一、鋼絲繩使用注意事項
(一)使用前檢查內(nèi)容
鋼絲繩的磨損、銹蝕、拉伸、彎曲、變形、疲勞、斷絲、鋼絲繩繩芯露出的程度。
(二)保養(yǎng)注意事項
1. 鋼絲繩的使用期限與使用方法有很大關(guān)系,因此應(yīng)做到按規(guī)定使用,禁止拖拉、拋擲,使用中不準(zhǔn)超負(fù)荷,不準(zhǔn)使鋼絲繩發(fā)生銳角折曲,不準(zhǔn)急劇改變升降速度,避免沖擊載荷。
2. 鋼絲繩有鐵銹和灰垢時,用鋼絲刷刷去并涂油。
3. 鋼絲繩每使用4個月涂油一次,涂油時最好用熱油(50℃左右)浸透繩芯,再擦去多余的油脂。
4. 鋼絲繩盤好后應(yīng)放在清潔干燥的地方,不得重疊堆置,防止扭傷。
5. 鋼絲繩端部用鋼絲扎緊或用熔點低的合金焊牢,也可用鐵箍箍緊,以免繩頭松散。
6. 使用中,鋼絲繩表面如有油滴擠出,表示鋼絲繩已承受相當(dāng)大的力量,這時應(yīng)停止增加負(fù)荷,并進(jìn)行檢查,必要時更換新鋼絲繩。
7. 在使用過程中,應(yīng)注意防止以下情況出現(xiàn):
(1)鋼絲繩與電焊線接觸。
(2)鋼絲繩間直接接觸。
(3)鋼絲繩與金屬尖銳棱角經(jīng)常摩擦。
(4)鋼絲繩從已經(jīng)破損的滑輪上穿過。
(5)吊裝角度超過60o。
(6)在高溫物件上使用的鋼絲繩,必須采取隔熱措施,以防降低強度和壽命。
(7)鋼絲繩報廢切斷時,應(yīng)有防止繩股散開的措施。
二、鋼絲繩報廢標(biāo)準(zhǔn)
鋼絲繩出現(xiàn)下列情況之一,應(yīng)予以報廢:
1. 對于交繞的鋼絲繩在一個捻距(指任意一個鋼絲繩股環(huán)繞一周的軸向距離)內(nèi)的斷絲數(shù)達(dá)該繩總絲數(shù)的10%。
2. 吊運熾熱金屬或危險品的鋼絲繩,其報廢斷絲數(shù)取一般起重機的一半,如斷絲現(xiàn)象集中發(fā)生于局部,或在六倍于鋼絲繩直徑長度內(nèi)斷絲集中發(fā)生在一股上,應(yīng)按第1項中所規(guī)定的一半即可報廢。
3. 鋼絲繩表面層鋼絲腐蝕或磨損達(dá)表面原絲徑的40%。
4. 鋼絲繩有明顯的內(nèi)部腐蝕。
5. 鋼絲繩直徑減少量達(dá)7%。
6. 鋼絲繩與鋁合金接頭部位有裂紋或滑移變形;插編鋼絲繩索具插編部位有嚴(yán)重抽脫;澆鑄鋼絲繩錨具與鋼絲繩連接處有位移,發(fā)生抽脫現(xiàn)象。
7. 鋼絲繩表面有磨損或腐蝕,又有一定數(shù)量的斷絲,斷絲數(shù)應(yīng)在第1項或第2項的規(guī)定上乘以折減系數(shù)后判定:當(dāng)磨損或腐蝕率分別在10%、15%、20%、30%-40%時,折減系數(shù)對應(yīng)85%、75%、70%、60%、50%。
8. 整股斷裂或燒壞。
9. 局部外層鋼絲繩伸長呈“籠”形或鋼絲繩纖維芯的直徑增大較嚴(yán)重。
10. 鋼絲繩發(fā)生扭結(jié)、死角、硬彎、塑性變形、麻芯脫出等嚴(yán)重變形。
1. Matters needing attention in the use of wire rope
(1) Check the content before use
The degree of wear, corrosion, stretching, bending, deformation, fatigue, broken wire, and exposure of the core of the wire rope.
(2) Maintenance precautions
1. The service life of the wire rope has a lot to do with the method of use. Therefore, it should be used according to the regulations, dragging and throwing are prohibited, overloading is not allowed during use, the wire rope is not allowed to bend at an acute angle, and the lifting speed is not allowed to change sharply. Avoid shock loads.
2. When the wire rope has rust and dust, use a wire brush to remove it and apply oil.
3. The steel wire rope should be oiled every 4 months. It is best to soak the rope core with hot oil (about 50℃) and wipe off the excess grease.
4. After the wire rope is wound, it should be placed in a clean and dry place, and should not be stacked to prevent sprain.
5. The end of the wire rope should be fastened with steel wire or welded with alloy with low melting point, or can be fastened with iron hoops to avoid loosening of the rope head.
6. ??During use, if oil droplets are squeezed out on the surface of the wire rope, it means that the wire rope has been subjected to considerable strength. At this time, the load should be stopped and the inspection should be carried out. If necessary, replace with a new wire rope.
7. During use, care should be taken to prevent the following situations from appearing:
(1) The wire rope is in contact with the welding wire.
(2) Direct contact between steel wire ropes.
(3) Steel wire rope and metal sharp edges and corners are often rubbed.
(4) The wire rope is passed through the broken pulley.
(5) The hoisting angle exceeds 60o.
(6) The steel wire rope used on high temperature objects must be insulated to prevent the strength and lifespan from being reduced.
(7) When the wire rope is scrapped and cut, there should be measures to prevent the strands from spreading.
2. Steel wire rope scrap standard
The wire rope should be scrapped if one of the following occurs:
1. The number of broken wires in a lay length (referring to the axial distance of any wire rope strand around a circle) for the entangled wire rope reaches 10% of the total wire number of the rope.
2. For steel wire ropes that are used for lifting hot metal or dangerous goods, the number of scrapped and broken wires is half of that of ordinary cranes. If wire breakage occurs locally, or within six times the diameter of the wire rope, it should be Half of the stipulated in item 1 can be scrapped.
3. The corrosion or abrasion of the steel wire on the surface of the wire rope reaches 40% of the original wire diameter.
4. The steel wire rope has obvious internal corrosion.
5. The wire rope diameter is reduced by 7%.
6. ??There are cracks or slipping deformation at the joint between the steel wire rope and the aluminum alloy; the insertion part of the inserted braided steel wire rope is severely pulled off; the cast wire rope anchorage and the wire rope have displacement at the connection point, and the phenomenon of pulling off occurs.
7. The surface of the steel wire rope is worn or corroded, and there are a certain number of broken wires. The number of broken wires should be determined by multiplying the provisions of item 1 or item 2 by the reduction factor: when the wear or corrosion rate is 10%, 15 %, 20%, 30%-40%, the reduction factor corresponds to 85%, 75%, 70%, 60%, 50%.
8. The whole strand is broken or burned out.
9. The local outer steel wire rope elongates in a "cage" shape or the diameter of the steel wire rope fiber core increases severely.
10. The wire rope is seriously deformed such as kinks, dead ends, hard bends, plastic deformation, and hemp core out.