Wrench selection principles:
HOAMR gives priority to socket wrenches and socket wrenches, followed by open-end wrenches and adjustable wrenches.
What material is good for a wrench? The wrench material is generally carbon steel and alloy steel. Alloy steel is generally chromium vanadium steel. There are many grades of vanadium steel. Generally speaking, the higher the grade, the better the quality. Carbon steel is generally used for low-end products, and chromium vanadium steel is generally used for high-end products.
Appearance style:
There are many styles of dual-purpose wrenches. Generally, there are three types: convex shank, concave shank, and flat shank. The production process of each product is different, and the surface treatment is also very different. The convex tibia is mostly made of carbon steel, and the concave tibia is mostly made of alloy steel.
Appearance punching:
The plum blossom has a full shape, graceful curves, uniform wall thickness, and is more standard. In the punishment part, the glycoside is round and the outside is too soft and smooth. The inner wall of the hole is smooth and uniform, without burrs or knife marks. Handshake, round shape, no flash.
Surface treatment:
There are many kinds of surface treatments, such as polishing, mirror, frosted fog, blackening, electrophoresis, etc. There are many subtle differences in frosted fog, among which watermark fog is the most high-end. Another very important thing is the quality of the above specifications and trademarks. Logos and instructions should be clear and legible, and the fonts should be even and refined.
thickness:
The smaller the thickness of a wrench of the same specification, the higher the requirements for torque and other standards. The lighter the weight, the more comfortable it is for people to use, so the quality is similar.
Tolerance range:
For example, a 14MM nut corresponds to a 14MM opening; the penalty needs to be appropriately enlarged to facilitate quick cooperation; but it should not be enlarged too much, as it will damage the nut and make it "slip". So you need to use the opening or five points exactly.
Torsion and hardness: Excellent quality requires a perfect combination of hardness and toughness. If it is too hard and tough, it will not break easily; if it is too soft, it will be easy to form.