Production of conveyor belts
Patent Information
- Application Number
- DEH0147828
- Authority / Receiving Office
- DE · DE
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 1936-06-07
- Publication Date
- 1939-11-03
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
Existing conveyor belts made from low-alloy steels require careful control of annealing times and temperatures to achieve desired strength properties, leading to potential cracking and operational hazards during crack propagation, and the manufacturing process is complex.
Using an alloyed carbon steel with increased carbon content (0.40% to 0.50%) and additional elements like Cu, the conveyor belts are produced through hot pre-rolling, intermediate annealing at 650°C, and final annealing between 500-600°C, reducing the need for precise annealing control and enhancing strength and elongation properties.
The solution results in conveyor belts with improved strength (100 kg/sqmm) and elongation (up to 12%), minimizing crack propagation to small, controlled tears, reducing operational risks, and simplifying repair and riveting processes.
Description
[0001] Manufacture of conveyor belts Patent 676 26o relates to the use of unalloyed carbon steel with 0.35 to 0.4 °% C, 0.55 - 0.75 ° / o Mn, 0.20 - 0.30 ° / o Si, 0.015 - 0.030' / , P, 0.025 - 0.040 ° / o S, Residual iron which, as usual, is pre-rolled, then cold-rolled into strips at about 650°C with the inclusion of one or more intermediate annealing processes. and then annealed at a temperature not exceeding 550°C for the manufacture of conveyor belts.
[0002] According to the invention, an alloyed carbon steel is also to be used for the manufacture of conveyor belts, which over 0.40 ° / o up to 0.50 °% C, 0.55 to 0.75: ° / o Mn, 0.20 - 0.35 ° / o Si, O,OIS - 0.035 ° / o P, 0.025 - 0.040 ° / o S, approximately 0.15 ° / o Cu, Rest Iron This steel is, as usual, hot pre-rolled, then cold-finished at approximately 650°C with one or more intermediate annealing processes. The steel is rolled into strips and then annealed at a temperature between 500 and 600°C. A steel with a viscosity of over 0.40 to 600°C is particularly suitable for this purpose. Contains 0.45% carbon.
[0003] The final annealing process ensures that, on the one hand, the increase in strength caused by cold rolling is only slightly reduced, While, on the other hand, the elongation increases considerably. Steel conveyor belts with a tensile strength of gkg / mm² are obtained using this method. and whose elongation is up to 1a° / , . Therefore, it is not necessary to quench the strips from a high temperature before final annealing. to harden like the low-alloy chromium-nickel steel conveyor belts.
[0004] Furthermore, the conveyor belts according to the invention also behave more favorably than alloy belts when cracks occur. While a belt According to the invention, after an initial tear, the known alloyed bands tend to tear slowly and in a narrow area. A small crack can spread in a glassy fashion. This can happen when an alloy band breaks. Individual pieces can fly off like explosives and endanger the operating crew. However, if cracks appear in the conveyor belt according to the invention... If you do this, it is easily possible to cut out the damaged areas right at the beginning and then cut the tape with a reduced width without... to allow operational disruptions to continue. Riveting is also simpler, whereas with tempered strips it is more difficult due to the slightly higher resin content. Care must be taken due to the risk of cracking.
[0005] The present invention represents an improvement over the subject matter of the main patent insofar as the increase in the Carbon content simplifies operations in the manufacture of conveyor belts compared to the use of steels with less than 0.40 0 / 0 Carbon is produced. The annealing times and temperatures need to be less carefully controlled to achieve the required strength properties. to achieve. Furthermore, these strength properties can be produced within much narrower limits. It is therefore a significantly greater Uniformity of the conveyor belts is ensured.
Claims
[0006] PATENT CLAIM: The use of unalloyed K-lens steel with over 0.40% up to 0.50 o / o C. 055 to 0.75% Mn, 0.20 - 0.35% Si, 0.015 - 0.03590 P, 0.025 - 0.0400 / 0 S, approximately 0.15 0 / 0 Cu, Residual iron The material is, as is customary, pre-rolled hot, then cold-rolled into strips at about 650°C with the inclusion of one or more intermediate annealing processes. rolled out and then annealed at a temperature between 500 and 600°C, for the manufacture of conveyor belts (supplement to the patent) 67626o).