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Factory Sale Square expanding stem casters



Product Name:Factory Sale Square expanding stem casters

Square expanding stem casters
Material: PP core with TPR wheel
Size:Ø75 x 22mm ; Ø100 x 30mm
Load Capacity:45kg,60kg
Bearing:Ball Bearing

Caster No. Wheel Material Bearing Thread Height Loading
P90ES-3 75 x 22 PP + TPR Ball Bearing 21~30 118 40 kg
P90ES-4 100 x 30 PP + TPR Ball Bearing 21~30 153 60 kg



Today I would like to share some information with you about the expansion stem caster. Expansion stems come in various different sizes and are used to fit up into hallow tubing usually on tables or chairs. Expansion stems can have more versatility compared to using a friction ring caster and a socket with the reason being, one expansion stem can fit tubing within a certain range of sizes and a round expansion stem can fit up into round and square tubing.

An expansion stem caster is a long stem caster that has threading at the top that is then covered with a rubber expansion grip that goes around the stem. The expansion stem consists of 3 parts, the plastic sleeve(spacer), the rubber sleeve(expansion) and the round nut. The nut is the gripping mechanism which allows the rubber sleeve to be compressed thus expanding its diameter to fit into the tubing snugly.

In order to make your expansion stem fit properly, while holding the swivel bearing at the top of the caster, you want to turn the round nut at the top of the stem clockwise. This will start to tighten which will start to compress and expand the rubber sleeve. Continue to tighten the nut until you expand the rubber sleeve enough to have a very snug fit going up into your tubing. Insert the stem all the way up into your tubing. Once the stem is up in your tubing, turn the swivel bearing counter clockwise to further expand the rubber sleeve inside your tubing. If you need to tighten it further and are struggling to do this by hand, with a wrench, you can turn the hex nut under the swivel bearing counter clockwise until your stem is tight enough for your liking.


For applications in which casters need to be installed on tubular legs, expanding stem casters are a great solution. Expanding stem casters have a long threaded stem, onto which a soft rubber bushing is inserted, along with a hard plastic spacer, and special threaded nut. The 3-piece assembly of spacer, bushing, and nut is known as an expanding stem kit. Installed on a threaded stem, you can tighten the nut to compress the rubber bushing, causing it to expand to a larger diameter.


Expanding stem kits for casters come in a range of sizes from ?” diameter to 1-?” diameter. They generally expand from those starting diameters about 1/16″ to 1/8″ in diameter (i.e. a ?” expanding stem will expand to 7/8″).


They are very easy to use and install. First you must make sure to get the closest size kit to the inside diameter of the leg into which they will be installed, without going over size. In the image below, the inside diameter of the tubing was about 15/16″ so we used a 7/8″ diameter expanding stem kit.


Next, we just tighten the top nut on the stem, compressing and expanding the rubber bushing until it fits snugly into the tubing.


Once the caster has been completely inserted, the last step is to add about a half turn to the hex nut located on the underside of the swivel raceway. If the rubber bushing was snug already, then it should actually grip the inside of the leg enough to where turning this hex head will expanding the stem just a little more.

Expanding stem casters will work on both round and square tubing, making them an suitable solution for many applications. They are available with wheel sizes ranging from 3″ diameter to 6″ diameter and have a variety of brake and total lock options as well.

Popular applications include stainless steel industrial kitchen tables and other commercial kitchen equipment, wire shelving and carts, and custom built tables.


What are expanding stem casters?
Expansion stem casters are designed to mount casters into open tubing fixtures. Turning of hex nut beneath the lower raceway on the caster expands the rubber adapter inside of the round or square tubing for a tight fit.

How do you attach casters to square metal legs?
Image result for Square expanding stem casters
For easy installation, simply drill the hole into your table leg, apply the threaded insert, and screw in your caster. If you opt for a metal table leg, we can apply/install the threaded insert for you, so all you have to do is apply your caster when it arrives.

How are stem casters measured?
Image result for Square expanding stem casters
Measuring the length is a little simpler. Use your ruler to measure the length of the stem from the top of the flared base to the tip of the stem. The caster stem on the right is 7/8″ long.

How do you find the diameter of a stem?
Measure the circumference of the tree (photo) in order to calculate the diameter. Large plants and trees: To measure the diameter of a large plant we measure the circumference of the stem or trunk. The circumference is then converted to diameter (Figure 2).

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