FAT vs SAT: What Is the Practical Difference for Crane Acceptance?
In the crane acceptance process, FAT factory acceptance testing and SAT on-site acceptance testing are the two key links to control the quality of equipment and ensure compliance with production, which are directly related to the adaptability of equipment working conditions and production safety.In the industry, there is a widespread problem that equipment successfully passes the factory acceptance of the factory, but fails the on-site factory acceptance, which can easily lead to hidden dangers such as delays in construction, increased rectification costs, and project acceptance disputes.Clarifying the practical differences between the two, the focus of testing and the cause of failure are the core keys for all parties to control the quality of acceptance and avoid project risks.
FAT vs. SAT: What Is the Difference?
FAT is the factory acceptance test, which is the compliance acceptance completed in the manufacturer's standardized workshop before the crane leaves the factory.Relying on a stable and controllable production environment and professional testing equipment, it focuses on verifying equipment parameters, steel structure dimensions, electromechanical functions and a full set of factory information, and completes standard load tests to comprehensively inspect equipment manufacturing accuracy and factory performance, investigate assembly, welding, parts and functional defects, and lock in the original manufacturing quality of the crane from the source. It is the core standard for qualified equipment to leave the factory.
SAT is the on-site acceptance test, which is the final acceptance carried out at the actual working conditions of the project after the crane is installed and debugged on the site.It focuses on the on-site adaptation capabilities of the equipment, conducts a comprehensive verification of the track accuracy, installation quality, on-site power supply, and control system linkage effects, and conducts full-load operation tests in combination with the real operating environment to verify that the equipment can be adapted to complex on-site working conditions, stable, safe, and compliance operation, which is the final acceptance basis for the crane to be officially put into operation.
What Should Be Checked During Crane FAT?
The factory acceptance of crane equipment is the first line of defense to control the original quality of the equipment. The core is to investigate all hidden dangers in the manufacturing process and prevent unqualified equipment from leaving the factory.The whole process of acceptance revolves around drawing standards and industry specifications. The core inspection dimension includes four major sectors, each of which is required for factory acceptance.
Crane specifications and documentation
The verification of data and parameters is the first step in the acceptance of equipment, and it is also the basic certificate of equipment compliance.The acceptance personnel need to check one by one whether the parameters, parts models, and technical configurations of the crane machine 100% match the contract requirements and design drawings, and focus on checking the core parameters such as rated lifting weight, span, lifting height, working level, and operating speed to eliminate problems such as parameter shrinkage, configuration replacement, and model discrepancy.At the same time, it is necessary to complete the verification of a full set of factory information, including equipment drawings, parts drawings, material certificates, factory certificates, parts inspection reports, electrical schematic diagrams, hydraulic system drawings, operation and maintenance manuals, third-party type test certificates, etc.All information must be true, complete, and traceable. Missing information, inconsistent parameters, and expired certificates are all judged to be unqualified for FACTORY acceptance, and the equipment is prohibited from leaving the factory.
Structural and dimensional inspection
The structural and dimensional inspection directly determines the structural stability and carrying capacity of the Henan Mine Crane Factory supply crane, which is the core hardware inspection item of the company.Focus on testing the welding quality and forming accuracy of core steel structures such as the main beam, end beam, frame, and lifting arm, investigating welding defects such as weld pores, slag, cracks, and non-penetration, and checking that the surface of the steel structure is free of deformation, rust, and bump damage.The dimensional accuracy verification needs to strictly control the drawings to detect key dimensions such as crane span, track gauge, diagonal deviation, main beam arch, side curvature, wheel parallelism, etc. All deviations must be controlled within the allowable error range of the industry.The dimensional deviation of the steel structure exceeds the standard, which will directly lead to the operation of the equipment, uneven force, and late structural deformation, which is a major hidden danger in the quality of the factory.
Mechanical and electrical functions
The mechanical and electrical systems are the core power and control core of the crane's operation, and the acceptance of the crane requires the completion of the full-featured no-load test and simulated working condition test.The mechanical system focuses on detecting the operating status of the lifting mechanism, operating mechanism, luffing mechanism, and rotary mechanism, investigating faults such as start-stop caton, abnormal noise, jitter, brake lag, and slippage, and checking the assembly accuracy and operating flexibility of moving parts such as reducers, couplings, wheels, and reels.The electrical system focuses on the performance testing of control cabinets, frequency converters, contactors, cables, and limit control systems to verify electrical circuit wiring specifications, no short circuits, and no virtual connections, and the control system is responsive and accurate in operation.At the same time, the linkage functions of various institutions are tested to ensure that the mechanical and electrical systems of the whole machine are matched smoothly, with no functional defects and no control failures.
Safety devices and load testing
Safety device and load testing are the top priorities of equipment acceptance, which are directly related to the safety of equipment operation.It is necessary to fully verify all safety protection devices, including overload limiters, height limiters, stroke limiters, buffers, emergency stop devices, windproof devices, brakes, etc., To test all safety devices with sensitive trigger, reliable action, and accurate parameters, which can effectively avoid safety risks such as overload, over-range, and collision.The load test is carried out in strict accordance with industry standards, and the dynamic test of 100% rated load and the static test of 125% rated load are completed to test the carrying stability of the equipment, structural deformation, and braking reliability. During the test, the equipment has no permanent deformation, no noise, no leakage, and the safety device is triggered normally, which means that the load test is qualified, and it is also the core basis for the acceptance of the equipment.
What Should Be Checked During Crane SAT?
On-site acceptance of crane equipment does not repeat the inspection of the factory manufacturing quality of the equipment. The core focuses on on-site installation quality, adaptability to working conditions, actual operating performance, and system integration effect, and verifies the compliance and practicality of the equipment in real operating scenarios. It is the final verification standard for the equipment to be officially put into operation.
Installation and runway conditions
Installation quality and track working conditions are the basic prerequisites for SAT acceptance, and they are also the links that are most prone to acceptance failures.Focus on verifying the installation accuracy of the crane machine, including equipment level, verticality, wheel fit, and fixed reliability of the machine, and troubleshooting problems such as misalignment of installation, poor fixation, and deviation of component assembly.At the same time, comprehensively inspect the state of the crane's operating track, verify the track flatness, straightness, gauge deviation, track fixed strength, and track joint clearance, and investigate problems such as track deformation, loosening, and height difference exceeding the standard.If the track working conditions are not up to standard, it will directly lead to deviation, rail gnawing, jitter, abnormal noise in the operation of the crane, and damage to the equipment structure in severe cases. It is a high-frequency unqualified item for SAT acceptance.
Power supply and control system
The on-site power supply conditions and the adaptability of the control system determine whether the Henan Mine Crane Factory supply crane can operate stably.For crane acceptance, it is necessary to test the stability of the on-site power supply voltage, current, and frequency, investigate voltage fluctuations, insufficient power supply, line overload, and poor grounding, and verify that the power supply system can meet the crane's full-load operation requirements without hidden dangers such as tripping, power failure, and abnormal voltage.For on-site control systems, it is necessary to test the switching sensitivity of remote control, local control, and linkage control, verify the adaptability of the control system to on-site electrical circuits, monitoring systems, and safety systems, and investigate signal delays, command failures, system errors, abnormal communication, etc. To ensure that the equipment control functions are adapted to the needs of on-site operations.
Load and operational performance
On-site load and operational performance testing is the core of SAT acceptance.Unlike FAT's workshop simulation load test, SAT uses on-site real working conditions to complete the full-dimensional test, and then carries out no-load test operation, half-load test operation, rated full-load test operation, and static verification of overload load.Monitor the operating status of all actions of the crane such as lifting, descending, walking, rotating, and luffing throughout the process, detect the stability, braking accuracy, and smooth operation of the equipment at full load, and investigate problems such as jitter, slippage, brake failure, and abnormal structural deformation at full load.At the same time, the continuous operation performance of the equipment is tested to verify that there is no trouble, no overheating, and no performance attenuation during long-term operation, and it is adapted to the needs of on-site normalization operations.
Site integration and final handover
On-site integration, adaptation and final handover are the finishing links of SAT acceptance.It is necessary to verify the compatibility of the crane with the on-site plant, supporting equipment, operating procedures, and safety protection system, and confirm that the operation of the equipment has no space interference, no operating conflicts, and complies with on-site safety management specifications.At the same time, complete a comprehensive re-inspection of the whole machine, sort out the minor defects and rectification problems found during the acceptance process, and confirm that all problems are closed-loop rectification.Finally, check the full set of acceptance information, rectification records, test reports, equipment spare parts, tool accessories, complete the multi-party signature confirmation, formally complete the on-site acceptance and handover of the equipment, and the equipment can be put into production legally and in compliance.
Why Can a Crane Pass FAT but Fail SAT?
In more than 60% of crane acceptance disputes in the industry, FAT is qualified and SAT is unqualified. The core reason is that the ideal environment for standardization of FAT is very different from the complex on-site reality of SAT.All factory-qualified equipment may have performance failures due to on-site variables, and the four core incentives cover 99% of the acceptance rollover scenarios.
Installation and runway alignment problems
The installation deviation and the track accuracy are not up to standard, which are the primary reasons for the failure of the FAT qualified SAT.When the crane is assembled in the manufacturer's workshop, it relies on precision tooling positioning, and the assembly accuracy and structural alignment are fully up to standard.However, the construction level of the on-site installation team is uneven, and it is prone to installation defects such as the installation tilt of the whole machine, the deviation of the wheel alignment, and the misalignment of the structural assembly.At the same time, the track construction on the project site is prone to problems such as gauge deviation, uneven track, excessive straightness, loose fixation, and misalignment of joints. These on-site working conditions cannot be reflected in the project acceptance.The structure of the equipment is qualified at the factory, but the adaptation to the unqualified track and installation accuracy will inevitably cause problems such as rail gnawing, deviation, abnormal structural force, and excessive load deformation during operation, which directly leads to the failure of SAT acceptance.
Site power and environmental differences
The difference between the power supply conditions and the on-site environment is the key invisible factor that causes the acceptance failure.The manufacturer's workshop has a high-quality power supply environment with stable voltage regulation, steady current, and standard grounding, which can ensure the stable operation of the crane's electrical system, control system, and power system, and there is no abnormality in the test.However, there are generally problems such as large fluctuations in the power supply voltage, unstable temporary power supply, irregular grounding, and insufficient line load at the project construction site, which can lead to errors in the crane inverter, insufficient motor power, control system failure, and false triggering of safety devices.At the same time, environmental factors such as on-site dust, temperature difference, humidity, and wind will also affect the operating stability of the equipment and cause SAT acceptance failures.
Control, communication, and integration issues
The problem of integration and adaptation of control systems, communication systems and on-site integration is a hidden danger of acceptance that can easily be ignored.FAT acceptance only tests the performance of the stand-alone control system of the equipment, and there is no need to connect other equipment and management systems on the site.However, the acceptance of the project requires the crane control system to be adapted to the on-site monitoring system, linkage equipment, safety management system, and remote operation and maintenance system.During the docking process of the on-site system, it is prone to problems such as mismatched communication protocols, delayed signal transmission, conflicting system instructions, and abnormal linkage logic, resulting in limited equipment functions, error shutdown, and failure of safety functions.Such software and integration problems cannot be detected at all in the factory FAT test, and can only be exposed in the on-site SAT acceptance.
Load testing under actual operating conditions
The difference in load test working conditions is the core and essential reason for the inconsistency between the two types of acceptance results.The FAT load test is carried out in a flat, stable and interference-free workshop environment. The equipment is subjected to uniform force and no external load interference. The test data is accurate and stable, and it is easy to meet the standards.
The on-site SAT load test relies on real operating scenarios, and there are multiple disturbances such as operating space constraints, wind influence, ground settlement, and track micro-deformation. The actual force state and load distribution of the equipment are completely different from the workshop test.Some equipment passed the simulated load test in the workshop, but under the real load conditions on the site, there will be problems such as excessive structural deformation, brake slippage, and abnormal response of safety devices, which eventually led to the failure of SAT acceptance.
How to Prepare for a Successful Crane FAT and SAT
In order to achieve one-time acceptance of crane FAT and SAT, and avoid rectification costs and construction delays, the core is to do a good job of pre-planning, process control, responsibility landing, and hidden danger pre-arrangement.From the early stage of production to the end of the site, the whole process is standardized and prepared, which can completely solve the problem of acceptance and rollover.
Define test procedures and criteria
The pre-acceptance standard is the core prerequisite for successful acceptance.Before the start of crane production at Henan Mine Crane Factory supply, both supply and demand parties need to combine the project contract, industry national standards, and on-site working conditions to clarify the factory acceptance process and SAT on-site acceptance process, and refine each test item, test method, data standard, and pass threshold.Lock the load test parameters, structural accuracy deviation range, safety device trigger standards, electrical system operation requirements, and on-site integration adaptation standards in advance to form a written acceptance plan.Eliminate problems such as vague acceptance standards, cognitive differences, and inconsistent standards in the later stage, so that the whole process of production, testing, and acceptance can be followed by rules.
Clarify all parties’ responsibilities
Clarify the rights and responsibilities of multiple parties, and avoid the problems of acceptance prevarication and missed inspections.Divide the core responsibilities of the purchaser, crane manufacturer, installation and construction party, third-party testing agency, and supervision unit in advance: the manufacturer is responsible for production quality, factory testing, rectification and optimization.The installer is responsible for on-site standardized installation and pre-commissioning.The purchaser is responsible for the preparation of on-site working conditions and power supply conditions.Third-party institutions are responsible for fair testing and data verification.All responsibilities shall be confirmed in writing, and the docking person in each link, the acceptance participation process, and the party responsible for the rectification of the problem shall be clarified, so as to avoid quality problems and prevarication after acceptance failures, and to ensure rapid response and efficient rectification of acceptance problems.
Prepare documents and checklists
Complete a full set of acceptance materials and problem lists in advance to ensure the efficient advancement of the acceptance process.During the production phase, a complete set of information such as equipment drawings, qualification certificates, test reports, parts and components certificates, and material certificates are simultaneously organized to ensure that the information is true and effective and consistent with the equipment parameters.At the same time, formulate FAT and SAT acceptance inspection forms and problem rectification lists in advance, and clarify the test items, eligibility criteria, problem recording methods, and time limit for rectification.During the acceptance process, test data, equipment status, and defects are recorded in real time, so that the problems can be traced and the data can be verified, and the acceptance lag caused by missing data and incomplete records can be eliminated.
Rectify all non-conformities
The whole process of closed-loop control of all unqualified items is the key to acceptance and customs clearance.In the factory acceptance stage, if any manufacturing, functional, or performance defects are found, they must be stopped immediately for rectification. All problems are 100% closed-loop and can only be shipped from the factory after passing the re-inspection. Resolutely prevent the entry of equipment with problems.In the on-site acceptance stage, for installation deviations, adaptation of working conditions, system failures, abnormal operation and other issues, they are registered in the rectification list one by one, and the rectification plan, rectification time limit, and re-inspection standards are clarified.After all the unqualified items have been rectified and the re-inspection meets the standards, the final acceptance and handover will be carried out to avoid the hidden dangers left by the acceptance from the root cause.
Henan Mine Crane Factory Custom Custom
FAT and SAT are the core dual guarantees for crane compliance delivery and safe operation. The former strictly controls the original manufacturing quality at the factory, while the latter verifies the on-site installation adaptation and actual operating performance. It is indispensable.As a professional crane manufacturer, Henan Mine Crane Factory implements standardized factory factory acceptance and SAT on-site acceptance control throughout the process, accurately avoiding acceptance failures, construction delays, operating failures and other issues, and using a strict quality inspection system to ensure that each equipment is of excellent quality and suitable working conditions, so as to help the project to be put into production efficiently and operate safely and stably for a long time.
