Product Description
Bridging Pit Gauge System
The Bridging Pit Gauge System allows the Corrosion Inspector to Span over or Cantilever into Large Areas of Weight Loss Corrosion, to obtain accurate and consistent measurements, or cross sections, of Pit Depth. As conditions dictate, the operator can simply use the Main Blade or can assemble the Bridging Pit Gauge up to an over all length of 28" (725mm).
The contact Surfaces (Blades) of the Bridging Pit Gauge are fitted with an exclusive Knife Edge, so they can be used on Flat, ID (Convex), and OD (Concave) Surfaces, where a flat or notched contact surface can introduces error on Convex Surfaces. Like our Standard Pit Gauges, the Knife Edge gives the operator a clear view of the contact point, and the area being inspected.
With the addition of the optional Magnetic Hold Downs, the operator uses their width to quickly align the Bridging Pit Gauge System to a curved surface. This leaves his hands free to scan through very large areas of weight loss corrosion. This holds true when the Bridge Elements have been assembled with a slight contour on an irregular surface.
Name | Part# | Description |
---|---|---|
Bridging Pit Gauge |
N88-9 | Main Blade, Imperial Dial Indicator, Connector Blade, 2-Extender Tees, End Blade, Slider Blade, Hardware, Extra Contact Point, and Carrying Case. |
Main Blade | N88-9-1 | Center and End Dial Indicator Mounting Positions, Cutaway Nose for next to welds. 5.5" (144mm) long. |
Connector Blade | N88-9-2 | Joins Tee Sections to increase length. 3.5" (90mm) long. |
End Blade | N88-9-3 | Mounts on end of Tee for extra contact. 1.5" (38mm) long. |
Slider Blade | N88-9-4 | Extra Point of Contact and doubles as an End Blade in Spanning Configuration. 1.5" (38mm) long. |
Extender Tee | N88-9-5 | Extends effective length of all models. 12" (305mm) long (Longer Tees are optional). |
Magnetic Hold Downs |
N88-9-6 | 1 required for each Tee Section used. 15/8" (41mm) long. |
Fastener Kit | N88-9-7 | Fasteners, Allen Key, Nylon Thumb Screws, Contact Point. |
Carrying Case | N88-9-8 | Hard Sided Plastic Carrying Case for entire kit. |
Assembly
All Bridge type Blades (Main, Extender, End,&Slider) have two distinct sides, that are differentiated by the transverse mounting holes. On one side there is a clearance hole, while on the opposite side the hole is threaded ). When assembling, start the fasteners on the Thread Clearance Side of the Blades, so the fasteners can be properly tightened against the Extender Tee's. Do not tighten fasteners if an Extender Tee is not within the Slot area of a Blade.
When assembling the unit, press firmly (as illustrated) on the Extender T, and the Blade you are attaching it to, while tightening the 10-24x" Button Head Machine Screws with the 1/8" Allen Key. When assembled in this fashion, the overall length of the unit should have a straightness of approximately 0.015". When more accuracy is required, assemble the unit on a flatsurface.If the surface of the workpiece has an irregular surface (slight curve, distinctbend or hills and valleys), simply assemble the Bridging Bar, but do nottighten the fasteners. This will leave the Bridge loose and free to match thecontour of the workpiece. When the operator has contoured the assembledBridge, all the fasteners can be tightened. The operator should be mindfulthat this contouring assembly will be fine at a given point, however it will needto be checked when the Bridging Bar is repositioned.
Magnetic Hold Downs
Magnetic Hold Downs are intended for Scanning with a Bridging Pit Gauge, however they can be used on any of the Jr. Bridging Pit Gauge Group, with a diminished range of motion. Magnetic Hold Downs also provide the inspector with increased mobility, as he is not required to support the Bridging Pit Gauge. The following are instructions for the use, and using, the Magnetic Hold Down Blocks.
Magnetic Hold Down Blocks are designed to easily slide on the Extender Tee's, and are best put in place prior to assembly. With the Bridge assembled, and placed on the workpiece, the entire Bridging Pit Gauge can travel over a distance of about 9" (290mm). Longitudinal or position measurements of the Bridging Pit Gauge are taken off the Scales (imperial and metric divisions) that are fastened to the top of the Extender Tees.
BRIDGING PLUS
Pipeline integrity professionals go to great lengths to avoid unnecessary cut outs by evaluating the remaining strength of corroded pipe (RSTRENG). In some cases, the ability to perform longer scans, without resetting the position of the Magnetic Bridge is an asset. The Bridging Pit Gauge – Plus allows longitudinal scans of up to 24” (61cm).
The Bridging Pit Gauge goes beyond our Extended Reach Bridging Pit Gauges that are typically 4 to 6’ (1.2m to 1.8m) long. While this new Bridging Pit Gauge System isn’t for every inspector, it allows those with definite potential burst problems to provide an accurate result to avoid a catastrophic failure. A pipeline that isn’t moving petroleum products due to failure is not just losing money it is costing a lot more.
Name |
Part# |
Description |
Bridging |
N88-9 |
Main Blade, Imperial Dial Indicator, Connector Blade, 2-Extender Tees, End Blade, Slider Blade, Hardware, Extra Contact Point, and Carrying Case. |
Main Blade |
N88-9-1 |
Center and End Dial Indicator Mounting Positions, Cutaway Nose for next to welds. 5.5" (144mm) long. |
Connector Blade |
N88-9-2 |
Joins Tee Sections to increase length. 3.5" (90mm) long. |
End Blade |
N88-9-3 |
Mounts on end of Tee for extra contact. 1.5" (38mm) long. |
Slider Blade |
N88-9-4 |
Extra Point of Contact and doubles as an End Blade in Spanning Configuration. 1.5" (38mm) long. |
Extender Tee |
N88-9-5 |
2xExtends effective length of all models. 24" (305mm) long (Longer Tees are optional). |
Magnetic |
N88-9-6 |
4 required - 15/8" (41mm) long. |
Fastener Kit |
N88-9-7 |
Fasteners, Allen Key, Nylon Thumb Screws, Contact Point. |
Carrying Case |
N88-9-8 |
Hard Sided Plastic Carrying Case for entire kit. |