Square Drive Kit (Blue-Point®) – YA391RK

The multiplier square drive kit YA391RK belongs to the Blue-Point® square drive kits for geared head multipliers range, and Lost in HCM supplies it to workshops and factories across Vietnam. Snap-on lists the country of origin as USA.

Multiplier square drive kit YA391RK overview

The multiplier square drive kit YA391RK is a Blue-Point® service part for geared head torque multipliers. It restores the output square drive, which carries full multiplied torque to the socket. So a worn drive no longer forces you to replace the whole tool.

Snap-on lists the USA as the country of origin for every kit in this family. Some kits carry the name Square Drive Kit, while others are Square Drive Replacement Kits. In both cases, you match the kit number to your multiplier model before you order.

Specifications at a glance

The table below follows the Snap-on data for YA391RK. In addition, we converted imperial torque values to N·m where Snap-on lists none.

How the multiplier square drive kit works

A geared head multiplier uses gear stages to multiply the torque you apply at the input. Meanwhile, a reaction arm braces against a fixed point, so the tool body cannot spin. Then the output square drive turns the socket with the multiplied torque.

Because the square drive carries the highest torque in the tool, it sees the most stress. On many multiplier designs, the output square is the intended weak point. As a result, it can fail first and protect the gears from overload.

Key features of the multiplier square drive kit YA391RK

Every kit in this family serves the same purpose, which is to renew the multiplier output drive. Here are the points that matter most when you plan spares. They also show why a kit often beats a new tool.

• Restores the output drive. The kit renews the square drive that delivers multiplied torque to the socket. Therefore, a worn output does not force you to replace the whole multiplier.
• Blue-Point® parts range. These kits come from Blue-Point®, a Snap-on brand, for its geared head multipliers. So you get a part that matches the original multiplier design closely.
• Two kit types. The family includes both Square Drive Kits and Square Drive Replacement Kits. Check the product name and your manual, because each kit suits specific multiplier models.
• Made in the USA. Snap-on lists the USA as the country of origin for every kit in this family. In addition, the kits ship with CO/CQ papers when you buy through Lost in HCM.
• Less downtime during shutdowns. A spare drive kit lets your team repair a multiplier on site in a short time. As a result, bolting work during a plant shutdown keeps moving.
• Keeps the gearbox in service. Replacing only the square drive usually costs far less than buying a new multiplier. Meanwhile, the gearbox and reaction arm you already trust stay in service.

Typical applications

These kits solve one problem well: getting a multiplier back to work after drive wear. Below are typical jobs where that matters, from shutdowns to field service. Each one also rewards a spare kit on the shelf.

• Worn output drive repair. Square drives round off after many socket changes and heavy pulls. A new kit restores a tight socket fit, so the multiplier delivers torque safely again.
• Overload damage recovery. An overload can twist or break the output square on a multiplier. Then a replacement kit returns the tool to service without a full gearbox repair.
• Shutdown spare parts stock. Plant shutdowns leave little time to wait for tool repairs or new tools. So maintenance planners keep drive kits in stock before large bolting campaigns begin.
• Wind and power bolting. Wind turbine and power plant crews use multipliers on large flange and foundation bolts. Therefore, a spare drive kit protects the schedule when a drive wears out.
• Heavy equipment track work. Mining and construction workshops use multipliers on track, sprocket, and wheel bolts. In addition, harsh site use wears drives faster, so spare kits keep tools ready.
• Preventive tool maintenance. Some tool cribs replace output drives on a schedule instead of waiting for failure. That way, every multiplier leaves the crib with a sound socket fit.

Industries that use the multiplier square drive kit YA391RK

Any sector with large bolted joints puts heavy wear on multiplier drives. So spare kits show up in wind farms, mines, and plants. Here is how each industry uses them in practice.

• Wind and renewable energy. Wind farms in Ninh Thuan and Bac Lieu tighten tower and blade bolts with multipliers. So service crews keep drive kits on hand to avoid stopping work.
• Mining and quarrying. Coal mines in northern Vietnam use heavy equipment with very large bolts on tracks and frames. Therefore, multipliers work hard there, and spare square drives keep them in service.
• Oil and gas. Offshore and onshore teams in Vung Tau torque flange bolts on pipelines and vessels. In addition, remote sites need spare parts on hand, so drive kits travel with the tools.
• Heavy equipment dealers. Dealer workshops for FDI equipment brands in Vietnam rebuild tracks, final drives, and frames. Meanwhile, their multipliers see daily use, so worn drives need quick replacement from stock.
• Steel and cement plants. Steel and cement plants run crushers, kilns, and mills with large bolted joints. So maintenance teams use multipliers often and stock drive kits for planned outages.
• Shipbuilding. Shipyards in Hai Phong and Ha Long bolt engines, rudders, and deck machinery to strict values. Also, yard tools take hard knocks, so spare output drives keep multipliers working.

Multiplier square drive kit YA391RK compared with similar brands

Before you choose a fix, it helps to see how the multiplier square drive kit YA391RK compares with other options. However, the right answer depends on the multiplier you own. Instead of price alone, compare fit, downtime, and long-term reliability.

If your team runs Blue-Point® geared head multipliers, the matching drive kit is the simplest fix. It restores the output without replacing a sound gearbox. Even so, confirm current specs and fit with each maker before you order. Specifications change over time, so confirm current data with each maker before you decide.

Choosing the right model

• Match the kit number to your multiplier model before you order. The product name and your tool manual both help you confirm the right kit.
• Check whether you need a full Square Drive Kit or a Square Drive Replacement Kit. Ask us if the manual does not make the difference clear.
• Inspect the old drive closely before you order a new one. Twisting or cracks can point to overload, so review your torque settings as well as the part.
• Keep at least one spare kit for each multiplier model in your crib. That way, a worn drive does not stop a planned shutdown.
• Check your sockets when you replace the drive. A worn socket can damage a new square quickly, so replace both if needed.
• Plan the swap with the tool manual at hand. Follow the Blue-Point® steps for your model, and test the tool at a low load afterward.

For other sizes in the same range, compare Square Drive Replacement Kit (Blue-Point®) – YA395RK, Square Drive Kit (Blue-Point®) – YA392RK, Square Drive Kit (Blue-Point®) – YA394RK, Square Drive Replacement Kit (Blue-Point®) – YA393RK. Also browse the full Snap-on torque tools shop for handles, testers and adapters.

Care, storage and calibration

• Store spare kits in their packaging in a dry cabinet. Then the steel stays clean and free of rust until you need it.
• Clean the output area of the multiplier after each job with a dry cloth. Also check the square for burrs, because burrs can damage sockets.
• ISO 6789-1:2017 sets a 12-month or 5,000-cycle interval for hand torque tools. Apply a similar plan to your multiplier, and we can arrange recalibration through an accredited laboratory.
• Never exceed the multiplier's rated output torque or drive the input with an impact tool. An overload can twist the new drive, so check settings before each job.
• Carry the multiplier and spare kits in a padded case between sites. In addition, keep them dry during the rainy season to protect gears and drives.

Frequently asked questions

Request a quote

Send us the part number, quantity and delivery site, and we will reply with a quote. You can request a quote online or call 0902 327 669.