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Hydraulic Torque Wrenches by Powermaster Industrial.
Hydraulic Torque Wrenches - A Brief History.
A torque wrench is a tool used to precisely apply a specific torque to a fastener such as a nut or bolt. It is usually in the form of a socket wrench with special internal mechanisms. It was invented by Conrad Bahr in 1918 while working for the New York City Water Department. It was designed to prevent over tightening bolts on water main and steam pipe repairs underground.
A torque wrench is used where the tightness of screws and bolts is crucial. It allows the operator to measure the torque applied to the fastener so it can be matched to the specifications for a particular application. This permits proper tension and loading of all parts. A torque wrench measures torque as a proxy for bolt tension. The technique suffers from inaccuracy due to inconsistent or uncalibrated friction between the fastener and its mating hole. Measuring bolt tension (bolt stretch) is more accurate but often torque is the only practical means of measurement.
A hydraulic torque wrench is a tool designed to exert torque on a fastener to achieve proper tightening or loosening of a connection through the use of hydraulics. A torque wrench is applied to the nut either directly or in conjunction with an impact socket. Hydraulic torque wrenches apply a predetermined, controlled amount of torque to a properly lubricated fastener. The hydraulic torque wrench was invented by George A. Sturdevant in Houston, Texas. The concept of a hydraulic powered torque wrench was first introduced on the market sometime in the early 1960s in a primitive form, and several key advances have been developed by manufacturers since that time which provided major advancements in the technology and usability of the tools far beyond the original concept tool. Today's tools offer benefits such as lighter weights, smaller nose radius dimensions for fitting into tight spaces, use of exotic alloys, actuation triggers on the tool itself, multi-position reaction members, 360° x 360° hose swivels, and the ability to run multiple tools simultaneously from a single power pack.
The main characteristics of a hydraulic torque wrench which set it apart from other powered wrenches of similar function are that (1) it must generate torque using only hydraulic means (2) it must be self ratcheting, and (3) it must include an accurate method of determining the amount of torque applied. Some manufacturers utilize a holding pawl design to keep the wrench locked in position prior to each power stroke, others use varying designs, which as in all industries have debatable faults or claimed advantages. Hydraulic torque wrenches typically offer accuracy of +/- 3% and have a high degree of repeatability making them well suited to applications where large bolts are involved and a high degree of accuracy is required. A hydraulic torque wrench is significantly quieter, lighter weight and more accurate than pneumatic impact wrenches capable of similar torque output, making it an appealing alternative for many users to the very loud and cumbersome impact wrenches or torque multipliers which were formerly the only viable option for working with very large nuts and bolts until the hydraulic torque wrench was introduced.
Powermaster Industrial Supplies 2 main types of Hydraulic Torque Wrenches:
- PSD Series Square
Drive Hydraulic Torque Wrenches.
- PXD Series Low Clearance Hydraulic Torque Wrenches.
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PSD Series |
PXD Series |
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The PSD Series Square Drive Series have a 7075 Aircraft Quality Specification housing and have just 3 moving parts, ensuring ease of operation and maintenance. |
The PXD low clearance series are made from AISI 4340 Aircraft Quality High Strength Alloy. The flat design and small width of the PXD series ensures flat positioning on the flange surface and fits even the most hard to reach applications. |
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