Mounting
The PT 275 and PT 750 transmitters can be mounted in a steel mandrel pig body, foam pigs, or be towed behind a pig using spacing or wear discs. A mounting plate adaptor is required for proper mounting of the transmitter. When properly installed, the battery section of the transmitter is enclosed in the pig body and the electronics section of the transmitter is exposed. When towed behind a pig, it is recommended that the transmitter be installed in a medium or high density Polly-Pig with criss-cross type spirals of polyurethane coating. For mounting in a cavity or mandrel the minimum hole diameter is:
| PT 107 | 1 1/2" |
| PT 275 | 3 3/8" |
| PT 750 | 3 1/2" |
Operation
For normal tracking or pig signaler operation the wand is kept parallel to the pipe. For pinpointing the pig, the wand is held perpendicular or at 90º to the pipe or transmitter. The depth (distance to the transmitter) can be determined by triangulation. The receiver will occasionally pick up some outside interference that can be recognized with a minimum amount of operating experience. Common causes of outside interference are:
- Automotive electronic ignitions
- Keying two-way radios
- Large belt buckles or key rings
- Some electronic watches
- Large electrical transmission equipment
| PT 107 | One 3V Lithium battery. Maximum signal strength is 60+ hours. |
| PT 275 | Four "AA" batteries. Maximum signal strength is 200+ hours. |
| PT 750 | Eight "C" batteries. Maximum signal strength is 500+ hours. |
| PTR (Receiver) | Two 9 volt batteries. 50 hours of continuous operation. |
|
|
Signal
Strength of Pick-Up Range |
| Underground |
Above
Ground (Free Air) |
| PT
107 |
8
Feet |
20-25
Feet |
| PT
275 |
15
Feet |
65-70
Feet |
| PT
750 |
25-30
Feet |
100
Feet |
|
Model |
Signal
Strength of Pick-Up Range |
| Underground |
Above
Ground (Free Air) |
| PT
107 |
8
Feet |
20-25
Feet |
| PT
275 |
15
Feet |
65-70
Feet |
| PT
750 |
25-30
Feet |
100
Feet |
The transmitters can withstand operating pressures of:
| PT 107 | 1000 PSI |
| PT 275 | 2000 PSI |
| PT 750 | 3000 PSI |
System Specifications
| System |
Size
(Inches) |
Batteries |
Hours
of Signal |
Model
2 System
For 4" to 6" Pipelines
Includes: PT 107 Transmitter, receiver (PTR), pick-up
wand, shoulder strap, wrench, batteries, and durable shipping
case. |
Length:
6 1/2"
Diameter
1 1/4" |
1
ea.
3V Lithium |
60 |
Model
4 System
For 8" to 12" Pipelines
Includes: PT 275 Transmitter, receiver (PTR), pick-up
wand, shoulder strap, wrench, batteries, and durable shipping
case. |
Length:
9 1/2"
Diameter:
3" |
4
ea.
"AA" Type |
200 |
Model
12 System
For 12" & Larger Pipelines
Includes: PT 750 Transmitter, receiver (PTR), pick-up
wand, shoulder strap, wrench, batteries, and durable shipping
case. |
Length:
16"
Diameter:
3 1/8" |
8
ea.
"C" Type |
500 |
Recommended Procedures
Using a Transmitter Pig for Location of Trouble Spots
It is important to identify and locate trouble spots in a pipeline. This can be accomplished by running a pig with an electronic transmitter. A few precautions should be followed prior to introducing the transmitter pig into the line.
A. Always make sure the line has flow capabilities. This is easily accomplished by running a YBS (2 Ib/ft3 density swab) to prove the line. Unless the line is severely restricted, the YBS should come out at the discharge end of the line. If the problem is construction debris, the debris could restrict the swab from traveling the full length of the pipeline. If this happens, put the transmitter pig into the pipeline to locate the stuck pig.
B. If the pipeline in question has never been pigged, or has only been pigged intermittently, Girard recommends using the progressive pigging method to clean the pipeline.
C. If the pipeline has been pigged on a routine basis, a YBS should still be run first. This will determine if any changes have occurred in the pipeline which would cause a problem.
