Tel：
+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:Pan Head Stainless Screws
Materials:Stainless Steel
Surface treatment:Plain
Head Type:Pan Head
Drive:Phillips
Thread:Self Tapping
Point:Flat Point
Forming:Single Die Heading
Size:M1 M2 M3 M4 M5 M6 M7 M8 M9 M10 M14
Number:206
We make pan head stainless screws in passivated A2 or A4 with a cross recess and a self tapping flat point, quoting them from M1 to M14. Grade, head, point and thread are taken from your drawing, and the first article is driven into your own sheet.
Watch the factory video·Email sst@szsst88.com
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.
Pan head stainless screws are self tapping screws with a domed head, a flat bearing face and a cross recess, made in stainless steel so that the fixing survives the weather without a coating. The recorded item on this page is stainless with a plain finish, a pan head and a flat point, quoted from M1 to M14 with Number 206.
Pan head. A low dome over a wide flat face, sized to the ISO head form. It covers the hole, bears on the panel and stays inside its own diameter, which is what a row of fixings on a narrow pitch needs.
Self tapping thread. A coarse thread with a sharp crest that forms its own way into a drilled or punched hole, so the joint needs no nut and no pre-tapped thread.
Flat point. A short taper to a flat tip. The hole is made first, by drill, punch or mould, and the thread forms against it; the point guides the first turn rather than piercing the material.
Stainless, plain. Passivated and uncoated, so the alloy is the whole of the protection. There is no film to chip at the head, which on a visible fixing is the difference between a part that ages and one that fails at a scratch.
The head and the cross recess are formed in one heading stroke, so the recess sits concentric with the shank and the bearing face comes out flat. On a pan head stainless screw that matters twice over: an off-centre cross tips the driver, and a driver that tips on a stainless head leaves a mark that cannot be buffed out of the polished surface.
The thread is rolled from under the head to the point, and rolling is what gives it the hardness to cut or form its own thread. Stainless work-hardens as it is rolled, which is the reason a formed stainless screw can tap a hole in a softer material at all.
The grade is the part of the drawing that decides how the screw behaves in service. A2 covers general stainless, A4 adds molybdenum for chloride, and a martensitic grade such as 410 is chosen where the point has to cut harder sheet and corrosion resistance can be traded for hardness. The three are not interchangeable, and the drawing should name one rather than say stainless.
The point is a flat point: it starts in a hole that has already been made. That matters on a stainless sheet joint, because a gimlet point trying to start in stainless will skate and cold-work a polished surface before it bites.
Plain stainless is passivated after forming. Passivation removes free iron left by the heading and rolling tools and rebuilds the chromium oxide film; without it a stainless screw can show rust spots that come from the tooling rather than from the alloy.
The family is quoted from M1 to M14, with M1, M2, M3, M4, M5, M6, M7, M8, M9, M10 and M14 in the recorded range. Custom lengths up to 2,000 mm are subject to DFM review after drawing submission; these pan head stainless screws are normally short, because the thread works in a panel rather than through a stack.
| Item | How it is defined | What we control |
|---|---|---|
| Head | Pan head, ISO form | Diameter, height and face flatness |
| Recess | Phillips cross | Depth and width, bit tried on the part |
| Thread | Coarse self-tapping, full length | Gauged per batch |
| Point | Short taper, flat tip | Checked on the first article |
| Grade | A2, A4 or a martensitic grade | Confirmed on the material certificate |
| Length | From under the head to the point | Measured on the shop plate |
Length is measured from under the head, because that face bears on the panel. On a thin panel the difference between measuring from under the head and from the top of the dome is the head height, and on a screw that is two panel thicknesses long that difference is the whole thread engagement.
The pilot hole is part of the size. In stainless sheet the hole is more critical than in mild steel, because the sheet work-hardens around the hole and a hole that is slightly small will raise the driving torque past what the cross recess can transmit. The hole size is agreed on a sample of the customer’s material rather than taken from a table for another one.
Three features define a pan head stainless screw: the pan head, the cross recess and the stainless body. The first two are standard across the family; the third changes how the screw taps and how the joint fails.
| Feature | What it gives | What it costs |
|---|---|---|
| Pan head | Covers the hole, bears on thin panels | Less bearing area than a flange head |
| Cross recess | Standard bit, cams out before damage | Less torque than a socket of the same size |
| Self-tapping thread | Holds without a nut or tapped hole | Needs the right pilot hole |
| Stainless body | No coating to chip or rust | Work-hardens; galls against stainless |
| Plain finish | Nothing to fill the recess | No added wear resistance |
The work-hardening is the interesting part. When a stainless screw taps into stainless sheet, both sides get harder as they rub, and the driving torque climbs instead of settling. The joint that tapped easily on the first article can fight on the last, and the visible result is a cammed-out cross rather than a thread problem.
Galling is the other stainless behaviour. Stainless on stainless can seize on the first assembly, and a screw seized in a thin sheet tears the sheet before it comes out. Where the joint is serviced, a different grade for the mating part or a dry-film lubricant is the answer, and it is cheaper to specify it than to discover it.
The payback is that the screw does not need a finish. On an outdoor panel, a plated screw loses its coating at the recess and bleeds rust down the face within a season; a stainless screw darkens slightly and stays structurally sound.
The recorded finish is plain, passivated stainless. Nothing is added, so the recess is as formed and the thread is the thread that was rolled — which on a small cross is an advantage, because a few microns of plating is enough to make a bit sit proud and cam out early.
| Option | How it protects | Effect on recess and thread | Typical use |
|---|---|---|---|
| A2 plain, passivated | Passive chromium oxide film | None; gauged as formed | General indoor and outdoor work |
| A4 plain, passivated | Passive film with molybdenum | None; gauged as formed | Chloride, marine and washdown |
| 410 plain | Passive film on a martensitic grade | Harder point, less corrosion resistance | Tapping harder sheet |
| Black oxide on stainless | Dark conversion film | Almost no change | Dark visible assemblies |
| PTFE coated | Dry film lubricant | Film builds; thread re-checked | Joints that seize on assembly |
Coating a stainless screw is usually a mistake. The coating hides the alloy’s own protection, and on a small head the a few microns change the recess fit. Where a dark finish is wanted for looks, a black oxide or a black coating on the head only is the usual compromise.
The honest limit of A2 is chloride. A 304 screw in a coastal or chlorinated environment will pit at the recess and at the thread, where water sits and air is excluded, and the pit is where the screw eventually gives. Where that service is expected, the grade is the answer rather than the finish.
Three assemblies where a pan head stainless screw is the fixing:
| Where it sits | The screw fixes a trim, a bracket or a panel where the joint sees rain and the head is visible on a metal or composite face. |
| When it goes wrong | A plated screw loses its coating at the recess and bleeds rust down the panel; a screw that will not hold strips in the panel. |
| Why it happens | The fixing is outdoors, the head is visible, and the joint is not serviced often. |
| What we control | Grade confirmed on the certificate, thread gauged, head face checked flat. |
| Where it sits | The screw holds a guard, a cover or a fitting where the part is cleaned daily and a coating would trap residue. |
| When it goes wrong | A chipped coating traps product and rusts into a stain on stainless sheet. |
| Why it happens | The environment is wet and cleaned often, and the surface is inspected. |
| What we control | A4 grade confirmed, passivation checked, recess driven with the production bit. |
| Where it sits | The screw fixes a fitting, a cleat or a panel where salt is present and the fixing has to outlast the finish on everything around it. |
| When it goes wrong | A2 pitting at the recess starts a corrosion cell, and a screw that seizes in its hole cannot be removed for maintenance. |
| Why it happens | The service is salt-laden, the joint is exposed, and hardware is replaced part by part. |
| What we control | A4 grade on the certificate, thread gauged, lubricant recommended on assembly. |
Four reasons that matter on a stainless tapping screw, each tied to what the drawing has to prove:
|
Grade, point and panel reviewed together
The stainless grade, the point type and the panel material are reviewed as one set, so a screw that would seize in a stainless panel or skate on a polished face is raised before the die is cut. Basis: Grade, point and panel reviewed as one set. |
Heading, rolling and passivation in one route
The pan head and the cross are formed in one stroke, the thread is rolled to a flat point and the parts are passivated in the same route. Basis: One route from wire to passivated screw. |
|
Thread and recess checked on the part
The thread is gauged per batch, the recess is driven with the production bit, and the driving torque is read in the customer’s own sheet. Basis: First article driven in the customer material. |
First article fixes the setting
The first article fixes the wire heat, die set, roll and passivation; repeat orders are compared against that record. Basis: First article signed off before the batch is released. |
Shi Shi Tong heads these pan head stainless screws from stainless wire on single-die headers that form the pan head and the cross recess in one stroke, rolls the coarse thread to a flat point and passivates the parts before packing. The first part of every run is measured on the head, driven with the production bit and driven into a sample of the customer’s sheet before the batch continues.
|
|
The thread roll is set for stainless rather than for carbon steel. Stainless resists the roll more, and a setting that suits steel leaves a crest that is slightly under-filled on stainless, which is invisible on the bench and shows up as a thread that strips early in a thin panel. The crest is checked on the section of the first article.
What decides whether pan head stainless screws pass is the head, the recess, the thread, the point and the alloy. The inspection agreement covers those, and the criteria come from the drawing.
Head and recess on the projector |
Thread gauged per batch |
Hardness checked on the formed head |
Salt-spray testing of the stainless grade |
The head is checked for diameter, height and face flatness, and the recess for depth and width. Flatness is the dimension that gets assumed: a face that looks flat on the bench can be high at the rim, and a rim-high face bears on a ring and loosens under vibration.
The thread is gauged per batch and the driving torque is measured in the customer’s sheet. On stainless the driving torque climbs as the sheet work-hardens, so the first article is driven into fresh material and the torque recorded, not judged by feel.
The point is checked for taper length and tip flat, and the alloy is confirmed on the certificate. Where the drawing calls A4, the certificate is the only evidence the customer sees before the parts are in service.
Every shipment of pan head stainless 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 for the wire, the inspection record for the criteria on the drawing and, where it is listed, the third-party report for the grade or the passivation. The documents carry the drawing revision and the batch number, so the paperwork can be matched to the parts.
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 stainless tapping screw the first article is also driven into the customer’s own sheet, so the grade and the pilot hole are proved together. Buyers visit during the process to review samples and to see how the heads and threads are formed.
|
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 |
A2 for general outdoor work, A4 where there is chloride or salt, and a martensitic grade where the point has to cut harder sheet and corrosion resistance can be traded.
Yes, with a correctly sized hole. Both sides work-harden as it drives, so the torque climbs and the hole is more critical than in mild steel.
Stainless on stainless galls. A different grade for the mating part or a dry-film lubricant prevents it; once seized, the screw usually tears the sheet rather than coming out.
A flat point for a drilled, punched or moulded hole. A gimlet point would skate on a polished stainless face before it bit.
Plain stainless does not rust in the way steel does, but A2 pitting in chloride is real. It shows first at the recess and at the thread where water sits.
Head form, recess size, thread size and point type, length and datum, the stainless grade and the pilot-hole reference.
How a pan head stainless screw project runs from drawing to repeat delivery:
|
1
Send the drawing or the panel sample
|
→ |
2
Grade, point and thread review
|
→ |
3
First article driven in your sheet
|
→ |
4
Batch production and repeat orders
|
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 head form, the recess size, the thread size and point type, the length and datum, the stainless grade and the panel material.
|
Head form
|
Recess size
|
Thread and point
|
|
Length and datum
|
Stainless grade
|
Panel material
|
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
