Gelenk-Manipulator für Körbe
Gelenk-Manipulator für Körbe
CATEGORY 05
HANDLING CHARGING RACK AND INFLUE BASKETS: ERGONOMIC OVEN LOADING IN THE HARDENING FACTORY
In the hardening shop, the handling of the batch determines throughput, quality, and employee health. Charging racks and annealing baskets are heavy, the workpieces come out of the furnace piping hot, and every cycle counts.
An empty charging rack weighs between 30 and 150 kg; fully loaded batches can weigh 300 to 800 kg or more. After austenitizing, the batch leaves the furnace with several hundred degrees of residual heat, and the transfer to the quenching bath is time-critical. Manual charging in this environment poses both a health and quality risk.
A lifting aid for heat treatment must accomplish three things simultaneously: guide heavy charging racks weighing up to 1,200 kg without swaying, reliably control temperatures at the receiving point, and operate dependably for decades in a hall with salt spray, oil vapor, and heat. Zeilhofer Handling Technology from Holzkirchen has been supplying precisely these specialized solutions for 25 years.
CHAPTER 1
What is a lifting aid for heat treatment?
A loading lifting aid for the hardening shop is a specialized handling solution for charging racks, annealing baskets, and individual workpieces. Three designs have become established: the ZH90 lifting axis for linear, pendulum-free lifting with a high load capacity of up to 1,200 kg, the articulated manipulator with a large working radius for loading multiple furnaces, and the cable manipulator for maximum reach across multiple stations.
For use in hardening shops, all three are equipped with heat-resistant mounts, salt- and oil-proof pneumatics, and robust sensors. Mounts that are in direct contact with the hot rack operate with temperature-resistant steel 1.4828 or high-temperature pads made of aramid and silicate.
CHAPTER 2
When is a lifting aid worthwhile in the hardening shop?
Four indicators reveal when manual charging reaches its limits and a technical lifting aid becomes economically viable.
01 Batches over 25 kg
Loaded charging racks exceed the DGUV load recommendations many times over. BG funding programs often support such investments.
02 Hot oven removal
Warm batches from hardening and tempering furnaces require heat-resistant coatings and thermally protected pneumatics.
03 Transfer to the cooling bath
Seconds determine the required quenching curve. Rapid, pendulum-free handling ensures reproducible results.
04 Warp-sensitive parts
Vibrations promote warping. A smooth, vibration-free process keeps workpieces in position and protects quality.
CHAPTER 3
Practical application: Loading of chamber and pusher furnaces
Requirements
Charging racks 100 to 800 kg, loaded with serial parts
Loading and unloading in short cycle times
Pendulum-free process over a 2 to 4 meter furnace line
Heat protection for operator and camera
Resistance to salt spray and oil vapor
ZHHT solution
A ZH90 lifting axis with a heat-resistant fork or clamp gripper picks up the charging rack and guides it smoothly to the furnace. A thermally insulated flow control opens and closes the holder, and the pneumatic system uses heat-resistant PTFE hoses. A protective shield reduces radiant heat at the operator's station.
Advantages of this application
Operator distance to heat source: 2 to 3 meters
Swing-free lifting even with an 800 kg load weight
Heat-resistant holder for oven removal
Salt and oil resistant pneumatics for long service life
Reproducible loading without physical strain
CHAPTER 4
Practical exercise: Transfer between oven and quench bath
Staggered according to temperature
Batch size 100 to 600 kg, residual heat 200 to 500 °C
Time-critical path to the oil or polymer bath
Fast, sway-free lowering into the bathroom
No vibration of the workpieces in the rack
Resistance to rising oil vapors
ZHHT solution
A jointed manipulator with a heat-resistant mount guides the batch smoothly and quickly from the furnace to the quenching tank and lowers it in a controlled manner. The movement guide holds the workpieces stably in position, ensuring that the required quenching time is reliably observed. The mount is protected against oil vapors and heat.
Advantages of this application
Short, defined transfer time for reproducible quenching
Pendulum-free lowering protects against delay
Heat-resistant holder for batches directly from the oven
A manipulator operates the oven and bathroom
Significantly reduced physical strain in the hottest workplace
CHAPTER 5
Practical application: Handling of individual large and heavy parts
Requirements
Individual workpieces weighing 50 to 1,200 kg, e.g. large gears, rings, shafts
Finished surfaces, no scratches allowed
Place in oven or rack, turn over for inspection.
Variety of options in one line
Precise positioning without pendulum action
ZHHT solution
A ZH90 lifting axis with a rotary gripper enables 360-degree rotation of the workpiece without repositioning. A component-specific gripper with a high-temperature-resistant surface gently grips defined areas. A quick-change interface allows gripper swapping for different workpiece types in under a minute; the control system stores up to 16 gripper variants.
Advantages of this application
A 360-degree turn without repositioning saves a work step.
Quick-change grippers for a wide variety of variants
Gentle handling protects processed surfaces
Memory for up to 16 gripper variants
Scalable to multiple furnaces and stations
CHAPTER 6
Engineering process step by step
Four indicators reveal when manual charging reaches its limits and a technical lifting aid becomes economically viable.
01 Initial consultation on site
Inspection of the hardening shop, recording of batch weights, temperatures, cycle times and furnace interfaces.
03 Detail Engineering
3D CAD, FEM calculation, safety analysis according to EN ISO 13849 PL d, pneumatics with heat protection, PLC.
04 Preliminary inspection in the showroom
Preliminary inspection in the Zeilhofer showroom or via video. Safety check, functional test, final adjustments.
02 Concept and specifications
Design, load capacity, heat-resistant mountings and safety features. Binding price indication, free of charge.
04 Manufacturing in Germany
Heat-resistant materials, welded construction, heat-resistant paint, assembly, factory acceptance testing with dummy.
04 Commissioning and training
Our own service technicians travel worldwide, integrate the system into the plant control system and train the staff.
CHAPTER 7
References: 25 years of custom solutions
More than two and a half decades of experience in the metal industry make Zeilhofer HHT a proven partner for hardening plants and heat treaters in Germany and Europe.
What distinguishes Zeilhofer solutions?
-
ISO 9001 certified quality management
-
TISAX Level 2 with prototype protection for confidential customer projects
-
Heat-resistant components for oven removal in the standard range
-
Non-oscillating lifting axes with a load capacity of up to 1,200 kg
-
Engineering and service from Holzkirchen, no outsourcing chains
FAQ / Q&A
FREQUENTLY ASKED QUESTIONS
01 How heavy are the charging racks in the hardening shop?
Empty: 30 to 150 kg. Fully loaded, charging racks and annealing baskets reach 300 to 800 kg, and in large chamber furnaces over 1,000 kg. The ZH90 lifting axis loads up to 1,200 kg without pendulum action.
02 How hot can a sample be when removed from the hardening furnace?
Standard grippers up to 80 °C. High-temperature supports made of aramid or silicate are used for furnace removal (200 to 400 °C), special stainless steel holders for batches above 500 °C.
03 Can a lifting aid prevent distortion of the workpieces?
Yes. Pendulum-free, low-vibration handling prevents slippage in the rack and ensures a uniform position in the oven. This reduces warping and uneven hardening results.
04 Is a lifting axis suitable for the path between the furnace and the quenching bath?
Yes. For time-critical transfers, short, oscillation-free travel distances are crucial. A lifting axis or a jointed manipulator with a heat-resistant mount guides the batch quickly and smoothly.
05 What maintenance is required for lifting aids in the hardening shop?
Annual safety inspections according to DGUV Regulation 54 are mandatory. Due to heat and salt or oil mist, Zeilhofer recommends a visual and functional inspection every six months. Heat-resistant hoses are replaced every 24 to 36 months.
06 Are protective gas and vacuum furnace systems also serviced?
Yes. Zeilhofer supplies charging solutions for chamber furnaces, pusher furnaces, vacuum and protective gas systems. The lifting aid handles the charging racks before and after the furnace.
READ MORE
FURTHER GUIDES ON THIS TOPIC
In-depth guides on related topics in handling technology.
ECONOMY
Increase throughput without adding staff
SAFETY & QUALITY
Handle hot workpieces safely
PRODUCT
ZH90 lifting axle in use
NEXT STEP
YOUR INDIVIDUAL HARDENING SPECIAL SOLUTION
Talk to our engineers about your loading and handling requirements. We analyze batches, temperatures, cycle times, and furnace interfaces and develop a custom machine that fits perfectly. Made in Germany, ISO 9001 and TISAX Level 2 certified, free consultation.