The surface treatment of self-drilling screws requires specific procedures. What manufacturing processes are generally used for surface treatment? Hebei Wotu Fastener Manufacturing Co., Ltd. will explain oxidation treatment below.
The surface treatment of self-drilling screws requires specific procedures. What manufacturing processes are generally used for surface treatment? Hebei Wotu Fastener Manufacturing Co., Ltd. will explain oxidation treatment below.
Black coating with oil is a popular plating for industrial fasteners because it is the cheapest and looks good until the oil runs out. Since black coating has almost no rust-preventing ability, it will rust quickly after the oil is removed. Even in an oiled state, its neutral salt spray test result is only 3-5 hours. At the same time, blackened self-drilling screw fasteners have poor torque-preload consistency. To improve this, grease can be applied to the internal threads before screwing them in during assembly. Hebei Wotu Fastener Manufacturing Co., Ltd. (formerly Handan Pingyuan High Strength Fastener Manufacturing Co., Ltd.), a manufacturer of self-drilling screws, was founded in the 1990s and is one of the largest high-strength fastener manufacturers in North China.
DIN 931-style half-thread and DIN 933-style full-thread hex bolts should not be selected from diameter and overall length alone. The practical choice depends on the joint stack, required grip, location of the thread transition, available nut engagement, mating hardware, material or property requirement, coating system and governing product specification. A half-thread bolt is not automatically […]
A bolt manufacturer should be evaluated against a defined joint, drawing and acceptance plan—not a product list or unit price alone. Buyers need to verify whether the supplier can manufacture the required geometry, control material and heat-treatment requirements where applicable, manage threads and coatings as one dimensional system, inspect critical characteristics, preserve batch traceability and […]
