How to Choose Used Hydraulic Shears for Metal
Choosing used hydraulic shears for metal is a strategic decision that impacts production efficiency and operational costs. To make an informed decision, you should carefully assess the technical parameters, machine condition, and safety aspects. This will help you avoid costly mistakes and ensure long-term equipment operation. The optimal choice translates into a competitive advantage.
Introduction to Hydraulic Shears: Types and Applications
Hydraulic shears are a fundamental tool in many industries, from small workshops to large manufacturing plants. They are used for precise and efficient cutting of metal sheets, profiles, and bars. Their operation is based on using hydraulic pressure to generate cutting force, which ensures stability and repeatability of operations. Various types of shears are available, tailored to specific production needs.
Hydraulic Guillotine Shears
Guillotine shears, often referred to as sheet metal shears, are designed for cutting sheet metal of large width and thickness. They are characterized by a simple design and high cutting precision in the production of flat elements. Models such as the Sahinler HKM 115 offer a pressing force of 115 tons, enabling the cutting of large materials. They require regular inspection of the blades and hydraulic system to maintain optimal performance and lifespan. Their design allows for straight and smooth cutting edges, which is important in many applications, such as in the furniture or construction industries.
Hydraulic Universal Shears (Ironworker)
Universal shears, also known as Ironworkers, are multifunctional machines that, in addition to cutting sheet metal, also allow for punching holes, cutting angle profiles, round and square bars, and notching. They are a versatile solution for workshops and manufacturing plants where operational flexibility is required. An example is the Mubea PROFI 500 or Peddinghaus Hydraulic 800 / Peddiworker 800, which integrate several functions into one machine. These machines often have multiple workstations, which increases their productivity and shortens processing time. Their ability to perform a variety of tasks makes them valuable in small and medium-sized enterprises that need equipment for multiple operations but do not have the space or budget to purchase several specialized machines. Integrated functions allow for processing many types of materials without having to reposition elements.
Applications of Hydraulic Shears
Hydraulic shears are used in many industries, including:
- Automotive industry: for the production of body and structural components, where precision and repeatability of cutting are crucial for assembly.
- Construction: for cutting steel profiles, reinforcing bars, and structural sheets, both on construction sites and in prefabrication workshops.
- Machine manufacturing: for the production of machine and equipment components, requiring precise dimensions and smooth edges.
- Locksmithing and metalworking: in the daily work of workshops, where precise cutting is essential for creating custom elements and structures. Guillotine shears used in this industry often handle various types of alloys and material thicknesses, from mild steel to stainless steel. They provide high-quality cutting, which is important for further processing stages, such as welding or bending.
Technical Parameters When Choosing Used Shears
When choosing used hydraulic shears, focus on several technical parameters that determine their suitability for specific applications. Ignoring these aspects leads to purchasing a machine that is not suited to your needs, resulting in financial and operational losses. Proper assessment of these parameters allows for optimal use of the budget and ensures a long equipment lifespan.
Maximum Cutting Thickness and Width
This is a basic parameter that determines the machine's ability to cut materials of specific dimensions. Before buying, carefully check what thicknesses and widths of sheets you will be processing. Guillotine shears can cut sheets with a thickness from 0.02 inches to even 1 inch and widths from 40 inches to 240 inches. Universal shears, such as the Peddinghaus Hydraulic 800, often have limitations on the width of sheet cutting but offer greater versatility in cutting profiles. Always verify these values with the machine's technical documentation and compare them with your own production needs. Remember that the parameters given for mild steel may be different for stainless steel or aluminum. For example, cutting stainless steel often requires 20-30% more force or a smaller material thickness.
Pressing Force
Pressing force, expressed in tons, is fundamental for the efficiency of cutting thick materials. Machines with greater pressing force, such as the Sahinler HKM 115 (115 tons), are able to process harder and thicker metals. Always make sure that the machine's pressing force is sufficient for the materials you intend to process. Insufficient force leads to machine damage and low cutting quality, which generates additional costs. For steel with a tensile strength of 400 MPa, cutting a sheet with a thickness of 0.4 inches over a length of 120 inches requires a force of about 100 tons. Always add a safety margin, at least 10-20% of power reserve.
Blade Length
The blade length directly affects the maximum width of the sheet being cut. Standard blade lengths range from 40 inches to 160 inches. Choose a blade length that corresponds to the largest sheets you will be cutting. Too short a blade limits production capabilities. A longer blade allows for cutting larger elements but may involve higher energy consumption and higher operating costs. The optimal choice is a blade with a length corresponding to 80-90% of the maximum width of the sheets being cut.
Control System
Modern hydraulic shears are equipped with CNC control systems, which increase the precision and automation of the process. Older models may have manual or simple numerical control. When evaluating the control system, pay attention to its intuitiveness, the availability of spare parts, and the ability to program various cutting sequences. The Mitsubishi PLC control in bending machines such as the DW-75 NCBL is an example of an advanced solution that may also be present in some shear models. Check if the software is up to date and if there are possibilities for its expansion.
Example Parameters of Hydraulic Shears
| Technical Parameter | Guillotine Shears (example) | Universal Shears (example) |
|---|---|---|
| Max. cutting thickness | 0.4 inches (mild steel) | 0.6 inches (sheet), 1.2 inches (bar) |
| Max. cutting width | 120 inches | 20 inches (sheet), 8 inches (profile) |
| Pressing force | 100 tons | 80 tons |
| Blade length | 124 inches | None (various tools) |
| Control type | CNC with touchscreen | Manual / Simple CNC |
What to Look for When Inspecting Used Hydraulic Shears
Buying used hydraulic shears for metal requires a detailed inspection. A visual assessment is not enough; it is necessary to check the machine's operation under load and verify the documentation. Below is a checklist to help you conduct a reliable assessment.
Condition of the Hydraulic System
The hydraulic system is the heart of the machine. Look for oil leaks around the cylinders, hoses, and pump. Check the level and quality of the hydraulic oil – dark, foamy oil indicates service neglect or overheating. Start the machine and listen to the pump's operation – unusual noises indicate worn bearings or damaged pump components. The pressure in the system should be stable and consistent with the manufacturer's data. Low, unstable pressure indicates problems with the pump or valves.
Condition of Blades and Cutting Mechanism
The blades must be sharp and free of chips. Dull or damaged blades lead to low cutting quality, excessive energy consumption, and machine stress. Check if the blades are properly adjusted (clearance between the blades) – incorrect adjustment results in material seizing and edge damage. The clearance adjustment mechanism should work smoothly. Also, check the condition of the hold-down beam, which is responsible for stabilizing the sheet during cutting; its damage can lead to imprecise cuts.
Verification of Frame and Structure
The machine frame should be stable and free of cracks, especially in the areas of welds and cylinder mounting. Cracks indicate machine overload or material defects. Check if the machine is level and if there are any visible deformations. Wear of the cutting beam guides manifests as looseness, which affects cutting precision. Excessive vibration during operation is a sign of structural problems or imbalance of moving parts.
Control System and Electrical System
Test all functions of the control system, including emergency stop. Check if all buttons, switches, and screens work correctly. Inspect the electrical cabinet for damage, overheating of wires, or makeshift repairs. Older machines may have outdated control systems, the servicing of which is costly or impossible due to the lack of spare parts. Make sure that all electrical protections are in place and working.
Safety of Using Hydraulic Shears
Safety when working with hydraulic shears is a priority. Used machines often have outdated or damaged safety systems, which creates a risk of accidents. Modernizing these systems is necessary.
Guards and Protective Barriers
The machine should be equipped with complete guards for moving parts, such as the cutting zone, clamping mechanism, and drive components. Light barriers or safety curtains provide additional protection, detecting the presence of the operator in the hazard zone and immediately stopping the machine. Check their operation. The absence or damage of guards requires immediate intervention.
Emergency Stop Buttons
Hydraulic shears must have easily accessible emergency stop buttons (safety mushrooms) in several places around the machine. Test each of them to make sure they immediately stop the machine's operation. Their absence or malfunction disqualifies the machine from use without prior repair.
Safety Markings and Instructions
The machine should have clear safety markings, warnings about risks, and operating instructions in English. The lack of instructions hinders proper operation and servicing. In the case of machines from outside the EU, a CE declaration of conformity is required, confirming compliance with European safety standards. Without proper documentation and certificates, the machine may not meet legal requirements.
Where to Buy and How to Negotiate the Price of Used Hydraulic Shears
Buying used hydraulic shears is an investment that requires a proper approach to supplier selection and price negotiation. The secondary market offers many opportunities but also pitfalls.
Sources of Purchase
- Specialized advertising portals: Platforms like WeSellMachines.com offer a wide selection of used industrial machines, including hydraulic shears. The advantage is a large database of offers and the ability to compare different models. You can find here, for example, the Sahinler HKM 115 in good condition.
- Used machine distributors: Companies specializing in the sale of used equipment often offer machines after inspection and with a warranty, which increases the security of the purchase. They also provide service support and access to spare parts.
- Industrial auctions: They may offer attractive prices, but the risk of buying a machine in poor condition is higher. This requires thorough technical knowledge and the ability to conduct a thorough inspection before bidding.
- Directly from manufacturing plants: Buying from a company that is replacing its machinery allows you to obtain a detailed service history of the machine and usually a lower price. However, it requires more time for searching.
Negotiation Strategies
- Gather information: Before you start negotiations, gather as much data as possible about similar models on the secondary market, their prices, and technical condition. This knowledge is a strong argument in discussions.
- Point out defects: During the inspection, carefully note all defects, worn parts, or missing equipment. Each defect is an argument for lowering the price. Present specific estimated repair costs.
- Ask about the service history: A machine with a documented history of regular inspections and repairs is worth more. The lack of such documentation gives room for negotiation.
- Propose your own price: Never accept the first price. Always propose an amount lower by 15-20% than expected, leaving yourself room for concessions. Used metalworking machines, such as shears, often have flexible prices.
- Consider additional benefits: As part of the negotiation, you can ask for additional tools, delivery included in the price, or a longer warranty if the seller is a distributor.
Operating and Servicing Costs of Used Shears
Buying used hydraulic shears is just the beginning. You need to consider the ongoing operating and servicing costs, which significantly affect the total cost of ownership. Neglecting these aspects leads to costly downtime and shortened machine life.
Blade Wear
The shear blades are a consumable item that wears out. Their regular sharpening or replacement is necessary to maintain cutting quality. The cost of a set of blades for a guillotine with a length of 120 inches ranges from $750 to $2,000, depending on the material and manufacturer. The frequency of replacement depends on the intensity of work and the type of material being cut. Blades for stainless steel are more expensive and require more frequent servicing.
Hydraulic Oils and Filters
Hydraulic oil should be changed every 2000-4000 hours of operation or every 1-2 years, depending on the manufacturer's recommendations. The cost of 50 gallons of hydraulic oil is approximately $375-$625. Hydraulic filters require regular replacement (every 500-1000 hours of operation), and their cost is $25-$75 per piece. Regular replacement of oil and filters protects the hydraulic system from contamination and extends its life.
Service and Repairs
Even a well-maintained machine requires periodic inspections and possible repairs. The cost of an hour of a service technician's work is $37.5-$75. The availability of spare parts for older models may be limited, which increases costs and extends repair time. Remember about regular preventive inspections, which can prevent serious failures. In the case of machines with a TÜV/GS certificate, you can be sure that they meet safety standards, which translates into a lower risk of failure.
Summary and Recommendations
Choosing used hydraulic shears for metal requires a thorough analysis of technical parameters, machine condition, and operating costs. Safety and compliance with production needs are a priority. Remember to conduct a thorough inspection, verify documentation, and negotiate skillfully. Investing in well-chosen used hydraulic shears, such as the Sahinler HKM 115, pays off in the form of increased efficiency and lower production costs. The average savings on the purchase of used shears compared to new ones is about 40-60%, which makes them an attractive option for many enterprises.