The sprocket must be selected taking into consideration the model number and specifications of the chain to be used.

The basic steps are as follows:

1. ① Chain size and model number selection
2. ② Check the chain roller type
3. ③ Check the number of teeth (speed ratio and space)
4. ④Whether or not the tooth tip is hardened (quenched)
5. ⑤Check the required shaft hole based on the shaft design
6. ⑥Hub type
7. ⑦ Check the hub diameter, maximum shaft hole diameter, hub length, key surface pressure, etc. (strength, space)
8. ⑧ Decide on the sprocket model number

Standard sprockets are designed with strength balance and economy in mind, but we can also manufacture sprockets to the dimensions required by the customer, with quotes and made-to-order production.

Material	Uses and Features
General structural rolled steel	When strength or hardness is not required, it is used for some sprocket without teeth hardened or hub material for weld. Teeth hardening treatment is not possible.
Carbon steel for machine structures	Widely used in general-purpose sprockets. Hardening the tooth tips increases wear resistance and strength.
stainless steel	Used for corrosion resistant sprockets. It has high corrosion resistance, but its metal strength is inferior to that of carbon steel.
resin	Used for corrosion resistant sprockets. It has high corrosion resistance and is lightweight, but its weakness is low strength and vulnerability to heat.

Please refer to the table below for a list of materials used for stainless steel sprockets.

The stainless steel sprockets listed in the catalogue are made of austenitic stainless steel (SUS304 series), and due to the characteristics of the material, tooth tip hardening treatment (quenching) cannot be performed.

If you require tooth tip hardening treatment using stainless steel, we can manufacture it using martensitic stainless steel (SUS420 series). (Quote required/Made to order)

We also offer sprockets that are surface-treated to increase hardness and are recommended for use with high-strength stainless steel chains. (Quotes available, made-to-order products)

Please contact us if you have any requests.

We recommend using the same material. Our lineup of stainless steel sprockets is designed to be used in combination with stainless steel chains.

For example, using a stainless steel chain in combination with a plated steel sprocket can cause potential corrosion (galvanic corrosion) and lead to early wear.

The "tooth tip hardening treatment" described in the catalog is a process that hardens the surface by induction hardening.

The teeth are hardened to improve their wear resistance and strength. Generally, tooth tip hardening is performed when the rotation speed is high (the number of times the chain engages per unit time is high), when there are few teeth and a small winding angle, or when wear inclusions are present.

Generally, carbon steel for mechanical structures is used as the material for tooth tip hardening treatment, but structural alloy steel can also be used upon request.

Since it is a type of quenching treatment, it is also called "with teeth hardened treatment = quenching specifications" and "without teeth hardened treatment = unhardened specifications".

The standard set screw specification for our sprockets is a "hexagon socket set screw (recessed tip)."

Standard sprockets other than Fit Bore and special sprockets (estimated or made to order) are not included as a general rule.

Stainless steel set screws are included for products with a stainless steel or plated body.

1. ①RS sprockets for Drive chain and double-Double pitch sprockets for Small size conveyor chain are classified by hub shape into A-type (flat type), B-type (single hub type), C-type (double hub type), and SD-type (single dual = two single strand chains) (Figure 1).
2. ②Sprockets for Large size conveyor chain are classified into four types based on welded specifications (Figure 2).

   Type B (single hub) and type C (double hub) have the welding symbol W. Those with the symbol 1 have the hub welded through the toothed section.

When welding hubs to A-type sprockets, the heat from the welding may make it impossible to maintain quality.

Please refrain from welding by yourself and consult with us.

We do not recommend additional work by the customer as this may result in damage or other accidents.

A pilot bore is a hole that is necessary during the process of manufacturing a sprocket, and are generally not drilled to the tolerances appropriate for shaft assembly.

We can manufacture with appropriate tolerances within the range of +1mm or more from pilot bore to the maximum shaft hole diameter.

The standard pilot bore type shaft hole is machined so that the diameter is less than the "maximum shaft hole diameter" in the dimension table listed for each model number and number of teeth in the catalog.

For A-type sprockets that do not have a maximum bore diameter listed, please contact us and we will consider manufacturing them.

Unless otherwise specified, the keyway will be machined in the position shown below.

"Fit Bore" means a "sprocket with a completed shaft hole."

"Fit" means to fit, and "bore" means to drill a hole. You select the specifications from the service range listed in the catalog, and we will process the shaft hole (shaft hole processing, keyway processing, tap hole processing) and deliver it to you in a state that you can use immediately.

We offer "stock items with shaft holes already machined to our specifications" and "made-to-order items where shaft holes are machined to the specifications selected by the customer."

You can choose from over 100 million options for shaft hole processing specifications in the TT-net Drawing Library.

Click here to select processing details and output drawings

We may decline your request depending on the specifications and conditions, but we will consider whether or not it can be manufactured. Please contact us.

Lock Sprocket are friction fastened sprockets that fasten the sprocket to the shaft without using a key, and have the following features:

1. ①No backlash after fastening (fastening without backlash)
2. ②Easy phase alignment
3. 3. Easy to install and remove
4. ④No need for retainers as there is no axial movement

Lock Sprocket are not available in inch sizes.

Tsubaki Power-Lock are available in inch sizes, so we recommend using Power-Lock.

It can be used on any shaft with a standard keyway shape.

However, please note that the allowable transmission torque will be reduced by approximately 10%.

This is because the contact area between the lock sleeve and the shaft is reduced by the size of the key groove.

Similarly, when using a Tsubaki Power-Lock, the allowable transmission torque will be reduced.
(However, the EL series cannot be used on shafts with keyways.)

Any series other than the EL series can be used as long as the shaft has a standard keyway shape.

However, please note that the allowable transmission torque will be reduced by approximately 10%.

This is because the contact area between Power-Lock and the shaft is reduced by the size of the key groove.

Similarly, the allowable transmission torque will be reduced when Lock Sprocket is used.

Depending on the surface treatment required, we can provide estimates or make to order.

Stainless steel Lock Sprocket are not available.

Generally, the inner diameter of the shaft hole is not plated.
The inner diameter of the shaft hole is also treated with black oxide.

We do not recommend that customers perform surface treatments on products after purchase, as this may result in a decrease in strength or other issues.

We are unable to determine the specifications for dimensions and breaking strength. If you are unable to provide detailed requirements, unfortunately we will have to decline your order due to quality assurance issues.

All of our sprockets comply with the RoHS Directive. If you require a certificate, please request one through the retailer where you purchased the product.

It is not possible to identify an item based on its appearance alone, so specifications cannot be determined from photographs.

We are sorry, but we are unable to accommodate your request.

We can assist you in specifying specifications by requesting a quote.

However, even if we check the actual product, we may not be able to determine the specifications.

Please note that even if we provide you with a quote, we cannot take responsibility for the specifications.

If the item is used, it will no longer retain its original shape, making it difficult to determine the exact dimensions, and if the item is severely damaged, it may not even be possible to determine the general specifications.

In some cases, it may not be possible to identify the materials.

We ask that you make the final decision on specifications by referring to our opinion.

Do not store in dusty or dirty places, in places exposed to direct rain, high temperatures, freezing or corrosive atmospheres.

Please apply oil with a brush to prevent rust.

Please be especially careful with items that are not painted, or even if there is paint, areas such as the shaft holes that are not painted.

Applying grease to the meshing area between the sprocket and chain can be effective at low speeds and high loads.

However, in dusty places, the dust may be attracted and stuck to the surface, which may accelerate wear.

In addition, it is important to oil the spaces between the pins and bushings of the chain to prevent wear and elongation.

Grease is sometimes applied to the chain to prevent the oil from flowing out due to external factors (wind, rain, etc.), but conversely, if the grease prevents oil from reaching the spaces between the chain pins and bushings, the oiling effect may be reduced, so please take this into consideration.

Sprocket wear cannot be determined by its appearance.

Just like chains, sprockets also wear, so please inspect and check for any abnormalities such as wear using the inspection methods described in the catalog or Instruction Manuals before making your decision.

The table below summarizes possible causes and remedies for wear on a sprocket tooth (root, tooth pressing surface).

We offer sprockets equipped with Indicator pins (replacement notification mark) that lets you know at a glance when it's time to replace them.

Standard equipment on Smart Replaceable Series of sprockets (split type, ring replacement tooth type, block replacement tooth type) which require frequent replacement.

The standard sprocket equipped with Indicator pins is identified as being painted in "Tsubaki Blue."

We do not sell directly, so please contact your local distributor or retailer.

Please also contact us regarding delivery.

For Drive chain tooth tip hardening treatment is performed on sprockets that meet the following usage conditions.

1. 1) When the number of teeth is small (24 or less) and the maximum rotation speed is 1/8 or more of the maximum rotation speed listed in the catalog kW ratings table.
2. ② Small sprocket when the speed ratio is greater than 4:1.
3. 3) For low speeds and heavy loads (when using Tsubaki RS-HT chain)
4. 4) When used in an environment that may wear down the teeth.

The appropriate operating temperature range for RS sprockets is -10°C to 150°C, while the appropriate operating temperature range for stainless steel RS sprockets is -20°C to 400°C.

Not only do temperature-related changes in strength have to be considered, but also the limitations of chain lubrication.
Please check Drive chain product list in Drive chain & Sprocket Catalog.

The standard sprockets listed in the catalog are made of carbon steel or rolled steel for machine structures, and are not recommended for use in temperatures below -10°C as their strength will decrease.

We may be able to propose countermeasures such as special sprockets made to order using different materials.

Please contact us regarding products with operating temperature ranges not listed in the catalog.

Standard sprockets with hardened teeth can be used, but there are many cases where the key surface pressure is insufficient.

We offer "TOUGH TOOTH" as a recommended sprocket for Heavy duty drive chain, so please consider it.

The stronger the chain, the more important it is to check the key pressure, etc.

Although it is possible to increase the surface pressure by using a double key or lengthening the hub, we recommend the "TOUGH TOOTH" with its stronger hub from the standpoint of space saving and price.

Also, when using H-class chains such as HT Heavy Duty chains and Super-H chains in multiple strands, standard RS sprockets cannot be used because the transverse pitch of the teeth is different.

Cannot be used with JIS standard RS sprockets as the three basic dimensions (pitch, roller diameter, and roller link inner width) are different.

For BS standard chains, we offer BS/DIN standard dedicated sprockets.

We offer standardized tensioners and idlers. Please consider our specifications.

<Rotation irregularities>

Chain speed fluctuations and the properties of the sprocket cause uneven rotation of the driven sprocket.

Furthermore, there are also influences from eccentric mounting errors of the sprocket and manufacturing errors of the chain and sprocket.

Increasing the number of teeth on the drive sprocket (larger diameter) will result in smoother transmission and less rotational irregularities.

The sprocket may also be the cause. The causes and solutions are as follows:

polygon movement

When chordal action (polygonal movement of the sprocket and chain) is involved, polygonal movement can be suppressed by selecting as many teeth as possible. Generally, 15 or more teeth are recommended.

* "Cordal Action": See "Q51. What are the causes and solutions for uneven sprocket rotation?"

Double pitch S rollers cannot be used with RS sprockets with 29 or fewer teeth; Double pitch sprockets are required.

Standard RS sprockets for Drive chain with 30 or more teeth. (This is because the pitch circle diameter (PCD) is an approximate value for sprockets with 30 or more teeth.)

Additionally, sizes larger than RF2060 cannot be used in multiple strand because transverse pitch is different. In this case, it is considered a special-shaped chain, so we will consider manufacturing a special-shaped sprocket based on the chain diagram.

RS sprockets for Drive chain can be used with RS type small conveyor attachment chains.

However, please note that if the sprocket diameter is small or the attachment is special, you will need to consider interference with the sprocket.

For Double pitch, use Double pitch sprockets.

However, if Double pitch S rollers are used and the number of teeth is 30 or more, RS sprockets can be used.

For S rollers, an odd actual number of teeth is recommended as this will increase wear life.

In Double pitch sprockets, the number of teeth that actually mesh is called effective number of teeth, and the number of apparent teeth is called actual number of teeth.

If the chain is an S-roller type, the chain will engage every other tooth (Fig. 1).

When actual number of teeth for an S roller is odd (see Figure 3), the rollers on the first rotation will mesh with numbers 1 to 10, skipping every other tooth, but from the second rotation onwards they will start meshing with number 11, a different tooth from the previous rotation. Because the rollers mesh with different teeth on each rotation of the sprocket, there is less wear and the rollers have a longer lifespan.

In the case of R rollers, each tooth engages (Fig. 2).
For R rollers, the teeth that mesh with each rotation are always the same, so there is no difference in wear or lifespan due to differences in actual number of teeth.

As with standard RF Double pitch, RS sprockets for Drive chain can be used when the number of teeth is 30 or more.

It cannot be used with 29 teeth or less, so Double pitch sprocket is required.
(This is because the pitch circle diameter (PCD) becomes an approximate value when the number of teeth is 30 or more.)

For multiple strand, sizes RF2060 and above cannot be used due to the different transverse pitch. In this case, it is considered a special-shaped chain, so we will consider manufacturing a special sprocket based on the chain diagram.

Considering the chain grip, a minimum of 6 teeth is required.

Yes, but it is a made-to-order product, so please provide us with a quote.

If the part is intended to be welded, this may lead to defects depending on the material.

For products with hanging holes, please check the catalog.

For sprockets with hanging holes, the hanging hole dimensions and number of holes are specified in the hanging hole dimension list in addition to the sprocket body dimension table.

Sprockets with model numbers and tooth counts not listed do not have hanging holes.

If you have any requests, we will consider production and provide a quote on a case-by-case basis, so please let us know the specific location, size, and number.