Common Hydraulic Cylinder Sizes
Charlesetta Blare
Ordering the wrong type of hydraulic cylinder can work out expensive. This is easier to do than it might appear, as many product numbers are similar and some suppliers are unwilling or unable to provide the bespoke advice needed to place the correct order.
Our advice team are all experienced hydraulic engineers and can help you get the right size first time. In the meantime, this quick guide will help you avoid common mistakes and make the order process easier.
Mathematically, the area of a circular piston can be calculated by, where A is area and r is the radius. From an engineering perspective, however, it is difficult to calculate the radius directly. We therefore take the diameter (D) and divide it by two.
To calculate maximum possible lift you need to know the pressure input from your hydraulic pump in psi. If this was 1000 psi, for instance, the maximum lift of your hydraulic cylinder would be 7700 lb.
Ordering the wrong size of hydraulic cylinder can have negative ramifications for your application. Get it right first time with our personalised product ordering advice service. As a well-established manufacturer and supplier of hydraulic cylinders, we can ensure you get the right specs for your project each time. Call 01299 896953 for more details.
Honed surfaces, geometrical accuracy, long service life. Although the mounting dimensions and accessory options are according to applicable standards, these series convince through their inner Hnchen values.
There are a number of standards for hydraulic cylinders: The dimensioning standards are intended to guarantee exchangeability between the products of different manufacturers. For round-head cylinders, the following standards apply: DIN ISO 6020-1, DIN ISO 6022. The equipment for standard hydraulic cylinders, such as spherical rod eyes, comes under DIN ISO 8132.
For all those who are obliged to use hydraulic cylinders with mounting dimensions according to ISO 6020-1: our series matches the standard dimensions. With all the benefits you've come to expect from Hnchen.
Cylinders with mounting dimensions according to ISO 6022 with even more Hnchen advantages. We elongate the piston rod to adapt Hnchen cylinders of the series 300 to the standard dimensions.
The result:
Tie Rod, Mill Duty, and Welded are all piston-rod cylinders. They have a piston inside and a rod that extends and retracts through the end of the cylinder. These cylinders can be single or double-acting.
A single-acting hydraulic cylinder includes one port where the hydraulic fluid enters and forces the plunger out in one direction. Force must be applied for the cylinder to retract. This force can come in the form of an internal spring or an external force.
A double-acting cylinder consists of two ports: one for the hydraulic fluid to enter and extend the plunger, and another port for retracting the cylinder. Unlike single-acting, a double-acting cylinder uses hydraulic fluid pressure to retract.
To identify a single vs. double-acting cylinder, there is one common external feature to look for. A single-acting cylinder has a single hydraulic port and hose attached, whereas a double-acting contains two ports and has two hydraulic hoses connected to it.
Another feature to look for is a single rod vs. a double rod. A single-rod cylinder has one rod that extends and retracts out of one end of the cylinder. A double-rod simply has another rod that extends and retracts out of the other end of the cylinder, where both rods are connected to the piston.
First, gather the proper tools and safety equipment required to quickly and safely record the measurements of your cylinder. Safety Equipment should include both eye protection and steel-toe footwear. Tools should include the following:
However, sometimes nameplate information or the cylinder part number may be unavailable or untraceable. In that case, forgo checking for this information and continue on to the next step in measuring and replacing an existing hydraulic cylinder.
The piston diameter is the inside barrel diameter. Also known as the bore diameter, this diameter is the primary dimension of a hydraulic cylinder. If the cylinder is disassembled, measure either the inside diameter of the cylinder tubing or the actual piston diameter. If the cylinder is still assembled or installed, the bore diameter can be measured by using the outside diameter of the cylinder and subtracting the thickness of both tubing walls.
The next step is to measure the hydraulic cylinder rod diameter. The rod is one of the most critical parts of a cylinder because it transfers all necessary force during operation. Because of this, proper measurement of the rod diameter is crucial, as it helps prevent future rod bending.
You may have to apply hydraulic pressure to the cylinder to extend the rod fully. Use necessary precautions when doing so, since atomized spray or mist of oil droplets may extend as far as 40 feet. The flammable oil spray can be ignited readily by hot surfaces and create a flash fire.
First, extend the rod to its maximum extended position. Again, use a tape measure to find the distance between the same fixed point on the cylinder and the marked point on the rod. In the image shown we measured 13.25 inches from the rod wiper to the end of the masking tape.
There are several methods for mounting a hydraulic cylinder. The original equipment manufacturers (OEM) vary how their cylinders are mounted. The standard mounting for industrial cylinders would be the Flange Mount, and the standard mounting for mobile equipment would be the Pivot Mount.
The NFPA publishes standard mounting types, allowing manufacturers to use this visual matrix to help you identify the mounting style on NFPA Tie Rod Cylinders. For further help, download the NFPA Tie Rod Cylinder Mounting Types matrix.
Next, evaluate your existing hydraulic hose ports. The hose port is where the hydraulic lines connect to the cylinder. Without the hoses attached, your cylinder will not work. Each hose has two crimped ends with either male or female ends. The most common design features female ports on the cylinder and requires male hose crimps to be connected.
If the cylinder that you have chosen is different from the thread of the hose, then an adapter can be utilized to make the correct connection. The port sizes shown above are a few of the options available for cylinders. Additionally, the OEM can have custom ports designed into the cylinder. Remember: always check the size closely.
To measure the hydraulic cylinder ports, use a thread gauge and caliper to determine the thread pitch and size. You can also use known fitting to determine thread type and size as an alternative method. Using a thread gauge to determine pitch is illustrated below.
External factors such as working temperature, dust contact, and corrosive materials should always be noted when measuring a hydraulic cylinder. Knowing these factors is vital for selecting the correct materials, wipers, and seals for your hydraulic cylinder.
There are various hydraulic cylinder calculation formulas that you can use to make your life easier. Just plug in the variables to determine the values you require. Here are some of the most useful definitions to keep in mind.
Yates Industries manufactures and rebuilds all types of hydraulic cylinders. We have proudly offered the highest quality products at world-class prices for more than five decades. If you need to replace your hydraulic cylinder or need help selecting the right one, reach out to our team today.
Hydraulic Cylinders, Inc. can help. We offer answers to your frequently asked questions as well as free worksheets to record, guide, and submit your hydraulic cylinder measurements. Contact us for more information or with further questions about how to measure a hydraulic cylinder.
As with base and rod mount dimensions, measuring your hose ports will depend on the style and configuration of your cylinder. The most common design features threaded female ports in the cylinder that require a male hose. Thread sizes generally measure 1/4, 3/8, 1/2, or 3/4 inches. Consult your equipment manual for more information on measuring your hose port size.
If you need more assistance learning how to measure a hydraulic cylinder or identifying which replacement cylinder is right for your machinery, call Hydraulic Cylinders, Inc. at 888-771-1894. We can walk you through the measurement process and help determine which replacement cylinder type is best suited to your needs.
Capacity. Most industrial hydraulics are considered medium-duty and operate at 1,000 psi. Heavy-duty hydraulics, which are common in presses and automotive machinery applications, can handle pressures up to 3,000 psi. If loads are extremely high, tandem cylinders are preferred to larger-bore or custom high-pressure cylinder designs.
Stroking distance. Stroke distances can exceed 10 ft (5.05 m) for custom-built cylinders, but pressure ratings can be a problem with such long strokes. The rod diameter needs to be determined in order to gauge its ability to handle the load. If necessary, a pressure rating on load in thrust (push mode) must be specified. In horizontal applications, which are common, premature rod bearing wear can lead to rod sag over long strokes. Although custom stroke distances above 10 ft (3.05 m) are possible, pressure rating can be a concern.
Several standardized mounts within these styles give engineers alternatives for meeting application requirements. NFPA tie-rod cylinders, for example, are used in most industrial hydraulics and are typically mounted using trunnion-style heads and extended tie rod caps and/or head end styles; flange-style heads; side-lug and side-tapped styles; spherical bearings; and cap-fixed clevis designs. Most mounting options are available for single-acting and double-rod cylinders.
The purpose of the mount is to absorb forces, stabilize the cylinder and improve performance. For rods loaded primarily in compression (push), cap-end mounts are recommended. For those in tension (pull), head-end mounts are preferred. The amount of tension or compression determines piston rod diameter. The amount of pull or push determines the bore diameter.