Overhead crane comparison: Single girder overhead crane or double gird

Single girder overhead crane, double girder overhead crane, which do you select? What is the similarities, differences, features of each type of overhead cranes? Check the comparisons of single girder overhead crane manufacturer and double girder overhead crane on working conditions, operation features, production cost, and mechanical properties, etc.

Overhead crane
An overhead crane, commonly called a bridge crane, is a type of crane found in industrial environments. An overhead crane consists of parallel runways with a traveling bridge spanning the gap. A hoist, the lifting component of a crane, travels along the bridge.

Generally, the overhead crane can be divided into two types: Single girder overhead crane, and double girder overhead crane. So how to choose it? This is a question that makes our customer confused.

Single girder overhead crane and double girder overhead crane somparison

Double girder overhead crane v.s. single girder overhead crane

Single girder overhead crane v.s. double girder overhead crane
Some details below can help you to choose the suitable overhead crane for your workshop, if you want to know more, please come to our website and there our engineer can design the unique drawing for your actual workshop.

On overhead crane working condition
Single girder overhead crane is generally used in the small place with short span, light weight, the working duration is not too long.
Double girder overhead crane is applicable to the big workshop shop and the working class will be high which can adapt the heavy capacity and big span. In contrast to the single girder type, the double girder application is more widely.
On overhead crane struction features
Single girder type overhead crane has light dead weight, simple construction features which is easy installation, disassembly and operation.
The weight of double girder type overhead crane is heavy and the construction features are complicated so its installation is a little harder than the single girder type.
On overhead crane manufacturing cost
For the manufacturing cost, the main influence factors are lifting capacity and span of the crane. Single girder type, the span and capacity are smaller than double girder type so its materials, technology, labor and production time are less than the double girder type. Therefore, single girder manufacturing cost is lower than double girder type.

On overhead crane operation objects
General operation of the single girder type is pendent control and remote control, but for the double girder type especially the crane with special slings such as grab, magnet and so on which needs the professional operator to control it.

Single girder design vs. double girder design
Single girder overhead crane have only one main girder across the span.
Double girder overhead crane have 2 main girders across the span.
On overhead crane travelling mechanism
Single girder overhead crane consists of electric hoist travelling on lower flange of crane girder and not required rail for cross traveling.
Double girder overhead crane is consisted of a crab mechanism travels above both girders run over cross travel rails with platform to maintain all parts of crab.
On overhead crane platform
Single girder overhead cranes generally have no platform for maintenance, or have 2 small platform for LT mechanism maintenance.
Double Girder Cranes have both sides’ platform across the main girders for maintenance purpose and platform for crab maintenance.
On overhead crane bridge light
Single girder overhead crane does not consist under bridge light.
Double Girder cranes have under bridge light for illusion to work in night.
On overhead crane motor differences
Single girder overhead crane have Flange mounted motors and vertical gearboxes for MH, CT and LT movements.
Double Girder overhead crane have foot mounted motors with Horizontal gearboxes.
On overhead crane controls
Single girder overhead crane can be operated through pendent and Radio Remote but they cannot operated through operating cabin.
Double girder overhead cranes can be operated by pendent, Radio Remote and operating Cabin, all operation mode is available.
On overhead crane brakes
Single girder overhead crane do not consist Electro Hydraulic thruster brakes due to its construction, there is DC Disc Brake used in all motions.
Mostly EOT Cranes have EHT Brakes and a combination of EHT+DC Disc Brakes used, there is no limitation of using Brakes.
On overhead crane limited switch
In Single girder overhead crane we used snap action limit switch which initiate by a wire rope guide for limiting Hoists movement in up and down motion.
In Dongqi EOT Cranes we used Rotary Limit switch which have a geared system to calculate hook travelling and limit it in up and down movement accordingly, there is an additional limit switch also placed as gravity limit switch to double secure limit switch working and protection.
On overhead crane capacity and spans
Single Girder overhead cranes used mostly upto 20 mtr span and 25T capacity for normal working.
Double Girder overhead cranes can be used from 1Ton to more than 500 Ton as per requirement.
On overhead crane duty classifications
Single girder overhead crane used mostly in light applications for handling normal material with standard working conditions.
Double Girder overhead cranes used in all type of applications for handling material and even in very critical atmosphere like cement, steel and oil and Gas.
On overhead crane wheels
Single girder overhead crane designed with 4 wheel arrangement in LT End carriage so have higher wheel load and required heavy gantry girder comparatively for same capacity.
Double Girder overhead cranes can be designed with 8 wheel arrangement so wheel load at a particular point is lesser so gantry girder structure will be light comparatively.
On overhead crane maintenances
These cranes is difficult for maintenance point of view but cheaper at price basis.
These cranes are easy in maintenance but costly at price basis.
Overhead crane comparison: Single girder overhead crane or double girder overhead crane?