Difficult Bolting Applications Require Custom Solutions

Some bolting jobs become difficult before the tool ever reaches the fastener. Tight clearances, overhead obstructions, and the weight of larger hydraulic tools can make simply getting the equipment into position one of the hardest parts of the job.

Winshaw ran into that problem on a project where a heavy bolting tool needed to be positioned over a fastener, but an overhang ruled out the usual overhead lifting methods. Instead of suspending the tool from above, Winshaw developed a custom tray that supported and positioned it from underneath.

Why the Usual Lifting Method Wouldn’t Work

The fastener was located beneath an overhang, leaving no practical place for a winch, tool balancer, or other overhead support.

That mattered because the bolting tool was too heavy to treat positioning as a simple hand-lifting job. The operator needed a way to bring the tool into position, hold it there during the bolting operation, and remove it without repeatedly handling the full weight.

A support system underneath the tool solved that problem.

How Winshaw’s Custom Tray Worked

Winshaw designed the tray so the bolting tool could rest on a supported platform beneath the fastener.

The operator could bring the tool into position, raise it until it lined up with the nut, and lower it into place without carrying the tool’s weight by hand. Once the bolting work was complete, the tray could lift the tool away and move on to the next fastener.

That same motion could then be repeated across multiple bolting locations.

What Matters in the Tray Design

The tray has to do more than simply hold the tool.

Tool support: The tray and its mounting need to handle the weight of the tool and the loads created while it is being positioned.
Alignment: Guides, locating points, or pins can help bring the tool back to the same position over each fastener.
Vertical movement: The lifting method needs enough travel to place and remove the tool without running out of clearance.
Restraint: The tool needs to remain secure while torqueing or tensioning work is underway.
Hose routing: Hydraulic hoses and other connections need a path that keeps them away from pinch points and surrounding structure.
Service access: Wear points and working components should still be reachable for inspection and maintenance.

Depending on the application, vertical movement may be mechanical, hydraulic, or pneumatic. The right setup depends on the tool, available space, required travel, and how often the operation will be repeated.

What Changed for the Crew on Site

The biggest difference was that the bolting tool no longer had to be repeatedly supported by hand.

The tool could be brought back to the same working position from one fastener to the next.
Operators spent less time physically handling the tool’s full weight.
The tray provided a workable option in an area where overhead lifting equipment could not be installed.
The tool stayed supported between bolting points instead of being lifted and repositioned from scratch each time.

That made the tray useful not only for one difficult fastener, but for a series of repeated bolting operations in the same restricted area.

Planning a Support Tray for a Bolting Job

A custom tray starts with the actual space around the fastener.

The tool’s weight may not sit evenly on the tray. Mark the area carrying the load so the support can be built around the way the tool actually rests.
Around the fastener, the overhang is what sets the working envelope. Use that narrowest clearance as the dimension the tray has to work within.
With the tool lined up over the nut, record how much lift is needed to seat it and how far it has to rise before it can move away cleanly.
Decide how the tool will be guided into the same position each time.
Identify how the tool will be restrained during the bolting operation.
Check hose and connection routing through the entire travel range.
Leave access for inspection and maintenance wherever possible.

Photos can help, but detailed measurements are usually what determine whether the idea will work once steel is fabricated.

Build Around the Actual Work Area

One of the easiest mistakes with a custom fixture is designing around the tool while overlooking everything surrounding it.

A tray may have enough capacity to hold the equipment and still fail to fit between nearby structure. The same problem can happen with hose connections, handles, reaction points, or the extra clearance needed to lift the tool away after the bolting cycle.

That is why the work envelope needs to be measured before fabrication begins.

custom tray for positioning heavy-duty bolting tools

Planning Checklist for the Site

Confirm tool weight and center of gravity relative to the tray support points.
Measure nearby structure and the available clearance around the fastener.
Record the vertical travel needed to install and remove the tool.
Identify the locating points needed to bring the tool back into alignment.
Determine what locking or restraint features are required during operation.
Map hydraulic hose and connection routing before finalizing the tray.
Make sure inspection points remain accessible once the tray is installed.

A stubborn or hard-to-reach bolting location does not always require a different bolting tool. Sometimes the better answer is changing how the existing tool is supported and positioned.

For tool-specific guidance on accuracy and maintenance, see Hydraulic torque wrench tolerances and How often should you calibrate and/or certify your torque tool. For additional bolting guidance, see considerations when using hydraulic bolt tensioners.

Build Around the Overhang

On this job, the overhang above the fastener set the limit. Before cutting steel, Winshaw needed to know how much room the tray had underneath it and how far the tool had to lift to clear the nut. If the site cannot be reviewed in person, photos with a tape measure in the frame can capture those dimensions.

From there, Winshaw can review the application, develop a concept for supporting the tool, and work through how the fixture will be used and inspected once it is on site.

Contact Winshaw for Custom Bolting Support

If you have a bolting application where access, tool weight, or surrounding structure is making the job difficult, email sales@winshawllc.com.

Include the fastener size, tool being used, available clearance, and a few photos or measurements of the work area. That gives Winshaw a better starting point for determining whether a custom tray or other support fixture makes sense for the application.

Hydraulic bolt tensioners are used to stretch a bolt in a controlled way so the nut can be seated before the hydraulic pressure is released. The pressure reading matters, but it is not the only thing that determines the load left in the bolt afterward.

The joint itself, the condition of the equipment, and the way the tensioning cycle is carried out can all change the final result.

Material Differences Across the Joint
Bolt, nut, flange, and gasket materials: These components do not all react to load the same way. Surface finish, compression, and elastic behavior can affect how much preload remains after hydraulic pressure is released.
Gasket behavior: One area of the gasket may compress farther than the rest as the joint seats, which can leave that location with a lower residual bolt load.
Component condition: Damaged threads or a seating face that is not flat can show up as a nut that does not run down or seat normally.

Dimensions Matter Too

A rough or damaged thread can make one nut run down differently from the others.
Check the seating face closely. If the nut is not sitting flat, the final load can be off even when the hydraulic pressure was correct.
Gasket thickness is worth noting too, especially if one section compresses more than the rest of the joint.
Variations between neighboring bolting locations may produce different residual loads even when the same hydraulic pressure is used.

This is one reason the joint should be treated as a complete system rather than looking only at the tensioner pressure.

Operator Technique Can Change the Result

The tensioning sequence matters, especially when several bolts are being worked together.

A consistent procedure helps keep one bolt from being treated differently from the next. Pressure should be applied and released according to the specified procedure, and the required tightening or tensioning sequence should be followed for that joint.

When several bolts are tensioned at once, the order of work becomes even more important because loading one area can affect another.

Some Load Is Lost During Transfer

The hydraulic load applied by the tensioner is not necessarily the exact load that remains in the bolt after the tool is removed.

Some load can be lost as the nut seats and the joint settles. That is why the required hydraulic load, residual bolt load, and any load-transfer allowance need to come from the approved procedure or engineering requirements for the joint.

Do not assume that the pressure shown on the gauge translates directly into the final retained bolt load without accounting for the tensioning procedure being used.

Keep the Pressure Gauge in Calibration

The gauge is one of the operator’s main references during tensioning.

If the gauge is reading incorrectly, the pressure being applied may not be the pressure the operator thinks is being applied. That error can carry through an entire group of bolts if it is not caught.

Gauge calibration should follow the interval required by the company’s quality system, the equipment manufacturer, and any applicable job requirements.

Equipment Condition Shows Up in the Cycle

A tensioner with worn seals, damaged components, or leaking hydraulic connections may not behave the same way it did when it was in good condition.

Look at the complete system:

Tensioner body and puller components.
Seals and collars.
Hydraulic hoses and fittings.
Pump condition.
Pressure gauge condition.
Connections between the pump and tensioner.

At target pressure, the gauge needle should settle. If it keeps creeping backward, the system is not holding pressure as it should.

Quick Troubleshooting Checks

When one bolt comes back low and the others are close, look at that location first. A nut sitting crooked on the seating face can be enough to change the result.
A falling gauge reading during the cycle may point to leakage or another hydraulic issue that needs to be investigated.
Damaged threads or poor nut seating can change the result even when the hydraulic system is working correctly.
Critical joints may require another inspection after initial seating or after the equipment has reached operating temperature or pressure, depending on the procedure being followed.

Maintenance and Verification

Regular inspection of the tensioners, hoses, pumps, and gauges helps catch problems before they show up during a bolting job.

Keep service and calibration records with the equipment so there is a history to refer back to if performance changes. If a hose, fitting, seal, or other component is damaged, take care of it before the next critical tensioning cycle rather than trying to work around it.

For more on calibration frequency and documentation, see:

What is the difference between calibration and certification

How often should you calibrate and/or certify your torque tool

Practical Operator Checklist

Check the bolt and nut condition before installing the tensioner.
Make sure the threads are clean and lubricated as required by the job procedure.
Look over the gasket and seating surfaces for anything that could affect how the joint closes.
Verify that the pump and pressure gauge are ready for service before beginning critical work.
Follow the specified tensioning sequence instead of changing the order in the field.
Apply and release pressure in the manner called for by the procedure.
Record the pressure used and anything unusual that happens during the cycle.
When several bolts are being tensioned, follow the pattern specified for that joint rather than working around it in an improvised order.

Custom Tool Tray for Bolting in Hard-to-Reach Areas