High-temperature manganese phosphating process

Abstract

The invention discloses a high-temperature manganese phosphating process which comprises the following steps that a, a workpiece is electrically de-oiled to obtain a A product.; b, the product A is washed with hot water to obtain a B product; c, the product B is washed with cold water to obtain a C product; d, the C product is washed with acid to obtain a D product; e, the D product is cleaned with cold water to obtain a E product; f, the E product is surface-adjusted by immersing the E product in the first surface conditioning liquid containing the saponifier surface conditioning agent to obtain a F product; g, the F product is surface-adjusted by immersing the F product in a second surface conditioning liquid containing a manganese phosphate surface conditioning agent to obtain a G product; h, the G product is phosphated to obtain a H product; i, the H product is washed with cold water to obtain a product I; j. the product I is washed with hot water to obtain a J product; k, and theproduct J is dried to obtain a finished product. The high-temperature manganese phosphating process has the advantages of short process time and small mechanical fit tolerance, and the phosphating workpiece can withstand high speed, heavy load and large impact.

Description

Technical field [0001] The invention belongs to the phosphating process field of hydraulic pumps and motors, and particularly relates to a high-temperature manganese series phosphating process. Background technique [0002] Hydraulic pumps and motors are the abbreviations for hydraulic pumps and hydraulic motors. Some parts of hydraulic pumps and motors are usually phosphated. Phosphating is a process in which the workpiece undergoes chemical and electrochemical reactions with the phosphating solution to form a phosphate chemical conversion film. The phosphate conversion film is called the phosphate film. High-temperature manganese phosphating film is one of many types of phosphating film. It has a good anti-friction and self-lubricating effect. It also has the advantages of low cost and simple operation. It is widely used in high-speed operation of automobiles, motorcycles, and ships. Parts. [0003] The traditional high-temperature manganese phosphating process includes degreas...

AI Technical Summary

Problems solved by technology

Therefore, the change in the amount of phenolphthalein indicator will also lead to inaccurate detection data of high temperature manganese phosphating solution

[0014] In addition, since the free acid Fa and the total acid Ta are detected by dropping the NaOH standard solution manually, it cannot be guaranteed that the dropped NaOH standard solution and the components of the high-temperature manganese phosphating solution react completely according to the stoichiometric relationship of the reaction formula. , resulting in inaccurate detection data of high temperature manganese phosphating solution

[0015] In addition, the inhomogeneity of sampling the high-temperature manganese-based phosphating solution may also lead to inaccurate detection data of the high-temperature manganese-based phosphating solution

[0016] Therefore, manual titration detection of high-temperature manganese-based phosphating solutions has the defects that the detection data may be inaccurate, the detection repeatability is poor, and the detection reproducibility is poor, which will make it difficult to strictly control the free acid and total acid in the high-temperature manganese-based phosphating solution, making the workpiece The enlarged size after phosphating is difficult to control, and the phosphating dimensional tolerance of the workpiece is about 0.02mm out of tolerance, which makes it difficult to control the dimensional tolerance of the phosphating workpiece, especially for the 38CMoAlA workpiece after nitriding, the dimensional tolerance is particularly difficult to control, Therefore, the traditional high-temperature manganese phosphating process cannot be used for the phosphating of precision-sized workpieces, and is not suitable for workpieces with small mechanical fit tolerances.

[0017] Therefore, the traditional high-temperature manganese-based phosphating process has the defects of long process flow and inapplicability to workpieces with small mechanical fit tolerances, and the phosphating workpieces are difficult to withstand high speed, heavy load and large impact

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