Q&A  Reducers

The following is a list of answers for frequently asked questions from our customers. Select questions to view the answers.

Worm Gear Reducers

Words 

Technology

Q1 What's the efficiency of worm reducer?
Q2 What's the reduction ratio that can be expected to be self-locking?
Q3 What's the rotational relationship between worm reducer input shaft and output shaft?
Q4 What's the percentage of the worm reducer rotational fluctuation ( Angular velocity fluctuation rate )?

Options

Q5 What's the suitable application for Power-Lock shaft specification?
Q6 What's the difference between low backlash specification and standard type?
Q7 Can the self-locking be expected with double reduction (EW100B600L-R)?
If not, is MTO available?
Q8 The standard oil gauge can be easily viewed from the front. Are there other types good for side view?
Q9 Are Special reduction ratios and left-hand specifications available?

Selection

Q10 What are the necessary conditions for sizing a worm reducer?
Q11 Can worm reducers be driven by hand power?
Q12 When using worm reducer for lifts, is the starting efficiency same as those listed in product catalog?
Q13 We are thinking of replacing other companies products, how to get the reference data?
Q14 We are thinking of replacing old models with the new, how to get the reference data?

Lubrication

Q15 How to clean the housing inside when replacing lubrication oil?
Q16 Is it possible to change into other brands lubrication oil?
Q17 Where to purchase the recommended lubrication oil ( Daphne Alpha Oil TE***)? How many L- units are available?
Q18 Is it possible to fill in food machinery lubrication oil (H1 grade)?

Handling

Q19 Are there any mounting limitations by worm reducer series, type, and size?
Q20 What's the function of pressure valve? Is it mounted when delivery?
Q21 When contacting Tsubaki about replacing the old model worm reducer, is the information of product model number enough?
Answers
Q1 What's the efficiency of worm reducer?
A1

The efficiency varies by the input shaft speed.

For example, the efficiency of EW100T10R (Size 100, Reduction ratio 1/10) is more than 90% at the input speed of 1,750r/m, while the efficiency becomes about 80% at the speed of 100r/m.

The efficiency can be calculated using the catalog listed capacity.

Efficiency graph
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Q2 What's the reduction ratio that can be expected to be self-locking?
A2

In general, series with a reduction ratio of 1/60, 1/50 can be expected to be self-locking from a standstill condition.

Our worm reducer specification is efficiency-oriented and a reduction ratio of 1/60 can be expected to be self-locking.

Self-locking reinforced specification is available, please contact us for details.

For detailed information, please refer to Tsubaki Worm Reducer catalog. (Tsubaki Troi Drive Worm Power Drive)

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Q3 What's the rotational relationship between worm reducer input shaft and output shaft?
A3

The standard worm gears are all right-hand specifications. The rotational relationship is shown as below.

Both clockwise and counterclockwise rotation are possible.


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Q4 What's the percentage of the worm reducer rotational fluctuation ( Angular velocity fluctuation rate )?
A4

Worm power drive (cylindrical worm ) has less rotational fluctuations than other gear reducers, its about 1~2%.

Troi Drive (drum-shape worm) has the most constant rotations among any other gear reducers, and the percentage is about 0.5%.


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Q5 What's the suitable application for Power-Lock shaft specification?
A5

Power-Lock shaft type combines hollow shaft with friction locking device (Tsubaki Power-Lock SL series)

This type is suitable for inertia moment applied applications to avoid key wear-out..

When using for lifts, bad installation may cause falling risk, separate safety device on the driven shaft is recommended.

Power-Lock specifications are available with SW, EW, TD series hollow shaft types. Croise Motor type is also available, please contact us for details

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Q6 What's the difference between low backlash specification and standard type?
A6

Low backlash specification is available with EW, SW, TD series.

Comparing with the standard type, the thrust gap of worm shaft is reduced to cut back on the backlash.
For example, the standard backlash of EW125T20L is 0.06 to 0.36°, but with the low backlash specification, it can be reduced to 0.06~0.14°.

The backlash can be further reduced by remaking reducer case or worm gear. Please contact us for details.

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Q7 Can the self-locking be expected with double reduction (EW100B600L-R)?
If not, is MTO available?
A7

Double reduction ratio of the worm reducer is the combination of 1/20×1/30.
Self-locking can not be expected with this combination.

For MTO, it is possible to change the ratio combination.
For example, self-locking can be expected by changing the combination into 1/10 X 1/60.

Changing ratio combination has little effect on the price and delivery, as all these combinations use standard gears.

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Q8 The standard oil gauge can be easily viewed from the front. Are there other types good for side view?
A8

Standard oil gauge is bulls-eye type, suitable for front view. Clamp and upright types are also available and good for side view.

Clamp oil gauge is attached separately to avoid damages during delivery.

Please remove the blind plug and mount the oil gauge before operation.


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Q9 Are Special reduction ratios and left-hand specifications available?
A9

We have a rich record of special reduction ratios.
But as customized tools are needed, special reduction ratio types are used for continued or large lot products.
Left-hand types are also available, please contact us for details.

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Q10 What are the necessary conditions for sizing a worm reducer?
A10

The sizing of worm reducers is same as other reducers.

Main conditions include ①Application ②Motor capacity and input speed ③Output shaft torque or load torque ④Output shaft speed or reduction ratio
⑤Output shaft shape and arrangement ⑥Output shaft load ⑦Operating hours(per day) ⑧Start / stop frequency (per hour)⑨Ambient temperature.

However, if the moment of inertia is large, special attention needed when using in lifts or turnover devices. Please contact us for details.

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Q11 Can worm reducers be driven by hand power?
A11

Yes, for capacities, please refer to catalog capacity values of 100r/min.

For lifting and turnover applications, please choose reduction ratios that self-locking can be expected. It's recommended to attach a holding brake.

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Q12 When using worm reducer for lifts, is the starting efficiency same as those listed in product catalog?
A12

The transfer capacities listed in the catalog assume the reduce is driving a load rate of 100% in continuous operation and at a constant oil temperature.

Efficiencies will lower during cold starts, please discount the capacity using the ratios given below. The discount rate varies from‐4% to the max of -15%.


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Q13 We are thinking of replacing other companies products, how to get the reference data?
A13

Please access below link, our special site designed to help users find equivalent products from other companies products.
For the ability, appearance, dimensions and other specifications, be sure to confirm details in the product catalog.

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Q14 We are thinking of replacing old models with the new, how to get the reference data?
A14

Please access below link, our special site designed to help users find equivalent products from old model numbers.
If there are any model numbers can't be found, please contact us.

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Q15 How to clean the housing inside when replacing lubrication oil?
A15

Please follow below instructions:

  1. Operate slightly to raise the temperature of lubrication oil, and then evacuate from the drain plug.
  2. Fill in new oil a little and operate a short while.
  3. Drain the oil from 2.
  4. Repeat above two steps for 2 or 3 times until the oil is free from impurities or friction chips.
  5. Fill in right amount of new lubrication oil.

※ High temperature, please follow instruction guide to avoid burn risk.

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Q16 Is it possible to change into other brands lubrication oil?
A16

Lubrication oil is vital to reducer capacity, life and efficiency. Use only lubrication oil recommended by Tsubaki.

Do not mix the oil with other brands.
Please contact us when changing oil brands.

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Q17 Where to purchase the recommended lubrication oil ( Daphne Alpha Oil TE***)? How many L- units are available?
A17

Lubrication oil can be purchased from Tsubaki Chain agencies or Idemitsu.

4L-unit are available at Tsubaki agencies, while Idemitsu provides 20L-unit.

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Q18 Is it possible to fill in food machinery lubrication oil (H1 grade)?
A18

Yes, but the catalog capacity value may drop. Please contact us for details.

This is not our standard Contact us for quotation.

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Q19 Are there any mounting limitations by worm reducer series, type, and size?
A19

Yes, please mount correctly to avoid troubles like bad lubrication or oil leakage.

Please refer to product catalog for mounting limitations.

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Q20 What's the function of pressure valve? Is it mounted when delivery?
A20

The pressure vent is used to let out the pressure inside of the reducer.

If the pressure can't be relieved, lubrication oil may leak from the oil seal.

Pressure valve is attached with the reducer, please mount before operation.

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Q21 When contacting Tsubaki about replacing the old model worm reducer, is the information of product model number enough?
A21

The specification may vary with the same model number. Please forward us all information written on the name plate including

① Model No. ② Reduction ratio ③ Serial No. ④ Drawing No.


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