Valley Forge & Bolt Mfg. Co.

United States

A fastener is modified by machining a small hole into the head. Minimal modifications to the bolt assure basic bolt design integrity. A gage pin is then inserted into the hole and secured at the bottom. Next, a datum disk is fitted on the top of the bolt head and forms a flat surface with the top of the gage pin when the bolt is unloaded. When the bolt is tightened, it elongates and the gauge pin is drawn into the bolt away from the datum disk surface. A portable electronic displacement transducer measures the distance between the datum disk surface and the tip of the gage pin. The elongation of the bolt is then correlated to joint clamp load via our electronic or mechanical hand held monitors.

The Ball Lock Washer is a hardened washer, which employs the use of hardened steel ball bearings that embed and grip into the flange face and nut bearing surfaces. This mechanical lock begins to occur during the hand tightening stage and is maintained throughout the tightening process. The length of time it takes to assemble a joint is greatly reduced since the operator can quickly maneuver a single tool around the flange. This unique system works both when tightening and loosening. It can be used under the nut, when tightening the head, or used under the head, when tightening the nut. The result is a technology that eliminates the need for a back-up wrench and the need for an operator to place his hands and fingers at risk in a pinch point zone.

The Clarkester™ Tester accurately calibrates tightening tool torque to bolt tension, prior to installation, to virtually eliminate loose and broken bolts in structural and mill liner applications. The Clarkester™ is available with load capacity up to 250, 000 pounds and bolt sizes up to 2 ½”. In addition, torque capacity is considerably higher than that of currently available testers, thereby enhancing the integrity of your bolted joints.

When Grinding Mills age, the location in the shell for liner bolt nuts can become worn. This can cause slurry leakage. Slurry leakage is a real problem. It cuts through the shell and makes the leak grow and grow: a viscous cycle. By using our Pitbull™, this can mitigate any more damage from happening until there can be a complete repair of the hole created from a bolt boring around. Our Pitbull™ Liner Washer grips and holds like no other washer can. The Pitbull™ Liner Washer is one of our most popular washers because they hold like a “pitbull’s bite”, and provides that stable platform needed in worn areas. In addition, for bolt diameters of: 1 ¼”, 1 ½”, 2″ (M48 and M52), we even have an Oversized Pitbull™ made to cover a badly worn bolt hole area, on the shell. Our newest creation, in this respect, is a Double Sided Pitbull™ Liner Washer. This washer was developed because, often times, a liner bolt is not initially manufactured long enough to allow for both the Pitbull™ Liner Washer and the Two Piece Sealing System to fit. Then, when an enlarged shell hole occurs as the mill ages, and needs a Pitbull™, the liner bolt must be replaced with a new, longer bolt to accommodate both systems. Now there is another option. The Double Sided Pitbull™ is the solution to accommodate both systems without requiring an entirely new, longer bolt.

With the VF Two Piece Mill sealing System, the counter bore forms a pocket to contain the outer diameter of the neoprene sealing washer. The sealing washer is thicker than the counter bore depth, and protrudes out of the forged washer. This is by design and meant so that when squeezed, a seamless seal will form around the liner bolt threads and at the shell face giving a leak free, tight system, when properly installed. The neoprene washer is meant to squeeze until the forged washer outer ring becomes solid against the shell, at approximately 150 foot-pounds of torque.

The Ridgeback™ Liner Bolt was designed by our engineers especially to solve bolting problems that users were encountering when liners were installed. With standard bolts, there is a 18″ all-around clearance between the bolt and the liner; therefore, when the bolt is installed, it rests on two points and is not stable. To stabilize the assembled joint, our engineers designed ridges along the taper section of the bolt to conform to the tapered surface of the liner hole when assembled. These ridges plastically deform during assembly to take the individual shape of the tapered liner seat and bolt seat, creating a solid surface to tighten against.

The integrity of a bolted joint is jeopardized when fasteners lose their tension. This loss of clamping force begins during assembly due to elastic interactions and joint relaxation. Self-loosening continues when the joint is put in service due to vibrations, shock, temperature changes, embedment, etc. The SPC4™ joint allows the end-user to re-tighten only the bolts or studs that have lost their clamp load. This results in a tremendous saving of maintenance time, money and replacement parts. For a minimal investment, the SPC4™ offers maximum joint integrity with optimum performance.

Now introducing Wireless Load Monitoring and Data Logging with the SPC4™ technology. Designed to your specific application, the wireless and data logging capabilities are tailored to your needs. Contact us today to receive a product specification sheet with all the possibilities for your application.

With five different models to chose from, there really is a reader for every application. Featuring portable and pocket sized options with both analog and digital reading capabilities. Each reader displays bolt load (joint clamp load) as a percentage of its proof or yield load (customer choice). There are optional abilities to electronically control the installation tool to a pre-set clamp load, as well as data storage and upload for analysis capabilities. Visit the Instructional Videos page to learn more and watch videos on how each SPC4™ Reader works and operating instructions.

The Maxbolt™ is manufactured by inserting extremely accurate and durable load monitoring devices into high quality bolts and studs. The accurate assembly and continuous monitoring capabilities reduce the potential for premature wear, expensive downtime, and catastrophic joint failure. In addition, load-indicating fasteners are compatible with conventional tightening and tensioning equipment and eliminate the need for costly ultrasonic, strain gages, and torque measuring devices. Now, even inexperienced operators can assemble complex bolted joints with uniform clamp loads within +-5% of design specification. Because measurements are based on tension, the inaccuracies of torque control are eliminated, ensuring optimum initial conditions before an assembly is placed into service.

Now introducing Wireless Load Monitoring and Data Logging with the SPC4� technology. Designed to your specific application, the wireless and data logging capabilities are tailored to your needs. Contact us today to receive a product specification sheet with all the possibilities for your application.