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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:Pan Head Tapping Screw
Materials:Steel
Surface treatment:White Zinc Plated
Head Type:Pan Head
Drive:Phillips Cross
Thread:Self Tapping Thread
Point:Sharp
Forming:Single Die Heading
Size:M1 M2 M3 M4 M5 M6 M7 M8 M9 M10 M14
Number:464
We make pan head tapping screws in white zinc plated carbon steel, self-tapping with a wide bearing face, a Phillips recess and a sharp point, quoted from M1 to M14. Thread, point, head diameter and sheet thickness come from your drawing, and the first article is driven into your own sheet.
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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 pan head tapping screw is a self-tapping screw with a domed head of low profile, a wide flat bearing face underneath and a Phillips recess on top. The thread cuts its own thread into a pilot hole and the sharp point starts it, so the screw is driven once and holds where it is put. This family is made in carbon steel with a white zinc plate, quoted from M1 to M14 with Number 464 and filed under the self-tapping group.
Pan head. A shallow dome with a flat annular bearing face. The face is wide compared with a cheese or binding head, and the dome keeps the edge from being sharp.
Self-tapping thread. A coarse thread with a sharp crest, sized to form its own thread in a pilot hole.
Sharp point. A tapered end that finds and enters the hole and starts the thread on the first turn.
White zinc plate. A trivalent zinc deposit, bright and thin, which protects the steel sacrificially and meets the common RoHS limits.
A pan head tapping screw holds on two surfaces: the thread in the hole and the bearing face under the head. The trade press writes about the thread, but on light assemblies the face is what decides whether the joint stays tight, because a pan head that does not sit flat on its face loses preload no matter how well the thread is formed.
The bearing face is an annulus, not the whole underside. Under the dome the face is flat from the edge of the head inward to a small radius where the head turns into the shank, and it is only that flat band that touches the panel. A panel that is domed, burred or punched without a chamfer touches the face on one side only, and the screw tilts as it is tightened.
The fillet between head and shank is the other part that matters. It is where the stress concentrates when the screw is driven past its seat, and it is where a pan head tapping screw most often snaps — the thread survives, the panel is undamaged, and the head comes off with the driver still in it. That failure is caused by the joint bottoming out and the driver continuing to turn.
Compared with a countersunk head, a pan head removes nothing from the panel. The clamp load passes through the full sheet thickness rather than through a cone cut into it, which is why a pan head is the better choice in thin or soft material. The cost is that the head stands above the surface, and anything sliding across the panel will find it.
The head diameter is what sets the bearing area, and on the same thread size a pan head is wider than a cheese head. Where the panel is soft, a washer face or a larger head spreads the same load over more material and stops the sheet from dimpling around the hole.
The recorded range is M1 to M14, covering M1, M2, M3, M4, M5, M6, M7, M8, M9, M10 and M14. Custom lengths up to 2,000 mm are subject to DFM review after drawing submission. For a pan head tapping screw the useful quotation is thread size, length, head diameter and point form, because those four decide the pilot hole and the bearing.
| Item | How it is defined | What we control |
|---|---|---|
| Head | Pan head, domed, flat face | Head diameter, height and face flatness |
| Recess | Phillips cross | Recess depth and size, driver fit |
| Thread | Self-tapping, coarse pitch | Pitch and major diameter, gauged |
| Point | Sharp, tapered | Point angle and thread start |
| Finish | White zinc | Deposit thickness and adhesion |
| Length | Under the head to the point | Measured on the shop plate |
Length is measured from under the head, so a pan head tapping screw is quoted as the length that passes through the panel plus the material it has to engage. On a thin sheet, most of the screw sticks out through the far side, and that protruding end is worth looking at on the drawing: it can catch a cable, or be closed on by a second panel.
Head diameter matters more than it looks in a table. A wide pan head on a small thread gives a large bearing area and a shallow dome, which suits a soft panel; a narrow one looks lighter and dimples the sheet sooner. Where the panel is a composite or a plastic, the face is what fails first.
Three features define this part: the pan head, the self-tapping thread and the Phillips recess. The first spreads the load, the second makes the thread, and the third limits the torque before the joint destroys itself.
| Feature | What it gives | What it costs |
|---|---|---|
| Wide flat face | Spread load, no dimpling | Head stands above the surface |
| Domed top | No sharp edge to catch | Nothing to grip if the recess fails |
| Self-tapping thread | Holds in thin sheet | Strips if over-driven |
| Sharp point | Starts without a fixture | Needs a pilot hole of the right size |
| White zinc | Sacrificial protection, RoHS compliant | Thin; rust starts at a scratch |
The pan head is the most forgiving of the common heads for a hand driver. The face is broad enough that a small burr does not tilt the screw much, the dome does not cut the driver hand, and the recess sits in the middle of a flat top that a bit finds easily. That forgiveness is why the form is everywhere in appliances and light enclosures.
The trade is the projection. A pan head sits proud of the panel by its full height, so it is the first thing to snag on a cover, a cable or a hand. Where the surface has to be clear, the flat head version of the same screw does the same job with the head buried.
The recorded finish is white zinc, the trivalent bright deposit used where a part has to look clean and meet RoHS limits. It is sacrificial: the zinc corrodes first and protects the steel beside it, so a scratch on the head or a bare patch at the crest is not the same emergency as it is on a barrier coating.
| Option | How it protects | Effect on thread and recess | Typical use |
|---|---|---|---|
| White zinc | Sacrificial zinc, trivalent | A few microns; fit re-checked | Indoor appliances and panels |
| Black zinc | Sacrificial zinc, dark | A few microns; fit re-checked | Dark equipment and trim |
| Nickel plated | Barrier deposit, bright | Thin; decorative | Visible indoor panels |
| Black oxide | Conversion film, oiled | No measurable build | Internal machine parts |
| Stainless, plain | Passive chromium oxide film | None; gauged as cut | Outdoor and damp joints |
On a self-tapping thread the plate enters the fit twice: it thickens the crest that has to enter the pilot hole, and it narrows the recess the bit has to fill. Zinc is thin enough that both are usually within the tolerance of the joint, but the first article is checked after plating rather than before, because that is the condition the customer receives.
The white zinc also sets a shelf life. A bright trivalent deposit without a topcoat can build white corrosion in a damp store, which looks like a defect and is not one. Where parts are stored for a long time before use, a thin passivation or a sealed bag is worth asking for.
Three assemblies where a pan head tapping screw is the fixing:
| Where it sits | The screw closes a casing or fixes a bracket where the panel is thin, the head has to be comfortable to drive and the part is assembled by hand in volume. |
| When it goes wrong | An over-driven screw strips the sheet, and a burr under the head tilts the screw and loosens the joint. |
| Why it happens | The panel is thin, the assembly is by hand, and the fixing is repeated. |
| What we control | Head face flatness and thread checked, pilot hole agreed against sheet thickness. |
| Where it sits | The screw fixes a cover, a DIN rail clip or a terminal block plate where a generous head spreads the load on a thin wall. |
| When it goes wrong | A stripped thread leaves a lid that will not close, and a zinc plate that rusts inside a humid box marks the terminals. |
| Why it happens | The wall is thin, the head is accessible, and the part sees damp. |
| What we control | Thread gauged per batch, plating and salt-spray checked. |
| Where it sits | The screw fixes a hinge plate or a bracket where the panel is chipboard or a thin steel plate and the head has to bear without crushing it. |
| When it goes wrong | A small head dimples the material, and the joint loses preload as the material settles. |
| Why it happens | The material is soft, the load is a bearing load, and the fixing is visible. |
| What we control | Head diameter and face flatness checked, first article fitted into the panel. |
Four reasons that matter on a self-tapping screw, each tied to what the drawing has to prove:
|
Face and pilot hole reviewed together
The bearing face, the sheet thickness and the pilot hole are reviewed as one set, because a pan head that dimples a soft panel is a joint problem before it is a screw problem. Basis: Face, hole and sheet reviewed together. |
Head, thread and plate in one route
The pan head and the Phillips recess are formed in the heading stroke, the self-tapping thread is rolled, the point is formed and the parts are zinc plated in the same route. Basis: One route from wire to plated screw. |
|
Face checked flat, thread driven
The bearing face is checked for flatness and the recess driven with the production bit, then the first article is driven into a sheet of the customer thickness and pulled. Basis: First article driven into a test sheet. |
First article fixes the setting
The first article fixes the wire heat, the point die and the plating; repeat orders are compared against that record. Basis: First article signed off before the batch is released. |
Shi Shi Tong forms these pan head tapping screws from carbon steel wire on single-die headers that form the pan head and the Phillips recess in one stroke, rolls the self-tapping thread, forms the sharp point and sends the parts to white zinc plating. The first part of every run is measured on the head, driven into a sheet of the customer’s thickness and checked in a thread gauge before the batch continues.
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The head die sets the pan face, and it wears where the dome meets the flat. A worn die leaves a face with a slight crown, which rocks on the panel and shows up as a joint that loosens under vibration while the thread still measures correctly. Face flatness is checked on the first article for that reason.
What decides whether pan head tapping screws pass is the bearing face, the thread, the point and the plate. The inspection agreement covers those, and the criteria come from the drawing.
Head face and thread on the projector |
Thread gauged per batch |
Hardness checked against the grade |
Salt-spray testing of the plate |
Every pan head tapping screw is checked for head diameter, head height and face flatness on the first article, then driven into a test sheet and pulled to the strip point. The thread is gauged per batch on major diameter and pitch, the point is checked for angle, and the recess is driven with the production bit.
The plate is checked for thickness and adhesion, and the salt-spray sample is run where the customer’s environment asks for it. On a bright zinc part the first sign of trouble is white corrosion between the threads, which is why plating records and storage conditions are kept with the batch.
Records carry the drawing revision and the batch number, so a complaint about a joint that loosens can be traced to the sheet, the hole or the lot.
Every shipment of pan head tapping screws is traceable to the wire it was made from and to the plating batch. The grade and heat number are recorded on the material certificate supplied with the parts, and the plating record is kept with the inspection file.
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 plating. 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 self-tapping part the first article is driven into the customer’s own sheet, because the joint is the function. Buyers visit during the process to review samples and to see how the heads and points are formed.
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8,678+
customers served
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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 plating 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 |
Both are domed with a flat bearing face. A pan head has a wider face and a shallower dome; a cheese head has a taller, flatter top. The pan head spreads load better on a thin panel.
Between the root and the crest of the thread, sized to the sheet thickness and material. It decides whether the thread holds or strips, so it belongs on the drawing.
Usually the head is not sitting flat — a burr, a domed panel or a worn die leaves the face rocking, and preload is lost under vibration even though the thread is fine.
A self-tapping thread is made for one insertion. It can be removed and re-driven a few times with care, but each cycle cuts a little more material from the hole.
For occasional exposure it is a reasonable start, since zinc protects sacrificially. For permanent damp or salt, the stainless version of the same form is the answer.
Thread size and length, point form, head diameter and height, recess type, the sheet material and thickness, and the pilot hole if it is already cut.
How a pan head tapping screw project runs from drawing to repeat delivery:
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1
Send the drawing and the sheet you are fixing
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→ |
2
Pilot hole and thread size agreed
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→ |
3
First article driven into a test sheet
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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 thread size and length, the point form, the head diameter and height, the recess type, and the material and thickness of the sheet.
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Thread size
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Length
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Point form
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Head diameter
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Sheet thickness
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Pilot hole
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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
