Proof chain wire rope hoist manufacturers that bear load carrying , but also both explosion-proof performance , and therefore must be careful to 1.5 ton Electric Chain Hoists distinguish the procurement generally be identified from the following aspects : First, the external aspects : 1 ) , proof chain 15 ton electric chain hoist and load chain, hooks and other parts in the national standard bearer timing is safe load conditions occur deformation and cracks ; 2 ) , explosion-proof chain to pull down the chain is smooth , non- jammed chain sprocket ; 3 ) , bearing chain lifting process, is running smoothly , there can not be reduced up to be comfortable lifting heavy lifting when 1.5 ton electric chain hoists strictly prohibited ; 4 ) , the hook should be provided at the slip, anti-off devices. 5 ) , and down -proof hook flapper chain hoists , explosion-proof products if there is a serious distortion caused by ineffective is not guaranteed to be no slip hook hanging objects . Second, the internal aspects: 1 ) , proof chain hoists and various internal gear shaft due to quenching is not in place , resulting in broken teeth can not normally rise or fall . 2 ) , the material shall be copper alloy.