Annual inspection items and requirements of hoist cranes - News & Trends - Chinese Crane Manufacturers, Factories & Products

The annual inspection of the hoist crane is a periodic inspection and maintenance performed by professional maintenance personnel or crane maintenance workers on an annual basis. On the basis of daily and monthly inspection and maintenance, according to the number and severity of the hoist crane failure, it can be determined by itself. The annual inspection cycle is one or two years. The requirements for some items of the annual inspection are the same as that of the monthly inspection . The annual inspection is different from the daily or monthly inspection mainly in that the annual inspection does not require visual inspection or observation. The year is a comprehensive inspection and test run. The main parts shall be disassembled and inspected, and the parts with serious wear and deformation shall be subjected to specific size inspections. For the use limit (scrap standard) or the expected date of the next annual inspection The parts that may reach the extreme danger of wear and scrap must be replaced or repaired in time, and necessary maintenance should be done at the same time.

The specific inspection items, maintenance standards and recording methods of the annual inspection are detailed in the contents and requirements listed in the following table.

Annual inspection items and requirements for hoist cranes

Check item				Overhaul standard
Running track	Crane track status	1	Clean state of track tread	Don’t collect dust, iron filings, and don’t stick to oil and sewage
		2	Track tread detection	Supporting track: S≤10m; △S=±8mm S＞10m; △S=±[3+0.1(S-10)]mm Suspension type track: △S=±5mm Note: S-span, △S- Span tolerance
		3	Orbital inclination	≤1/1000
		4	Elevation difference between two tracks of the same section	≤S/1000
		5	Elevation difference of track support points on the same side	≤I/1000 (I- spacing between supporting points)
		6	Seam spacing of rolling track	Seam spacing≤2mm
		7	Track seam misalignment	Up and down, left and right phase cones on the tread ≤ 1mm
		8	Track crack and deformation inspection	The track must not have cracks and deformation (plasticity)
		9	Fatigue strength of track tread	The track tread shall not have peeling fatigue damage
		10	Track wear	Support-shaped track: wear ≤ 10% of the original size; suspended track; tread ≤ 10%; width ≤ 5%
		11	Track fixed installation inspection	The bolts must not be loose; the welds must not have cracks
Crane bridge	Main beam	12	Main beam appearance quality inspection	No trauma or abnormal deformation; the amount of rust ≤ 10% of the thickness of the original plate; no peeling of the paint
		13	Weld quality inspection	There must be no cracks in the weld
		14	Inspection of the upper camber of the main beam in the middle of the span	The degree of camber △F=(1/1000~1.3/1000)S
		15	Main beam side bend inspection	Side bend value△Fp≤S/2000
		16	Inspection of the wear condition of the running track of the main beam hoist	For the main beam I-beam track, the tread wear is less than 10% of the original size; the width wear is less than 5% of the original size; for the gourd double beam and other light, heavy rails, and square steel rails, the tread and side wear are less than the original size 10%
		17	Local bending deformation of main beam I-beam rail flange	The load-bearing flange of the I-beam main beam shall not have obvious collapse deformation (plastic deformation)
		18	Double girder gauge inspection	Gauge deviation at the end of the span: ±2mm; Gauge deviation at the middle of the span: +6mm
		19	Fixed installation inspection of horizontal supporting rail	When using bolt connection, the fixed connection bolts must not be loose; when using welding fixed connection, there must be no cracks in the welding seam
	End beam	20	End beam appearance quality inspection	No trauma or abnormal deformation; the amount of rust ≤ 10% of the thickness of the raw material; no peeling of the paint
		twenty one	Weld quality inspection	There must be no cracks in the weld
		twenty two	Track deviation	K≤3m; △K=±3mm K＞3m; △K=±K/1000 (K-track, △K-track deviation)
	Crane operating mechanism	twenty three	Run motor abnormality check	The motor shall not be lifted reluctantly, noisy or have abnormal sound
		twenty four	Run brake check	The brake should be safe, reliable and sensitive; the brake parts should be scrapped and replaced when the following conditions occur : cracks; brake ring or brake pads and other linings wear up to 50% of the original thickness; spring plastic deformation; small shaft or shaft hole diameter wear When it reaches 5% of the original diameter. The brake friction surface of the brake wheel should not have defects that hinder the braking performance or be contaminated with oil. When the thickness of the rim of the brake wheel is worn to 50% of the original size, and the wheel surface is uneven to 1.5mm, it should be scrapped.
		25	Running reducer installation status	The fixing connecting bolts must not be loose
		26	Run a visual inspection of the reducer	The shell must not be damaged or worn
		27	Run transmission gear quality check	The inspection gear should be scrapped when there is no one of the following conditions; the gear has cracks; the gear has broken teeth; the pitting wear of the tooth surface reaches 30% of the meshing surface, and the depth reaches 10% of the original tooth thickness; the first-stage meshing gear tooth thickness The wear reaches 15% of the original tooth thickness, the tooth thickness of other meshing gears reaches 25% of the original tooth thickness, and the open gear reaches 30%.
		28	Run reducer seal check	No seepage or oil leakage
		29	Key connection check	The keys and keyways must not be loose or deformed
		30	Worn state of the shaft	Wear ≤ 2% of the original shaft diameter
		31	Bearing inspection	Whether it is coated with grease; there must be no damage; the installation must not be loose.
		32	Oil seal inspection	There must be no aging and deterioration; the contact surface with the shaft or hole must not have harmful damage.
		33	Gear coupling inspection	It should be scrapped when one of the following situations occurs: crack; broken tooth; tooth thickness wear reaches 20% of the original tooth thickness
		34	Wheel surface quality inspection	It should be scrapped when one of the following situations occurs: cracks; rim thickness wear reaches 50% of the original thickness; rim thickness bending deformation reaches 20% of the original thickness; tread thickness wear reaches 15% of the original thickness; when the operating speed ≤50m/min When the roundness reaches 0.5mm
		35	Diameter difference of wheels on both sides	Tread diameter difference ≤1%
		36	Worn state of the wheel axle	Wear ≤ 2% of the original shaft diameter
		37	Bearing inspection	There must be no breaks or cracks
	Bridge	38	Span deviation△S	S≤10m; △S=±2m S＞10m; △S=±［2+0.1(S-10)]mm and △Smax≤±10mm
		39	Diagonal difference of bridge	K≤3m; ︱S1-S2︱≤5mm K＞3m; ︱S-S2︱≤6mm (S1, S2—diagonal wheel distance)
		40	Wheel focus point height difference△h	S≤10m; △h=±2.5mm 10＜S≤15m; △h=±3.5mm 15＜S≤20m; △h=±4.5mm 20＜S≤25m; △h=±5.5mm
Electric hoist electric hoist	Electric motor	41	Motor temperature rise inspection	For E-class insulated motors, the temperature rise does not exceed 115°C
	Electric motor	42	Motor abnormality inspection	Check whether the motor is reluctant to start or has abnormal noises
	Brake	43	Braking performance check	The braking performance should be safe and reliable, and the braking should be sensitive
		44	Quality inspection of brake parts	The brake parts should be scrapped and replaced when one of the following situations occurs: crack; brake lining (flat brake ring, tapered brake ring or pad type brake pad) thickness wear reaches 50% of the original thickness; spring (spiral type) , Disc spring, etc.) plastic deformation; the diameter of the small shaft or shaft hole wears up to 5% of the original diameter
		45	Brake wheel quality inspection	The brake friction surface of the brake wheel should not have defects that hinder the braking performance or be contaminated with oil; the scrap standard of the brake wheel : crack; the thickness of the rim of the lifting brake wheel is 40% of the original thickness, and the brake wheel is operated Up to 50%; unevenness of the wheel surface up to 1.5mm.
	reducer	46	Installation status check	The connecting bolts must not be loose
		47	Visual inspection of reducer	No damage or defects
		48	Seal quality inspection	No oil leakage
		49	Exception check	No abnormal sound; abnormal fever
		50	Gear quality inspection	Gear scrap standard: cracks; broken teeth; tooth surface pitting wear reaches 30% of the meshing surface, and the depth reaches 10% of the original tooth thickness (running gear is 15%); the tooth thickness of other meshing gears reaches the original tooth thickness. 20% (25% for running gears), 30% for open gears
		51	Inspection of other parts of reducer	The key connection must not be loose or deformed; the wear of the gear shaft is less than 1% of the original shaft diameter; the wear of other shafts is less than 2% of the original shaft diameter; the bearing must not have cracks and wear; the oil seal must not be aged or deteriorated, and contact with the shaft hole There must be no harmful damage on the surface;
	Reel device	52	Inspection of the fixed state of the end of the wire rope	The bolts on the end of the steel wire rope on the drum shall not be loose or abnormal
		53	Check the fixed state of the rope guide	When the empty hook is lowered, the wire rope should be freely discharged from the rope outlet of the rope guide
		54	Reel scrap standard	The drum is scrapped when one of the following situations occurs: crack; the drum wall wears up to 20% of the original thickness
	pulley	55	Visual inspection of pulley groove	The pulley groove should be smooth and clean, and there should be no defects that damage the wire rope
	pulley	56	Casting pulley scrap standard	It should be scrapped when one of the following situations occurs: cracks; uneven wear of the wheel groove up to 3mm; wheel groove wall thickness wear up to 20% of the original wall thickness; due to wear, the bottom diameter of the wheel groove is reduced by 50% of the wire rope diameter; other damages Defects of wire rope
	Wire rope	57	Wire rope lubrication status inspection	The wire rope should be kept in good lubrication condition
	Wire rope	58	Wire rope scrap standard	For the specific requirements of wire rope scrapping, please refer to GB5972-86 “Practical Specification for Wire Rope Inspection and Scrapping for Hoisting Machinery”. The safety level inspection and scrapping content of wire rope mainly include the following aspects: the nature and quantity of the wire rope; the broken wire at the end of the rope; broken Local gathering of wires; increasing rate of broken wires; strand breaks; rope diameter reduction caused by strand damage; reduced elasticity; external and internal wear; external internal corrosion; deformation; damage due to heat and arc
	Carrying chain	59	Chain appearance inspection	No obvious corrosion
	Carrying chain	60	Chain scrap standard	One of the following conditions should be scrapped: cracks; plastic deformation of the chain, elongation to 5% of the original length; the diameter of the chain ring wears to 10% of the original diameter
	Hook	61	Hook scrap standard	It should be scrapped if one of the following occurs: crack; the dangerous section wears up to 10% of the original size; the opening degree is increased by 15% than the original size; the torsional deformation exceeds 10%; the dangerous section or the neck of the hook appears plastic deformation
	Running wheel	62	Scrap Standard for Wheels of Hoist Traverse Trolley	One of the following conditions should be scrapped: crack; rim thickness wear reaches 50% of the original thickness; tread wear reaches 5% of the maximum diameter of the original tread
	Running wheel	63	Clearance limit between wheel flange and I-steel flange	The maximum gap shall not be greater than 50% of the width of the wheel tread
Electrical parts	Power lead-in device	64	Safety inspection of feeder bare wire	Annual inspection requirements 57th, 58, 59, 60, 61 monthly inspection requirements of the same month
		65	Sliding surface inspection
		66	Insulation device inspection
		67	Flexible cable entry device inspection
		68	Trolley wire safety device inspection
	Collector device	69	Wear state	Annual inspection requirements The 62, 63, 61, and 65 monthly inspection requirements of the same month The annual inspection requirements The 62, 63, 61, and 65 monthly inspection requirements of the same month
		70	Fixed state
		71	Rotation state of collector pulley
		72	Current collector spring inspection
	Internal wiring	73	Wiring appearance inspection	Annual inspection requirements The 66th, 67th, 68th, and 69th monthly inspection requirements of the same month
		74	Fixed state
		75	Flexible cable movement inspection
		76	Flat cable expansion performance inspection
	Electromagnetic contactor	77	Contact and core inspection	Annual inspection requirements The 70th, 71st, and 72th monthly inspection requirements of the same month
		78	Wiring fixed state inspection
		79	Contactor action check
	Flashlight gate	80	Visual inspection	Annual inspection requirements The 73rd and 74th monthly inspection requirements of the same month
	Flashlight gate	81	Fault and abnormal inspection
	Lifting limit switch	82	Action check	Annual inspection requirements The monthly inspection requirements of items 75, 76, 77, 78 are the same
		83	Contact check
		84	Wiring fixed state inspection
		85	Limit position check
Test run	No-load test run	86	No-load test run	As the cart runs back and forth, the cart moves horizontally, hoisting and descending actions, check for abnormalities, and whether the action conforms to the button mark
	No-load test run	87	Safety device inspection	Check whether the safety devices such as the lifting limit switch and the operating limit switch are sensitive, safe and reliable
	Load test	88	Rated load test	The vertical deflection of the main beam shall not exceed the specified value in the corresponding standards of various hoist cranes
		89	Overload test	Lift the vehicle with 25% overload. After unloading, the main beam must not have permanent deformation, cracks, peeling paint, looseness, damage, etc.
		90	Dynamic load test 1	Lifting 1.1 times the rated load and mid-span, only lifting and lowering and cart operation, various mechanisms within the specified time should be flexible, stable and reliable, no abnormalities