Basic Introduction of The Lifting Load Limiting Device

1. Definition

The lifting load limiting system is a safety device which avoid overload by sensing the lifting weight, as known as crane overload limiter or torque limiter

The composition of the lifting load limiting system

Lifting load limiting system is generally composed of two parts: Strain gage based load cell and weighing control indicator. The load cell is used to detect the lifting weight while the weighing control indicator provides the corresponding control signal by judging the lifting weight

 

2. Structural features

The lifting load limiting system can work with the lifting machinery effectively without any threat to the equipment security. Meanwhile, it is reliable, easy maintenance and high accurate.

 

The common structures are Lateral Pressure type, Shaft pin type, Bearing block type, Fish back type, Plate and hole type, etc.

 

3. Inspection Regulation of Lifting Machinery Safety Technique

The "Inspection Regulation of Lifting Machinery Safety Technique for Bridge Crane" (TSG Q2002-2008, hereafter referred as Regulation) came into effect in 2008, which including the following requirements:

 

（1）The in-use bridge cranes which are produced and installed before 2008-07-31, should meet the requirement of the regulation by modification or replacement, except for the cranes which are working with molten metal that must comply with the regulation。

 

（2）The electric hoist in bridge cranes which are produced and installed after 2008-08-01, should be equipped with lifting load limitings ystem and overcurrent(overload) protection device, except the hoists which are working with molten metal or pneumatic and electric anti-explosion that must comply with the regulation before 2009-04-01.

 

5. Product series

Model	Sensor structure	Suitable applications
H9Z1	Lateral Pressure Type	Engineering lifting equipment such as electric hoist, steel wire rope straight hoist, etc.
H9Z2	Lateral Pressure Type
H9X1	Shaft pin type	Tower cranes, hoists, rack construction hoists, port machinery, chain hoists, and occasions where other types of sensors cannot be installed
H9X2	Shaft pin type
H9X3	Shaft pin type
H9X4	Shaft pin type
H10B	Bearing blockt type	Bridge (gate) cranes, hoists, double lifting point cranes, main/auxiliary hook cranes, grab cranes and other occasions with bearing seat structure
HM9L	Fish back (Fixed pulley) type	Large tonnage bridge (gate) crane
B3L1	Plate ring type	Electric hoist, crawler crane, tower crane, etc.
H8C8	Shear beam type	Small tonnage engineering lifting equipment
H31A	Stype (parallel beam type)
FYB14	Pressure Sensor	Boom cranes and various equipment that need to measure hydraulic pressure