Balancing Your Investment in Hydraulic Spare Parts
Maintaining a well-functioning hydraulic system is all about preparation. Deciding which spare parts to stock depends on the criticality of your system. While some replacement parts are readily available, others may have longer lead times or limited availability, which can delay repairs. Preparing wisely by assessing your system’s needs will help you stay ahead.
Here’s a helpful guide to common hydraulic system failures and which essential parts to keep on hand to keep your operations running smoothly.
Hydraulic Leaks
Hydraulic system leaks often stem from worn seals, damaged hoses, cracked fittings, or loose connections. Look for visible fluid, reduced performance, unusual noises (hissing or whining), or decreased hydraulic pressure. Internal leaks, detected through hot spots, can be located using a heat gun or laser thermometer if a thermal camera is unavailable.
It’s a good idea to keep the following spare parts on hand as they are inexpensive and common wear items:
- Assorted O-rings (Buna-N, Viton)
- Seal kits
- Be sure you have a source to obtain:
- Hydraulic hoses
- Tube fittings
- Thread sealant
- Pump Problems
Common pump problems include cavitation, caused by air pockets due to low inlet pressure or restrictions, or aeration, air mixed with fluid, which causes noise, foaming, and component wear. Worn or damaged pump components may reduce pressure and flow output, resulting in possible system failure.
This can be easily fixed by keeping pump shaft seals and suction filters in stock. Depending on the criticality of your hydraulic system, having a spare pump on hand may also be wise. If the system can be down for a few days until one is obtained, you may not need one on the shelf, but you should know where to get one.
Overheating of Hydraulic Fluid
Overheating of hydraulic fluid can be caused by a blocked cooler, incorrect fluid, or continuous high-pressure use. Overheating can lead to pump failure.Be sure to keep the correct hydraulic fluid for your system on hand. Depending on how critical the machine is, you may also want to keep a replacement cooler fan or heat exchanger unit along with temperature sensors on hand.
Slow or Jerky Operation
Air in the system, sticky valves, low fluid, and contamination can cause a system to move slowly or not move at all. To address this issue quickly, keep hydraulic fluid filters (inline, return, and suction filters) on hand. While it is not necessary to keep in stock, have a source to quickly obtain directional control valves, pressure relief valves, and flow control valves.
Pressure Loss
Pressure loss can result from several issues, including internal leakage, cracked lines, or a faulty pressure relief valve. When pressure decreases, the system loses strength, which can significantly impact functionality. For instance, in a tool changer arm, pressure loss may cause it to operate sluggishly, move with a jerky motion, or fail to move altogether. It’s a wise idea to stock one backup accumulator (if used in your system) as it can be a longer lead item. Be sure to know where to obtain pressure gauges, pressure relief valves, cylinder seal kits, and hydraulic lines and hoses.
Contamination in the Fluid
Possible causes of contamination can be operating in a dirty environment, poor maintenance, and failing system components. Contaminated hydraulic fluid can lead to performance issues and potential system failures. A contaminated system may also require replacing the filter breather. Affordable items to keep on hand include hydraulic filters (return, suction, pressure-side) and filter elements. You may also want to have access to desiccant breathers.
Cylinder Failure
A cylinder failure can occur due to various reasons, including seal wear, bent rods, or internal scoring. The key indicator of the problem is heat, which could result from either internal or external leakage. To diagnose the issue, check the cylinder for any noticeable heat by using a laser thermometer (an essential diagnostic tool) to measure the surface temperature accurately. This will help pinpoint the cause of the failure and guide further action. You will want to stock spare hydraulic cylinder seal kits, rod wipers, and spare cylinders, if you cannot afford machine downtime.
Valve Failure
Valve failures can present various challenges in system performance. Common issues include sticking or binding valves, often caused by contamination or mechanical wear, which can hinder their proper functioning. Solenoid coil failure is another concern, as electrical issues can prevent proper actuation. Additionally, incorrect valve settings, such as improper pressure, flow, or direction, can damage components or lead to poor system performance. Be sure to stock valve gaskets and valve body seals, and have a source to quickly obtain solenoid coils, and replacement valves or cartridge valves.
Accumulator Issues
Accumulator issues can be caused by a recharge loss or bladder rupture. It’s important to keep gas charge kits (nitrogen bottle, regulator, gauge) on hand for repairs.
Electrical/Control Issues for Electrohydraulic Systems
Electrical/Control Issues can be caused by faulty wiring, sensor failures, and bad relays. Be sure to keep pressure switches, proximity sensors, fuses, and relays in stock, and PLC input/output cards, if applicable. General and regular preventative maintenance is a good way to check the condition of these types of devices.
Stay Prepared and Minimize Downtime
Understanding common hydraulic failures and being equipped with the right spare parts can save valuable time and prevent costly downtime. By stocking essential components and building relationships with reliable suppliers for quick access to critical parts, you’ll ensure continuous and efficient operations. With more than 30,000 parts in stock, competitive prices, and same-day shipping, All World Machinery Supply is a critical supplier for maintaining your operations.
If you’re ready to optimize your spare parts management or need further guidance on your hydraulic system, get in touch with us or explore our spare parts inventory today.
