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Hydraulic tensioners for compact flanges

Boltight’s Xtra Load range of bolt tensioners is used extensively in the offshore oil and gas industry for bolting compact flanges.

The 1500 bar system delivers 30% more load than Boltight’s standard range in a smaller space envelope without compromising on safety, reliability and accuracy. This lightweight and innovative design was developed to suit all common sized ANSI, API and Norsok L005 compact flanges.

Watch the video demonstrating the tensioning process with Xtra Load tensioner.


Click here for more information about Boltight.

Expander System saves a day of work

Gamleby Forest is a logging company with a number of harvesters in their fleet. The machines generally operate year round and eliminating expensive downtime is always a priority at Gamleby.

Upon inspection of one of the harvesters, the machine operator discovered a wear in the lugs between the boom and pillars. The owner of the company, who often does repairs himself, had some experience with the Expander System in the past. He immediately decided to replace the original pin in the harvester with the Expander solution.

The whole replacement process took merely two hours. The Expander solution was installed directly into the worn lugs. The double-sided locking on the Expander pivot pin provided increased stability, security and minimized wear in the joint.

If Gamleby Forest chose to use a new original pin instead of pivot pin from Expander, they would have to transport the harvester to their workshop to mount the pin there. Practically a whole day would be required to complete the replacement. A traditional repair, moreover, would only solve the problem for the moment – wear would occur again.

After the replacement the harvester was back in the operation within a couple of hours and Gamleby Forest became yet another satisfied customer of the Expander System.

Quadrupled machine life and thousands of dollars saved

The Yanacocha Mine in Northern Peru is one of the largest gold mines in the world. As in any industry, downtime means lost productivity and – as a result – lost money. Keeping the operations running is always of the utmost importance.

Minimizing production shortfalls and lowering the life cycle cost of the machinery and equipment is a constant challenge for the service and maintenance crew.

The useful life of the conventional pins in the stabilizer linkage on CAT’s 793B fleet was calculated to be 5.000 hrs. The machine was then brought in for disassembly, line-boring and re-pinning as part of crew’s maintenance schedule.

In 2003 the decision was made to put Expander System to the test.

A mining truck was fitted with pivot pins from Expander System and they outlasted the conventional solution by four times. The Expander pivot pins were checked every 5.000 hours and were not replaced until the 20.000 hour maintenance check. During the replacement no line-boring was needed and the whole procedure was completed in a few hours instead of days as it would in case of the conventional solution.

The cost savings where Expander pins were fitted were calculated to be over $30.000. While the test was ongoing and proven successful, the Yanacocha Mine maintenance department decided to start using the Expander System in many other pivot applications on their haul truck fleet.

The Yanacocha Mine is also using the Expander System on several vital wear points on Motor Graders and Wheel Loaders.

Hydraulic tensioning with Multi Stud Bolt Tensioner

Multi Stud Bolt Tensioner is designed to provide high and accurate preload within a minimum diameter envelope. Durable, lightweight and easy to use, these tools are ideal for use within the confined radial spaces typical to tower connections.

The video below demonstrates the tensioning process.

Click here for more information about Boltight.

Pressing problem solved with Superbolt

18 January 2017

Text: Carol Akiyama

photo: Sodick

Bolted joints are a key component of most machines, which make them essential to many of Japanese Sodick Corporation’s applications. The company manufactures industrial machines and machining tools as well as consumables and other products. Original research and development is a top priority, ensuring high-quality products that improve the customers’ manufacturing operations.

First published in Bolted #2 2016.

Bolted joints are a key component of most machines, which make them essential to many of Japanese Sodick Corporation’s applications. The company manufactures industrial machines and machining tools as well as consumables and other products. Original research and development is a top priority, ensuring high-quality products that improve the customers’ manufacturing operations.

Sodick moulding machine engineers recently attended a seminar on solutions to the problem of loose bolts held by Ikeda Metals, a Nord-Lock Japan distributor. It touched upon exactly what they were struggling with.

Together with Ikeda Metals engineers, Nord-Lock engineers started searching for areas where they could help improve Sodick’s bolted joint design. They realized that in the Sodick moulding machines, the tie rod bolts were tightened by a traditional method. Tie rods are quite long, so if they are subject to torsion stress, and the machine is operating for a long time at the end-customer site, it is difficult to guarantee optimal performance. From the customer’s perspective, the ability to properly control the force on the joints becomes essential, because it is key to safe operation without costly downtime.

Superbolt was the perfect solution as it just has pure tension. It does not create any friction and therefore can control the force on the joints without giving off torsion stress. The people at Sodick were impressed by how diligently the Nord-Lock engineers worked at finding solutions that catered specifically to their application needs.

Superbolt tensioners are premium products and while there are cheaper alternatives in the market, Sodick firmly believes that the cost performance of the product makes it appealing. About half of Sodick’s products are sold overseas, and some big machines cannot be shipped assembled. It is essential that the moulding machine assembly and changing of parts can be carried out easily, quickly and safely at the end-customer site. Sodick is pleased to hear reports that their customers are satisfied with having smooth, speedy operations.

New horizons with the Expander System

Operating for over 80 years, Boskalis Westminster is a leading global dredging and offshore contractor and maritime services provider. With safety and sustainability as their core values, the company has a long track record of successfully completing projects in different types of challenging offshore environments.

Among the multitude of machines and equipment Boskalis can boast, their fleet of dredgers is particularly impressive. In demanding offshore environments with limited MRO access, efficient and problem-free operations are crucial.

For one of their biggest dredgers – backhoe dredger Baldur – Boskalis has chosen Expander as their supplier of pivot pins.

Expander solutions are developed to function in extreme environments like the offshore industry, and Boskalis did not hesitate to put them to the test.

The pivot pin supplied by Expander for this project, mounted between the boom and dipper arm, is by far the largest that the company has designed and manufactured inhouse. The pin is 2230 mm long with a diameter of 320 mm and weights a whopping 1.5 tons. The sleeve alone weights 95 kg.

Downtime and production shortfalls due to pivot wear are no longer an issue for Boskalis. Expander’s design has prolonged the life span of their dredger fleet and improved their performance.

Tightened just right

4 January 2017

Text: Chad Henderson

photo: Getty Images

First published in Bolted #2 2016.

Project: San Francisco–Oakland Bay Bridge
Overall project cost: $6.4 billion
Application: Replacing the bridge’s east span
Boltight solution: Hydraulic bolt tensioning of cable band bolts
Contractors: American Bridge/Fluor

Engineering projects don’t get much bigger. A suspension bridge with only one tower, on limited bedrock, with ten lanes of traffic that has to be able to withstand the largest earthquake expected over a 1,500-year period.

In a 2006 joint venture contractors American Bridge and Fluor got the assignment to build the new eastern span of the San Francisco–Oakland Bay Bridge, the largest public works project in California’s history.

Most suspension bridges have multiple towers, explains Brian A. Petersen, Vice President – Western Region, American Bridge: “This bridge span only had a single tower and is essentially anchored on itself. The main cable is seated in the deck, which is an extremely involved structural engineering design achievement.”

A total number of 114 cable bands, secured around the main cable to keep the suspender ropes in place, needed to be bolted with exactly the right amount of tension. High-strength rods, which secured both the main tower as well as the bearings and shear keys at the bridge’s east end, required a high-capacity jacking system to obtain the large clamping force that the bolts were required to achieve. Over 2,000 fasteners were tensioned using the Boltight hydraulic bolt tensioners.

“Boltight’s system elongates the rod and tightens the nut, but never turns the rod, which was an important design requirement,” says Petersen. “Their equipment allowed us to properly tension the high-strength rods and bolts in a very limited space. The equipment had a high level of accuracy, and our workers could easily carry it around. No other manufacturer could meet our requirements.”

Merry Christmas from the Nord-Lock Group

As the holiday season is upon us, the Nord-Lock Group would like to take this opportunity and wish everyone Merry Christmas and Happy New Year! With recent acquisitions and new technologies in our product portfolio it’s been quite a year for us all! We hope that 2016 has been just as memorable for you and everyone who has been helping us fulfil our mission of safeguarding human lives and customer investments.

This year the Nord-Lock Group is making a donation to Reach for Change charity on behalf of all employees. Reach for Change is an organization that finds exceptional social entrepreneurs – people that are passionate about creating a better world for children and who have an innovative idea on how to do it, and then helps them succeed. Read more at