot be read from the head diameter.
Socket depth on a button collar head is worth naming on the drawing. Two suppliers can both make a button head to the standard and differ in how deep they cut the hexagon, and the torque the joint can take follows the smaller one.
Three features define the part: the domed head, the socket and the collar. The first keeps the fixing out of the way, the second is the drive, and the third is what makes the head usable on thin material.
| Feature | What it gives | What it costs |
|---|---|---|
| Domed head | Nothing to catch or cut | Shallow socket |
| Collar | Clamp spread without a washer | Larger head footprint |
| Hex socket | Common key, no cam-out | Lower torque than a cap head |
| Shoulder | A bearing and locator | Fit must be held |
| Passivated A2 | Socket and shoulder as made | Softer than steel; galls dry |
The smoothness is the reason the head form exists. Where a panel slides, a cloth passes over the fixing, or a moving part runs close to the surface, the dome has no edge to catch and the collar still spreads the load underneath.
The trade is the socket. A dome leaves less metal above the hexagon than a flat cap head, and on stainless the shallower socket is what limits the wrench. The key has to be the right size and in good condition.
The recorded finish is passivation with no coating on A2 stainless. On a button head shoulder screw that leaves both functional surfaces as made: the socket keeps the size the key needs, and the shoulder keeps the diameter the bore needs. A coating would narrow one and widen the other.
| Option | How it protects | Effect on socket and shoulder | Typical use |
|---|---|---|---|
| A2 stainless, passivated | Passive chromium oxide film | Socket and shoulder as made | Instrument and appliance joints |
| A4 stainless, passivated | Passive film with molybdenum | Socket and shoulder as made | Marine and medical |
| Steel, black oxide | Conversion film, oiled | No measurable build | Internal mechanisms |
| Steel, zinc plated | Sacrificial zinc | Socket narrowed; re-checked | Indoor general work |
| Steel, nickel plated | Hard barrier deposit | Socket narrowed; shoulder sized | Visible consumer parts |
Where the joint is adjusted or serviced, stainless keeps the socket usable for longer, because there is no soft deposit to rub out of the hexagon. Where the part is wet, A4 is the grade and the shoulder is the surface that matters most.
Where a plated steel version is chosen for cost, the socket has to be gauged after plating. A deep socket that is plated is still usable; a shallow one that is plated is a socket the key will not enter fully.
Three assemblies where a button head shoulder screw is the fixing:
| Where it sits | The screw holds a cover or a door panel where the head must be smooth to the hand and the panel is too thin for a narrow head. |
| When it goes wrong | A narrow head dishes the panel, and a head with an edge catches cloth or fingers. |
| Why it happens | The joint is handled, the panel is thin, and the head is exposed. |
| What we control | Collar diameter and face flatness checked; first article fitted on the panel. |
| Where it sits | The screw forms the pivot of a link where the shoulder is the bearing and the head must clear the moving part. |
| When it goes wrong | The socket rounds, and the link cannot be re-tensioned without replacing the screw. |
| Why it happens | The joint moves, the head is low, and the drive is a key. |
| What we control | Socket depth checked; first article moved through its travel. |
| Where it sits | The screw locates a plate where a smooth head is required and the collar spreads load on a coated surface. |
| When it goes wrong | A proud head marks the panel, and an over-long shoulder holds the plate off. |
| Why it happens | The joint is visible, the surface is coated, and the stand-off is set. |
| What we control | Head height and shoulder length checked; first article fitted in the plate. |
Four reasons that matter on a collar-headed pivot, each tied to what the drawing has to prove:
|
Collar and socket agreed
Collar diameter, socket depth, shoulder tolerance and head height are agreed as one set, because on a button head shoulder screw the head packs three features into a few millimetres. Basis: Collar and socket agreed. |
Formed, socketed, threaded in one route
The dome and collar are formed in one strike, the hexagon is cut, the shoulder sized and the thread rolled within one route. Basis: One route from wire to passivated screw. |
|
Socket and shoulder measured
The socket is checked for depth and the shoulder for diameter after every setup, because both are interfaces the customer feels. Basis: Socket and shoulder measured. |
First article fitted on the panel
The first article is fitted on the customer panel or in the bore, because the collar and the shoulder are only proved in place. Basis: First article fitted in place. |
Shi Shi Tong forms button head shoulder screws on multi-station headers that form the dome and the collar and cut the hexagon, then size the shoulder and roll the machine thread before passivating the parts. The first part of every run is measured on collar diameter, head height, socket depth, shoulder diameter and length before the batch continues.
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Forming a collar under a dome is where the head is decided. The metal has to be pushed outward into a flat annulus while the dome is still being shaped, and a punch that is slightly worn leaves the collar thicker on one side; the head then tightens down unevenly and the shoulder tips in its bore.
What decides whether button head shoulder screws pass is the collar, the socket, the shoulder and the thread. The inspection agreement covers those, and the criteria come from the drawing.
Head and collar on the projector |
Thread gauged per batch |
Hardness checked on the wire |
Salt-spray testing of the grade |
The collar is checked for diameter and flatness, the dome for height, the socket for across flats and depth, and the shoulder for diameter and length. The thread is gauged per batch, and the socket is checked again on the finished part.
The first article is driven with the production key at the joint torque. A socket that measures correctly and rounds on the first tightening is still a part that fails, and only the drive test shows it.
Every shipment of button head shoulder screws is traceable to the wire it was made from and to the passivation batch. The grade and heat number are recorded on the material certificate supplied with the parts, and the inspection records follow the criteria agreed on the drawing.
ISO 9001:2015 |
RoHS test report |
Registered trademark |
Patent: security screw and driver |
With each batch we supply the material certificate, the inspection record for the criteria on the drawing and, where it is listed, the third-party report for the grade. The documents carry the drawing revision and the batch number, so a repeat order keeps the same collar and shoulder geometry.
More than 8,678 customers in 89 countries and regions have ordered from Shi Shi Tong; 87% of orders come from repeat customers and 56% through referrals. Most projects follow the same route: drawing review, first-article approval, then batches checked against that sample. On a button head shoulder screw the first article is fitted on the panel and in the bore, because the collar and the shoulder are both assembly features. Buyers visit during the process to review samples.
|
8,678+
customers served
|
87%
of orders from repeat customers
|
56%
of orders through referrals
|
89
countries and regions shipped to
|
Buyers and quality engineers visit for sample review, process discussion and supplier audits; the visit is arranged around production so the headers and the passivation line can be seen on the day the parts run.
Customer group visit – sample review |
Customer group visit – process discussion |
Customer group visit – factory tour |
Customer visit – project kick-off |
Danish customer – drawing review |
Industry exhibition – meeting customers |
It is a flat washer face formed under the dome. It spreads the clamp load over an area wider than the dome, so a thin panel is not dished.
The dome leaves less metal above the hexagon, so the socket is shallow. Use the right key and set the torque to the socket.
Yes. The collar takes the place of a washer, which is the point of the head form.
Shoulder length for the bearing, and thread length from the shoulder end.
A clearance fit sized to the bore and to the play the joint allows.
Dome diameter and head height, collar diameter, socket size and depth, shoulder diameter and tolerance, shoulder length, thread and the grade.
How a button head shoulder screw project runs from drawing to repeat delivery:
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1
Send the drawing and the panel or bore it fits
|
→ |
2
Collar, socket and shoulder agreed
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→ |
3
First article fitted and driven at joint torque
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→ |
4
Batch production and repeat orders
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Each step is confirmed with you before the next one starts; the drawing revision from the first article is what repeat orders are checked against.
For a quotation, send the drawing with the dome diameter and height, collar diameter, socket size and depth, shoulder diameter and tolerance, shoulder length and thread.
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Head diameter
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Collar diameter
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Socket size
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|
Shoulder diameter
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Shoulder length
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Thread
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Sending a drawing? The form below does not take attachments. Email the PDF, DXF or STEP file to sst@szsst88.com with the part name and quantity in the subject line – the drawing is reviewed and a quotation follows.
+86 13143444311
sst@szsst88.com
