EFW Electric Torque Multipliers

Mountz EFW Electric Torque Multipliers provide precise, controlled tightening and loosening for heavy-duty fastening applications where a right-angle configuration improves access. Powered by a brushless motor with a built-in microprocessor controller, EFW models provide smooth, continuous, non-impacting rotation and automatically shut off when the preset torque is achieved. Available models cover torque ranges from 118–7,228 lbf.ft (160–9,800 N·m), providing a right-angle alternative to Mountz's inline EF Electric Torque Multipliers.

Quick Answer

EFW Electric Torque Multipliers are right-angle electric torque multipliers designed for precision tightening and loosening of heavy-duty fastening connections. They use a brushless motor and built-in microprocessor controller to provide smooth, continuous, non-impacting rotation and automatically shut off when the preset torque is achieved. Current EFW models cover 663–7,228 lbf.ft (900–9,800 N·m), use a 1 1/2-inch square drive, and provide accuracy better than ±5%.

Who This Is For

Manufacturing and assembly operations requiring high torque
Maintenance technicians
Field service technicians
Wind energy assembly and maintenance
Oil & gas pipeline maintenance
Oil & gas rig maintenance
Heavy-duty assembly operations
Heavy-duty maintenance operations
Applications where a right-angle electric multiplier configuration is appropriate

Mountz specifically identifies electric torque multipliers for heavy-duty assembly and maintenance and cites windmill gearbox assemblies and oil & gas pipeline and rig maintenance as applications.

When Should You Use This?

Use an EFW Electric Torque Multiplier when:

High-torque fastening is required.
A right-angle electric multiplier configuration is appropriate for the application.
AC electrical power is available.
Precision tightening or loosening of heavy-duty fastening connections is required.
Smooth, continuous torque application is preferred.
Automatic shut-off at the preset torque is needed.
Non-impacting operation is preferred.
A built-in controller is preferred over a separate controller box.
The required torque falls within the available EFW model ranges.

Mountz identifies the EFW specifically as its right-angle electric torque multiplier, with a current overall torque range of 663–7,228 lbf.ft.

When Should You NOT Use This?

An EFW Electric Torque Multiplier may not be appropriate when:

Electrical power is unavailable.
The required torque falls outside the available EFW torque ranges.
A suitable reaction point cannot be established.
An inline electric multiplier is more appropriate for the fastening location.
A pneumatic or manual power source is required by the application.
The fastening location requires a different multiplier configuration.

Mountz offers inline electric, pneumatic, hand, and radial gearing torque multipliers for applications requiring other configurations or power sources.

How EFW Electric Torque Multipliers Work

EFW Electric Torque Multipliers use an electric motor and gearing system to apply controlled high torque to threaded fasteners.

During operation:

Install the appropriate socket and reaction device.
Position the socket completely on the fastener.
Position the reaction device against a safe, stable reaction point.
Connect the multiplier to the appropriate power supply.
Select the required torque setting.
Select the direction of rotation.
Activate the multiplier.
The tool applies smooth, continuous rotation.
During tightening, the motor stops when the preset torque is reached.
After fastening, change the torque direction and briefly operate the tool as needed to free the reaction device before removing the tool.

Mountz's operating instructions specify that the socket or connector should be completely engaged, the reaction device should be supported at the same level, and the multiplier should remain properly aligned during fastening.

Result

Precision high-torque fastening
Automatic shut-off at preset torque
Smooth, continuous rotation
Non-impacting operation
Right-angle configuration
Built-in torque control
No separate controller box required

Core Features

Right-angle electric torque multiplier
Accuracy better than ±5%
Automatic shut-off at preset torque
Smooth, continuous, non-impacting rotation
Microprocessor controlled
Built-in controller for speed, frequency, and torque
Brushless motor design
Low-maintenance motor
Overheat protection
Universal AC input: 100–253V / 45–66 Hz
Free-floating or lockable handle
1 1/2-inch square drive on current models
Reaction foot supplied
All-weather models available
Remote-control operation available
Standard models feature an LED display
Plus models feature an LC display

EFW Electric Torque Multiplier Models

The current Mountz website lists four EFW Electric Torque Multiplier models: EFW400, EFW600, EFW800, and EFW1000. All four use a 1 1/2-inch square drive.

Available Models

Model	Item #	American Torque Range	S.I. Torque Range	Square Drive	Speed	Tool Weight	Tool Height
EFW400	210618	663–3,134 lbf.ft	900–4,250 N·m	1 1/2"	8 RPM	35 lbs	12.5 in
EFW600	210619	811–4,536 lbf.ft	1,100–6,150 N·m	1 1/2"	7 RPM	44 lbs	13.7 in
EFW800	210620	1,327–5,752 lbf.ft	1,800–7,800 N·m	1 1/2"	4 RPM	52.5 lbs	13.7 in
EFW1000	210621	1,512–7,228 lbf.ft	2,050–9,800 N·m	1 1/2"	3 RPM	64 lbs	15 in

Model Selection Guide

If you need...	Recommended Model
Lowest available EFW torque range	EFW400
Torque up to 3,134 lbf.ft	EFW400
Torque up to 4,536 lbf.ft	EFW600
Torque up to 5,752 lbf.ft	EFW800
Maximum EFW torque capacity	EFW1000
Highest operating speed	EFW400
Lowest tool weight	EFW400

When selecting an EFW model, consider:

Required fastening torque
Fastener and socket size
Available working space
Required operating speed
Tool weight and height
Reaction point
Operating environment

Select a model whose specified torque range includes the required fastening torque.

Torque Capacity & Operating Speed

Model	Maximum Torque	Operating Speed
EFW400	3,134 lbf.ft	8 RPM
EFW600	4,536 lbf.ft	7 RPM
EFW800	5,752 lbf.ft	4 RPM
EFW1000	7,228 lbf.ft	3 RPM

The EFW400 provides the highest operating speed at 8 RPM, while the EFW1000 provides the highest torque capacity at 7,228 lbf.ft.

Standard & Plus Models

Mountz states that standard models feature an LED display and Plus models feature an LC display.

The operating instructions identify additional functions for the EFW Plus configuration, including torque and angle-based fastening modes. Because these controls differ from the standard EFW, operators should follow the applicable instructions for the specific model and configuration being used.

LED Display & Torque Settings

Standard EFW models use an LED display for torque selection.

The operating instructions describe:

10 primary torque settings
9 intermediate settings
19 total torque stages
Clockwise and counterclockwise operation

The torque value associated with each stage depends on the specific multiplier model. Refer to the appropriate torque chart in the operating instructions when selecting the setting.

Plus Model Operation

EFW Plus models use an LC display and provide additional fastening controls.

The operating instructions describe two modes:

Mode	Function
M1	Tightening with torque, with an option for automatic release by a preset angle
M2	Tightening to preset torque followed by a finishing-angle rotation, with an option for automatic release

The automatic release function is used to release the reaction device after fastening. Follow the EFW Plus operating instructions when configuring torque, angle, and release settings.

Automatic Shut-Off

EFW Electric Torque Multipliers automatically shut off when the preset torque is achieved. They apply torque with smooth, continuous, non-impacting rotation.

This provides:

Controlled final tightening
Automatic stopping at the preset torque
Smooth torque application
Non-impacting operation

Built-In Controller & Brushless Motor

EFW Electric Torque Multipliers feature a microprocessor-controlled system with a built-in controller. Mountz states that speed, frequency, and torque correspond with the built-in controller, so a separate controller box is not required.

The tools also feature a brushless motor design, which Mountz identifies as providing low-maintenance operation.

Overheat Protection

EFW Electric Torque Multipliers include overheat protection.

Follow the operating instructions if the multiplier stops operating or shows signs of a problem during use.

Universal AC Input

EFW Electric Torque Multipliers support:

100–253 VAC
45–66 Hz

Verify the available electrical supply and inspect the power cord and plug before operation.

Right-Angle Configuration

EFW Electric Torque Multipliers use a right-angle configuration, distinguishing them from Mountz EF inline electric torque multipliers.

The right-angle configuration provides another tool orientation for heavy-duty fastening applications. Model selection should account for the available working space and physical dimensions of the multiplier.

Reaction Device

All EFW Electric Torque Multipliers are supplied with a reaction foot.

The reaction device absorbs the rotational force generated during fastening.

For safe operation:

Install the reaction device securely.
Position it against a safe, stable support.
Position the support arm at the same level as the socket or connector.
Keep hands away from the reaction device while the tool is operating.
Make sure the reaction setup remains stable during fastening.

Mountz specifically warns against placing a hand on the reaction device during operation.

Free-Floating & Lockable Handle

The EFW handle can free float or lock in a set position.

The appropriate handle position depends on the fastening setup and available working space.

Setup & Operation

Before operating an EFW Electric Torque Multiplier:

Determine the required fastening torque.
Select the appropriate EFW model.
Select the appropriate socket.
Install the reaction device.
Connect the multiplier to the appropriate electrical supply.
Select the required torque setting and direction.
Place the socket or connector completely on the fastener.
Position the reaction device against a safe, stable support.
Keep the multiplier properly aligned with the fastener.
Activate the tool.
Allow the multiplier to operate until the motor stops at the preset torque.
Change direction and briefly operate the tool as needed to free the reaction device.
Remove the tool and move to the next fastener.

For EFW Plus models, follow the applicable Plus operating instructions for torque and angle settings.

Tool Alignment & Safe Operation

Mountz's operating instructions specify that the electric multiplier should remain properly aligned during fastening to avoid side loading.

During operation:

Completely engage the socket or connector with the fastener.
Keep the multiplier aligned with the fastener axis.
Keep the reaction device at the same level as the socket or connector.
Use a safe and stable reaction point.
Keep clothing, hair, and loose objects away from moving parts.
Keep hands away from the reaction device.
Wear appropriate protective equipment.
Do not leave the multiplier unattended while it is operating.

Remote-Control & All-Weather Options

Mountz states that remote-control operation and all-weather models are available for EFW Electric Torque Multipliers.

These should be treated as available configurations rather than standard features of every EFW model.

Calibration & Accuracy

EFW Electric Torque Multipliers provide accuracy better than ±5%.

Follow the applicable operating instructions and your organization's calibration requirements when maintaining the multiplier.

I have not included a specific recalibration interval here because, although the older electric multiplier manual contains service guidance, I don't want to present a historical interval as a current EFW requirement unless Mountz's current documentation explicitly confirms it for these current models.

Common Applications

Mountz specifically identifies EFW Electric Torque Multipliers for:

Precision tightening of heavy-duty fastening connections
Precision loosening of heavy-duty fastening connections
Windmill gearbox assembly
Oil & gas pipeline bolting maintenance
Oil & gas rig bolting maintenance
Heavy-duty assembly operations
Heavy-duty maintenance operations

Common Industries

Based on the applications specifically identified on the EFW product pages, primary industries include:

Wind energy
Oil & gas

Mountz's broader torque multiplier product information also identifies torque multipliers for applications in aerospace, transportation, mining, marine, oil/gas, and power generation. These are broader torque-multiplier applications and are not stated as EFW-specific industries.

Use Cases Windmill Gearbox Assembly

Problem: Large industrial bolts used in windmill gearbox assemblies require precision high-torque fastening.

Solution: EFW Electric Torque Multipliers provide controlled electric torque with automatic shut-off and smooth, continuous rotation. Mountz specifically identifies windmill gearbox assembly as an EFW application.

Oil & Gas Pipeline Maintenance

Problem: Pipeline maintenance requires precision tightening and loosening of heavy-duty bolting connections.

Solution: EFW Electric Torque Multipliers provide controlled high-torque electric operation for bolting maintenance applications on oil & gas pipelines.

Oil & Gas Rig Maintenance

Problem: Rig maintenance includes heavy-duty bolting applications requiring controlled high torque.

Solution: EFW models provide precision tightening and loosening across torque capacities up to 7,228 lbf.ft.

EFW Electric Torque Multipliers vs. Hydraulic & Impact Tools

Mountz directly compares its electric torque multipliers with hydraulic and impact wrenches.

According to Mountz, EFW Electric Torque Multipliers:

Operate 5–10 times faster than slow-ratcheting hydraulic wrenches.
Are less expensive than hydraulic wrenches.
Provide smooth, continuous, non-impacting rotation.
Eliminate the hammering associated with impact wrenches.

These are Mountz's stated product benefits rather than general assumptions about every hydraulic or impact system.

Maintenance

Mountz identifies the EFW's brushless motor design as low maintenance.

For operation and care:

Inspect the tool and accessories before use.
Inspect the socket or connector before fastening.
Inspect the reaction setup before operation.
Keep the power cord protected from damage.
Do not operate damaged equipment.
Follow the current operating instructions for service and maintenance requirements.

Internal service or repair should follow Mountz's applicable service procedures.

Compatible Accessories Reaction Devices

Mountz offers the following types of torque multiplier reaction devices:

Reaction Foot
Reaction Bar
Reaction Ring

EFW multipliers are supplied with a reaction foot. Other reaction devices should only be used when compatible with the specific multiplier and application.

Retention Rings

Mountz offers retention rings for torque multipliers. They are used to hold a reaction foot, bar, or ring on the multiplier.

Impact Sockets

Mountz offers 6-point impact sockets within its socket product offering. Select sockets based on the required drive size, fastener size, and application requirements.

Current EFW400, EFW600, EFW800, and EFW1000 models all use a 1 1/2-inch square drive.

EFW Electric Torque Multipliers – FAQ & User Guide