Cold heading Service

ASME B18.6.3 Torx Flat Head Self Tapping Screw

ASME B18.6.3 Torx Flat Head Self Tapping Screws are designed for fastening applications where a flush surface and reliable tool engagement are important. The six-lobe drive transfers turning force through multiple contact points, while the flat countersunk head allows the screw to sit level with the surrounding surface when installed in a properly prepared hole. The thread design enables the screw to form mating threads during installation in suitable materials, making it useful for sheet metal work and equipment assembly.

Our production process covers material selection, forming, thread production, heat treatment, and final inspection. As an ISO 9001-certified company, we work with production facilities equipped with cold heading and thread rolling machines to meet specified head dimensions and thread requirements. We verify material grades against order specifications, monitor hardness after heat treatment, and inspect critical dimensions, drive recesses, and surface finishes before shipment. This process helps us maintain consistency across production batches and meet the technical requirements of different orders.

ASME B18.6.3 Torx Flat Head Self Tapping Screw Stainless Steel

ASME B18.6.3 Torx Flat Head Self Tapping Screw

Specification:

Item	Specification
Standard	ASME B18.6.3
Product Type	Torx Flat Head Self Tapping Screw
Thread Diameter	#1-5/16"
Point Type	Type AB Pointed Tip
Material	Carbon Steel, Stainless Steel
Steel Property	SAE J933
Stainless Steel Property	ISO 3506-4
Surface Treatment	Black Oxidation,Zinc Plated,Bright Finish
Inspection	Dimensions,Thread,Hardness,Coating

Dimension Chart:

Drawing of ASME B18.6.3 Torx Flat Head Self Tapping Screw

Mon	#1	#2	#3	#4	#5	#6	#7	#8	#10	#12	1/4	5/16
P	42	32	28	24	20	20	19	18	16	14	14	12
dk max	0.137	0.162	0.187	0.212	0.237	0.262	0.287	0.312	0.362	0.412	0.477	0.597
dk min	0.12	0.144	0.167	0.191	0.215	0.238	0.262	0.285	0.333	0.38	0.442	0.556
k	0.043	0.051	0.059	0.067	0.075	0.083	0.091	0.1	0.116	0.132	0.153	0.191
e	0.058	0.069	0.094	0.094	0.111	0.111	0.132	0.132	0.155	0.178	0.2	0.266
No.	T5	T6	T8	T8	T10	T10	T15	T15	T20	T25	T27	T40
t max	0.017	0.022	0.025	0.033	0.045	0.045	0.045	0.051	0.065	0.07	0.09	0.105
t min	0.012	0.017	0.02	0.028	0.035	0.035	0.035	0.04	0.05	0.055	0.075	0.087
d max	0.075	0.088	0.101	0.114	0.13	0.139	0.154	0.166	0.189	0.215	0.246	0.315
d min	0.069	0.082	0.095	0.108	0.123	0.132	0.147	0.159	0.182	0.208	0.237	0.306
d1 max	0.049	0.064	0.075	0.086	0.094	0.104	0.115	0.122	0.141	0.164	0.192	0.244
d1 min	0.046	0.06	0.071	0.082	0.09	0.099	0.109	0.116	0.135	0.157	0.185	0.236

Mechanical Property:

The mechanical properties of ASME B18.6.3 Torx Flat Head Self Tapping Screws influence their performance during thread formation and installation. Torsional strength is important when driving the screw into the workpiece, while hardness and head integrity affect its ability to withstand installation forces.

SAE J933 – Carbon Steel Self-Tapping Screws

For carbon steel Torx flat head self-tapping screws, hardness and torsional strength are important for preventing breakage during installation. Appropriate material selection and heat treatment help the screw withstand driving torque while maintaining the integrity of the flat head and Torx recess. The applicable SAE J933 requirements should be used to verify mechanical performance.

ISO 3506-4 – Stainless Steel Self-Tapping Screws

Stainless steel Torx flat head self-tapping screws must balance installation performance with corrosion resistance. Their mechanical properties depend on the stainless steel grade, and torsional performance is particularly relevant when the thread-forming section encounters resistance during installation. Compliance with the applicable ISO 3506-4 requirements helps establish suitability for the intended fastening application.

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