Description

The brick making machine is an indispensable and important equipment in the brick and tile industry, and the spiral reamer is the key component of the brick making machine. Its life and quality play a decisive role in the use of the brick making machine. However, due to its harsh working conditions, the spiral reamer has become a vulnerable part, so how to improve its quality and prolong its service life is an important issue.

1. Welding method

Common surfacing welding methods for brick machine spirals include manual arc welding, carbon dioxide gas shielded welding, and spray welding. Comprehensive consideration of welding speed, deposition rate, production cost and other factors, should choose carbon dioxide gas shielded welding, that is, the gas shielded welding method for spiral surfacing. The main welding equipment for gas shielded welding is a gas shielded welding machine, and the 500 type is generally used.

2. Selection of surfacing materials

Reasonable selection of surfacing material is an important link before spiral surfacing repair. The selection of spiral surfacing welding materials for brick making machines generally has the following principles:

1. Meet the working conditions of the spiral reamer

The service conditions of the spiral reamer after surfacing repair are the most important basis for selecting wear-resistant materials for surfacing. Since the spiral reamer works under the condition of low-stress abrasive wear, the surfacing material must have high hardness and high wear resistance, but the requirements for its impact toughness are not high.

2. Select wear-resistant surfacing materials from an economic point of view

When there are several wear-resistant surfacing materials that can meet the requirements of use, the surfacing materials with low price should be selected as far as possible to reduce the cost of surfacing parts. However, it should be noted that the high-alloy surfacing materials that may be more expensive have a longer service life. At this time, their economical efficiency should be compared comprehensively to choose surfacing materials that meet the requirements of use and have good economical efficiency.

3. The operational performance of surfacing materials should be considered

Under the premise of satisfying the spiral use conditions and economic indicators, we should try our best to choose surfacing welding materials with simple process and easy operation.

4. Recommended surfacing materials

Wear-resistant welding wire, composite welding wire filled with tungsten carbide particles, surfacing single layer, hardness up to 68 HRC. The most wear-resistant welding wire in the whole network, the wear resistance is three times that of ultra-high chromium cast iron. It is especially suitable for the spiral wear condition of the brick machine.

3. Preparation before welding

Clean the surface of the spiral reamer, especially the thorough rust removal. Interlayer cleaning should also be thorough to prevent welding defects such as slag inclusions. Check to make sure that the purity of the CO2 shielding gas is >99.8% and should not be <99.5% minimum.

4. Recommended welding parameters

Wear-resistant welding wire diameter 1.6mm, welding current 220~280A, welding voltage 22~28V. The shielding gas is pure carbon dioxide or pure argon, the amount of shielding gas is 20L/min, the extension length of the welding wire is 15~20mm, the welding speed is 35cm/min, the inclination angle of the welding torch is 80 degrees, and the current type is direct reverse flow.

5. Surfacing process of spiral reamer

1. One layer of surfacing welding in area A on the front of the reamer, with a thickness of 3mm. 2 layers of surfacing welding in area B, with a total thickness of 5mm.

2. There are 3 layers of overlay welding on the side of the reamer, with a total thickness of 8mm. Before welding the sides, cut the front of the reamer a centimeter along the outer edge.

3. The distance between the front end of the welding torch and the workpiece is 15~20mm.

4. The angle between the welding torch and the horizontal ground is 60~70 degrees.

5. During the welding process, the welding torch swings evenly from side to side, with a swing width of 30mm.