The boom of the crane should be a compound lever.
Cranes are inseparable from steel wire ropes. The main varieties of domestic steel wire ropes are as follows:
1. Phosphating coated steel wire rope (Chinese patent). The steel wire is treated with manganese and zinc-manganese phosphating. The wear resistance and corrosion resistance of the steel wire have been comprehensively improved. It is not easy to wear and rust, making the fatigue life of the phosphate-coated steel wire rope 3 times that of the smooth steel wire rope of the same structure (under comparable conditions in the laboratory), surpassing imported steel wire ropes and phosphate-coated steel wire ropes. It is fully replacing all types of smooth steel wire ropes, and can also be used as a replacement for galvanized steel wire ropes that are first plated and then pulled out with a thin zinc layer (the corrosion resistance can be tested through a salt spray test). Because of its extremely long service life, the average daily use cost is only that of smooth steel wire ropes. 40-55%, better quality stability and reliability.
2. Galvanized steel wire rope, including hot-dip galvanizing and electro-galvanizing. The thicker the galvanized zinc layer, the stronger the corrosion resistance. The thickness of the zinc layer is expressed in grams/square meter.
3. Stainless steel wire rope, mainly 304 or 316 stainless steel, which has excellent anti-corrosion effect but is expensive
4. Plastic-coated steel wire rope, based on carbon steel wire rope, with an outer layer Coated with polyethylene, polypropylene or nylon
5. Smooth steel wire ropes have a short service life and a sharp drop in market demand, and are being completely eliminated by phosphate-coated steel wire ropes.
For lifting machinery used in atmospheric environments, manganese-based phosphating-coated steel wire ropes are preferred, in heavily corrosive environments, hot-dip galvanized-phosphating double-coated steel wire ropes are preferred, and offshore steel wire ropes are preferred in seawater. When purchasing, please note that the name of the steel wire rope must be indicated on the purchase invoice, such as phosphate-coated steel wire rope or 316 stainless steel wire rope, to prevent unscrupulous companies from infringing on their legitimate rights and interests with counterfeit products. In addition, patented products generally have patents on the outer packaging of the steel wire rope. No. spray marking, the warranty document should have main technical indicators, such as the type of phosphate coating and film weight (the weight, wear resistance, corrosion resistance, etc. of the phosphating film have an important impact on the service life of the steel wire rope), which are for reference only.