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:Iron screw
Materials:Carbon Steel
Surface treatment:Eco Black Zinc Plated, Eco White Zinc Plated
Size:5/16"-18*72
We manufacture carbon steel flat head slotted-drive screws in 5/16″-18*72, cold headed, thread rolled with eco black zinc plating applied after rolling, and inspected against the drawing, for sheet-metal covers, machined plates and conveyor guards, with the head and the thread formed on the same blank and every batch gauged before packing. Head diameter, recess depth, thread length and surface finish are made to your drawing, and the driver bit match is reviewed before production.
Shi Shi Tong supplies carbon steel flat head screws with a Slotted drive on a made-to-order basis. For this item the recorded configuration is Eco Black Zinc Plated finish, , a machine thread, right hand direction and metric measurement. Any requirement outside the recorded configuration is reviewed against the drawing before the batch runs.
The table below is the specification recorded for this screw, not a catalogue of every size the factory can produce. Where a project needs a different head, drive, thread or finish, the part is reviewed as a drawing-based item.
Carbon steel is chosen where the strength and the cost of the part matter more than corrosion resistance. Because the base metal will rust once the surface is broken, the finish becomes part of the specification rather than an optional extra.
A flat or countersunk head is conical underneath and sits flush with the joint surface once the matching countersink is cut. It leaves a smooth face after assembly and centres the screw in the hole.
A slotted drive is a single straight slot, driven with a flat blade. It is simple to inspect and easy to clean out, and it allows the slot to be aligned with a reference feature on the part.
The recess or drive size is matched to the tool used on your line. State the driver size or the torque target on the drawing so the head and the drive are reviewed together with the head diameter.
A machine thread engages a pre-tapped hole or a nut rather than cutting its own path into the material. The mating thread has to be prepared to the same size and class, so the screw and the tapped hole are specified together.
Zinc plating puts a sacrificial zinc layer over the steel. Where the coating is scratched the zinc corrodes first and the base metal stays intact.
Packing is recorded as plastic bag + carton. Parts are bagged before they go into the carton so the thread and the head are protected in transit.
The joints below are where these screws actually fail when the geometry is loose, so each paragraph names the failure, what it costs and the dimension we hold:
Sheet-metal enclosures and covers. On countersunk screws closing panels that must sit flush with the surface, the head stands proud or sinks below the sheet, so the panel does not sit flat. The cover is reworked or replaced and the paint line is repeated, because head angle and head diameter are not matched to the countersink in the sheet. We control it at the source: the head angle, the head diameter and the head height are cut as one set and checked with a countersink gauge.
Machined plates and base frames. On screws fixing plates where the head must not stand above the machined face, the screw bottoms in the countersink and the plate is lifted off its seat. The assembly is stripped and the plate re-machined, because the shank-to-head transition is too long for the thickness of the plate. We control it at the source: the transition length and the head height are set so the head sits inside the countersink at the drawing depth.
Conveyor guards and machine covers. On fixings on guards that are removed for cleaning and maintenance, the recess wears and the driver slips, scratching the powder-coated surface. The guard is repainted and the line is stopped for the touch-up, because drive depth is shallow and the driver rocks in the recess when used off-axis. We control it at the source: drive depth and drive width are held so the bit seats fully before torque is applied.
The size field recorded for this item is 5/16″-18*72. Sizes inside that range are quoted against the drawing, because the head diameter, the head height and the length are set per part rather than taken from one stock list.
Where a length or a diameter outside the recorded range is needed, the part is treated as a drawing-based item and the tooling is reviewed before quoting.
Wire and bar are bought against the mill certificate: grade, heat number and standard are checked before forming, and the material report is kept with the production record.
Manufacturing since 1998. Parts are produced to your drawing or sample; overall range M0.8-M16 diameter and 0.4-2000 mm length, each subject to material, structure and process review.
A complete production process holds the dimensional tolerances and the appearance of the part; the inspection scope is agreed with the drawing.
Plain and coated finishes are specified per joint so the head and the thread survive repeated driving; where a locking feature is required it is defined on the drawing rather than added at random.
The route is planned from the approved drawing rather than taken from a stock list:
Inspection follows the features that decide whether the screw assembles: the head, the drive, the thread and the surface.
Results are recorded per batch so a repeat order can be compared with the first delivery.
ISO 9001:2015 Quality Management System Certification and an SGS testing report are the two documents stated for this product. Material reports for the raw wire are available with the shipment.
 |
 |
 |
Fasteners are bought by people who have to make a line run again next quarter, so the order history is part of the specification.
|
8,678+
Customers served
|
87%
Repeat orders
|
56%
Referral orders
|
89
Countries and regions
|
Other screws produced to drawing at the same plant:
The material recorded for this item is Carbon Steel. The grade is confirmed against the material report kept with the batch.
The recorded surface treatment is Eco Black Zinc Plated. Where a project specifies a different finish, the finish is agreed on the drawing before the batch runs.
The size field recorded for this item is 5/16″-18*72. Head diameter, head height and length are set per part against the drawing rather than taken from one stock list.
Yes. A part outside the recorded configuration is treated as a drawing-based item: the head, the drive, the thread and the finish are reviewed together before quoting.
Send the drawing with the head, the drive, the thread and the finish you need. The reply covers the feasible route, the inspection scope and the lead time for the batch.
+86 13143444311
sst@szsst88.com
