In factories, workshops, warehouses, and small processing lines, single girder overhead cranes are one of the most widely used and cost-effective lifting solutions for light and medium-duty applications.
During the selection process, many buyers are often confused by various technical parameters, unable to distinguish between models or properly match the crane with their actual working conditions. Choosing an oversized crane may increase the investment cost, while selecting insufficient lifting capacity or span may result in long-term overload operation and create potential safety risks.
Based on practical application experience, crane manufacturer supply standards, and common issues encountered during customer purchasing, this guide explains the definition, working principle, key parameters, applicable working conditions, and selection considerations of single girder overhead cranes, helping buyers make a more suitable choice.
What Is a Single Girder Overhead Crane?
A single girder overhead travelling crane uses a single steel beam as the main girder, with an electric hoist for lifting and handling loads.
The main components include:
Main girder
End carriage
Electric hoist
Travel mechanism
Electrical control system
During operation, the electric hoist moves along the main girder to complete the transverse movement of materials, while the entire crane travels longitudinally along the runway rails of the building through the end carriages on both sides.
Single girder overhead cranes feature a simple structure, low self-weight, lower requirements for building load capacity, easy installation, and reduced maintenance costs.
Common applications include factory workshops, warehouse areas, assembly lines, machining areas, and equipment maintenance workshops.
Working Principle of a Single Girder Overhead Crane
Many operators are familiar with equipment operation but have limited knowledge of the internal operating principles, which can make equipment inspection and troubleshooting more difficult. A single girder overhead travelling crane mainly completes lifting operations through the following three steps.
Supporting Structure
The main girder and end carriages form the crane frame, which is installed on the runway rails of the workshop. The load of the lifted material is transferred through the main girder to the steel columns and runway structure of the building, ensuring stable crane operation.
Power Drive Components
The electric hoist is equipped with a lifting motor and trolley travel motor to achieve vertical lifting and horizontal movement along the main girder. The travel motors installed on the end carriages drive the entire crane to move forward and backward along the workshop runway rails.
Electrical Control System
The crane uses a wired pendant controller or wireless remote control to operate the start, stop, and direction control of each motor. Safety devices such as limit switches, buffers, and overload protection systems are installed to prevent overload operation and over-travel.
A single girder overhead crane operates through the coordination of three main movements: the electric hoist traveling horizontally along the girder, the crane traveling longitudinally along the runway rails, and the load moving vertically. These combined actions allow the crane to complete lifting, positioning, and stacking operations within the workshop span, making it widely used for indoor fixed-position lifting applications.
Key Purchasing Advantages of overhead crane single girder
For lifting equipment selection in small and medium-sized factories, overhead crane single girder have become a mainstream choice for light-duty lifting applications due to their four key advantages: low cost, space saving, fast installation, and easy maintenance. They are highly suitable for small and medium-sized enterprises seeking cost reduction and improved operational efficiency.
Lower Equipment Cost
The crane adopts a lightweight single girder structure, requiring less material and featuring a simpler design. Under the same lifting capacity and span conditions, its purchasing cost is significantly lower than heavy-duty cranes such as double girder overhead cranes. For intermittent and regular light-duty lifting operations in workshops, it can meet daily lifting requirements without high equipment investment, effectively controlling capital expenditure.
Suitable for Low-Headroom Workshops
With a compact structure and low overall height, the crane combined with a side-mounted electric hoist requires minimal vertical space and effectively increases the available lifting height. It can be directly installed in old workshops and facilities with limited headroom without modifying the building steel structure. It also does not occupy ground working space, making it an ideal solution for space-limited small and medium-sized workshops.
Easy Installation
The crane features a modular integrated design with standardized components that are easy to transport, assemble, and disassemble. No complex welding work is required on site, resulting in fewer installation procedures, simple commissioning, and lower labor costs. The crane can be commissioned and put into operation within a short period, significantly reducing the equipment installation cycle.
Easy Maintenance and Low Operating Costs
The simple structure of the crane reduces the risk of mechanical failures, while its core components offer high interchangeability and affordable replacement costs. Routine maintenance tasks such as inspections, lubrication, and fastening can be completed by general equipment operators. Fault diagnosis and repair are also relatively simple, minimizing downtime and significantly reducing long-term maintenance costs and production losses.
Applications of Single Girder Overhead Cranes
Single girder overhead cranes are suitable for light and medium-duty loads and intermittent operations. With outstanding cost-effectiveness, they are widely used in indoor working environments of small and medium-sized factories.
Machining Workshops
In hardware, machine tool, and mold manufacturing workshops, single girder overhead cranes are used for lifting molds, transferring workpieces, equipment assembly, and material handling. The commonly used lifting capacity ranges from 2 tons to 10 tons. With medium operating frequency, single girder cranes are an ideal choice for these applications.
Warehouses and Logistics Facilities
In raw material warehouses, finished product storage areas, and logistics facilities, operations such as material stacking, loading and unloading, and storage transfer are usually intermittent. These applications require equipment with stable performance and reasonable cost, making them one of the most common application scenarios for single girder overhead cranes.
Light Industry, Chemical, and Food Industries
Applications include light product assembly, maintenance of small chemical equipment, and handling of food processing machinery. These working conditions usually involve lighter loads and require smooth operation and low noise levels. Single girder overhead cranes can meet the requirements of light-duty lifting operations in clean workshops.
Paper Manufacturing and Building Materials Industries
Single girder overhead cranes are commonly used for handling paper rolls, building material panels, and other production materials. They provide stable operation and meet the lifting requirements of production line material handling.
Working Conditions Not Recommended for Standard Single Girder Cranes:
Standard single girder electric overhead travelling cranes are not recommended for outdoor operations, severe high-temperature or high-dust environments, 24-hour continuous heavy-duty operations, or large-span workshops. For these applications, specialized cranes or double girder overhead cranes are recommended.
High-Risk Prohibited and Restricted Working Conditions
Single girder overhead cranes are suitable for most indoor light and medium-duty lifting applications. However, due to limitations in structural strength, self-weight, and protective configurations, certain working conditions are strictly prohibited. During the selection process, high-risk applications must be avoided to prevent equipment damage, safety accidents, and failure to pass acceptance inspections, which may delay production.
1. Prohibited for 24-Hour Continuous High-Frequency Heavy-Duty Operations
Single girder electric overhead travelling crane are designed for intermittent and medium-duty operations, typically suitable for standard 8-hour daily production schedules. If the crane is used for continuous heavy-load lifting on an uninterrupted production line, the main girder may suffer fatigue damage, while the motor may overheat and the braking system may fail. This can lead to issues such as girder deformation and wire rope breakage. High-frequency continuous operations should use heavy-duty crane models.
2. Prohibited for Direct Outdoor Use Without Protection
Standard single girder overhead cranes are not equipped with rainproof, windproof, or corrosion-resistant protection features. Outdoor exposure to rain, sunlight, and strong winds may cause steel structure corrosion, electrical moisture damage and short circuits, as well as brake failures. Strong winds may also cause load swinging and crane movement. Outdoor applications require specially designed outdoor crane models with appropriate protection systems.
3. Prohibited for High-Temperature, High-Dust, and Highly Corrosive Environments
Standard single girder overhead traveling crane are not suitable for high-temperature metallurgical workshops, high-dust environments, or chemically corrosive facilities. High temperatures can reduce the performance of steel structures and accelerate electrical component aging. Dust accumulation may block motors, limit switches, and brakes, causing operational failures. Acidic and alkaline media can corrode the main girder and components, significantly reducing equipment service life. These working conditions require customized crane versions with high-temperature resistance, dust protection, and corrosion resistance.
4. Prohibited for Excessive Span, Long-Term Maximum Load Operation, and Overloading
The load-bearing capacity of a single girder is limited. Under large-span conditions, the main girder may experience excessive deflection, reducing operational stability. Overloading is strictly prohibited, and long-term lifting at the maximum rated capacity should also be avoided. Even short-term overload operation can damage the structure and create potential safety risks. Large-span and heavy-duty applications require properly matched crane models.
Single Girder Overhead Crane Selection Guide
Crane selection does not require endless comparisons. By focusing on key factors such as actual working conditions, workshop conditions, operating frequency, and budget, most purchasing issues can be avoided.
1. Lifting Capacity:
First, confirm the maximum lifting weight required on site. During selection, a safety margin of 1.2 times the actual load should be considered. Small parts handling usually requires 1–5 tons; molds and medium-sized workpieces typically require 10–16 tons. Reinforced customized single girder designs can reach up to 32 tons. For capacities above this range, single girder cranes are not recommended to avoid potential safety risks.
2. Workshop Conditions:
Span:Standard LD single girder overhead cranes are suitable for spans within 20 meters. For spans between 20 and 31.5 meters, reinforced customized main girders are required.
Available Headroom:For workshops with limited building height, an LDP low-headroom electric hoist configuration can be considered. This design reduces the vertical space occupied by the hoist and provides greater effective lifting height.
Building Load Capacity:For older workshops, wheel loads must be calculated in advance, and the load-bearing capacity of the building columns must be checked to ensure compatibility with the crane's self-weight and operating loads.
3. Operating Frequency (Duty Classification):
The duty classification represents the fatigue resistance level of the crane, not the rated lifting capacity. It is determined by daily operating hours and load cycle frequency.
A3 (Light Duty):Suitable for low-frequency intermittent operations with daily usage of ≤3 hours. The crane remains idle most of the time, and standard configurations are sufficient. It offers the best cost-effectiveness and is suitable for occasional lifting and maintenance applications.
A5 (Medium Duty):Suitable for regular medium-frequency operations with daily usage of 4–8 hours. For frequent lifting and routine workshop production, the crane features reinforced main girder plates, upgraded motors and braking systems, and improved fatigue resistance. It is the most commonly used duty class in factories.
Single girder overhead traveling crane are not recommended for high-frequency 24-hour continuous operation cycles.
4. Control System Selection:
For simple lifting operations in standard workshops:Wired pendant control is recommended due to its low cost and high reliability.
For dusty environments or long-distance operation:Wireless remote control is preferred, providing more convenient operation, allowing operators to stay away from suspended loads, and improving safety.
For precision assembly applications:Variable frequency drive (VFD) control can be selected to reduce load swing and achieve smoother operation.
5. Budget and Equipment Quality:
For standard applications in small and medium-sized enterprises:
Choose standard-compliant crane models that meet special equipment inspection requirements and provide high overall cost performance.
For projects requiring long service life and high stability:
Upgrade key components by selecting standard-compliant motors, reinforced main girders, and reliable electric hoists. Avoid non-standard equipment with reduced configurations to minimize future failures and maintenance costs.
Common Pitfalls to Avoid When Purchasing a Single Girder Overhead Crane
Many companies only compare lifting capacity and price when purchasing single girder overhead cranes, while ignoring actual working conditions, equipment configurations, and national standards for special equipment. This often leads to problems such as equipment being unusable after delivery, failure to pass acceptance inspection, and frequent breakdowns. Based on practical project experience, the following are common purchasing mistakes to avoid.
1. Pursuing the Lowest Price Only
Low-cost non-standard products on the market often reduce the thickness of main girder plates, falsely increase motor power ratings, downgrade wire rope specifications, or omit certain safety limit devices. Although the initial purchase cost is lower, insufficient structural strength and incomplete safety configurations can lead to higher failure rates and safety risks. The later costs for repairs and component replacement may far exceed the initial savings. Buyers should prioritize standard-compliant products with complete configurations and avoid non-standard cranes with reduced specifications.
2. Focusing Only on Lifting Capacity
Many buyers only consider the rated lifting capacity while ignoring the load-bearing capacity of workshop columns and runway rails. Under the same lifting capacity, cranes with different spans can have significant differences in self-weight and wheel loads. The load-bearing capacity of older workshops is often limited. Without calculating wheel load parameters in advance, problems such as insufficient building load capacity may occur after installation, preventing acceptance approval and production operation, resulting in equipment limitations and wasted investment.
3. Ignoring Actual Working Environment
Special working environments such as humid areas, high-dust workshops, locations with flammable or explosive materials, and applications requiring low-noise operation cannot directly use standard crane models without consideration. Poor adaptability and frequent failures may occur. For example, chemical facilities require explosion-proof components, while humid environments require corrosion-resistant and waterproof treatments. During selection, the crane should be matched with actual site conditions and equipped with appropriate protection configurations when necessary.
4. Excessively Increasing Capacity and Configuration
Crane selection should include a reasonable safety margin of 1.2 times the actual load requirement, but this does not mean unlimited increases in lifting capacity or duty classification.
Some buyers choose larger-capacity and higher-duty-class models simply to leave additional capacity margin, even when they exceed actual lifting requirements. Using heavy-duty high-grade equipment for light-load intermittent applications increases initial investment costs, while also increasing energy consumption and long-term maintenance expenses. This results in excessive equipment performance. The most reasonable approach is to select a crane that matches the actual operating conditions.
5. Ignoring Installation Qualifications and After-Sales Service Capability
Cranes are classified as special equipment, and their installation, acceptance inspection, and periodic inspections require qualified certifications. Some small manufacturers lack professional installation teams and complete after-sales support systems. Improper installation procedures may create safety hazards, while insufficient maintenance support after equipment failures may prevent timely repairs and assistance with periodic inspections. Before purchasing, buyers should confirm the manufacturer's special equipment installation qualifications and after-sales service capabilities to ensure compliant and reliable crane operation.
Equipment Operation and Maintenance Guidelines
The service life, operational stability, and compliance of a single girder overhead crane depend not only on the equipment quality itself but also on proper operation and regular maintenance. Standardized operation and maintenance can extend equipment service life, reduce failures, ensure smooth completion of special equipment inspections, and prevent potential safety risks.
1. Daily Operation Guidelines
Operators must hold valid qualifications and be familiar with equipment operating procedures and safety requirements. Unauthorized operation and improper use are strictly prohibited.
Conduct a basic inspection before starting the crane, including checking the brake system, limit switches, wire rope, and hook condition. The crane can only be operated after confirming that no abnormalities exist.
Overloading, diagonal pulling, diagonal lifting, and dragging of workpieces are strictly prohibited during operation. Suspended loads must not pass over people, and lifting personnel is strictly forbidden.
Lifting and traveling operations should be performed smoothly. Avoid sudden starts, emergency stops, and rapid direction changes to prevent load swinging or falling.
If abnormal conditions such as unusual noise, jamming, electrical leakage, or brake failure are detected during operation, stop the crane immediately, disconnect the power supply, and perform troubleshooting. Continued operation with faults is strictly prohibited.
After daily operations, return lifting devices to their designated positions, disconnect and lock out the power supply, and complete operation records.
2. Regular Maintenance Requirements
Monthly Maintenance:
Clean the runway rails, end carriage travel mechanisms, bearings, and gears, and apply lubricating grease. Tighten all connecting bolts, inspect the main girder for deformation and weld cracks, test brake sensitivity, and adjust brake clearance to ensure smooth operation.
Annual Maintenance:
Conduct a comprehensive inspection of the main girder structure, wheel loads, and runway rail alignment. Replace aged wire ropes, electrical components, and sealing parts. Fully test and adjust safety protection devices, and cooperate with third-party inspection agencies to complete special equipment annual inspections, ensuring compliant crane operation.
3. Maintenance Practices to Avoid
Maintenance work with the power supply connected and troubleshooting of faulty equipment while in operation are strictly prohibited.
Do not remove or modify safety devices such as limit switches and overload protection systems without authorization.
Avoid long-term operation without regular inspections or lubrication, and do not continue heavy-load operation with equipment faults.
Non-professional personnel are prohibited from disassembling core crane components to prevent equipment damage and failure of safety protection systems.
Conclusion
Single girder overhead cranes are the mainstream lifting equipment for light and medium-duty workshop applications. With advantages such as high cost-effectiveness, simple structure, easy installation, and low maintenance costs, they are suitable for regular lifting operations in most small and medium-sized factories.
The key principle of crane selection is to base the decision on actual working conditions and properly match the four main parameters: lifting capacity, span, lifting height, and duty classification. The crane model should also be selected according to the workshop conditions. Avoid unnecessary high-end configurations and low-cost non-standard products. Focusing on safety, reliability, and practicality is the key to selecting compliant and durable lifting equipment.
FAQ
Q: What is the maximum lifting capacity of a single girder overhead travelling crane? How long is its service life?
A: The maximum lifting capacity of standard models is 16 tons, while reinforced customized main girder versions can reach up to 32 tons. Overloading beyond the rated capacity is strictly prohibited. Under compliant working conditions, A3 duty class cranes typically have a service life of 8–10 years, while A5 duty class cranes can reach 10–15 years.
Q: Is a single girder overhead crane classified as special equipment? Is regular inspection required?
A: Yes. It is legally classified as special equipment and must be registered and inspected regularly. After the installation of a new crane, it must pass inspection and obtain the required operation certificate before being put into service. Once in operation, the crane must undergo annual inspections.
Q: Can a overhead crane single girder be installed in a workshop with limited headroom?
A: Yes. Standard LD-type single girder cranes require more vertical installation space. For workshops with limited headroom, LDP low-headroom side-mounted single girder overhead cranes are recommended. The side-mounted electric hoist design reduces vertical space requirements and is suitable for low-height workshop applications.
Q: Can a single girder overhead crane be used outdoors?
A: Standard indoor models are not suitable for outdoor operations. Outdoor applications require customized outdoor crane models equipped with rainproof, dustproof, sunproof, and lightning protection components. Using standard models outdoors may cause moisture damage to the motor and electrical systems.
Q: Why do prices vary significantly for single girder overhead traveling cranes with the same lifting capacity?
A: The price difference mainly depends on whether the crane meets national standards, steel plate thickness, component configuration, duty class, and manufacturing process. Low-cost non-standard products often use thinner main girders, low-quality motors, and lack proper inspection procedures, resulting in higher safety risks. Standard-compliant products feature inspected main girders and high-quality components, providing better safety and durability.
Q: How can excessive load swinging during lifting operations be reduced?
A: Load swinging is mainly caused by excessive starting and stopping speeds or the lack of speed control functions. A variable frequency drive (VFD) system can be installed to achieve smooth acceleration and deceleration. Proper operating procedures should also be followed by avoiding sudden starts, emergency stops, and rapid direction changes to reduce load swinging.
Q: Can a single girder overhead crane be installed in an old workshop?
A: Yes, but the structural strength of the workshop columns must be inspected before installation, and wheel loads must be calculated to select a suitable lightweight crane model. If the building load capacity is insufficient, the supporting structure must be reinforced before installation to ensure safe operation.
