Pipe Locators

Accuracy is the foremost concern of surveyors. You won’t compromise on accuracy for a total station or RTK kit, so why compromise on accuracy when it comes to a pipe locator? For this reason, Bench Mark carries pipe locators manufactured in Japan. Pipe locators consist of a receiver and an amplifier or transmitter. All pipe locators sold by Bench Mark are capable of inductive operation, where a an electric current is induced in the pipe by a magnetic field; conductive operation, where a lead is connected directly to the utility; and clamp, which is inductive operation facilitated by a coil clamped around the pipe to be located. Inductive mode is the most simple mode of utility locating, as long as at least one location is known. Simply place the transmitter on the known point, and turn it on, then sweep your receiver at least 50 feet away from the transmitter. Once a second location is verified leapfrog the transmitter to the new location and trace back to your original point, verifying the path of the pipe. If you are in a “congested” area or need to locate a pipe for a long distance, you may find conductive operation to be your best bet. In this case, you are using the pipe locator’s transmitter to broadcast a signal through the utility with one wire; meanwhile a ground stake is connected to the transmitter with the other wire. This ground stake is connected as far away from the utility as possible, orthogonal to the suspected path of the pipe. This creates a circuit, the signal travels down the pipe, and is then carried through the grand back to the ground stake. Bench Mark pipe locators are capable of transmitting at 3 watts in this mode of operation. Once the transmitter is operating, the pipe locator receiver is then swept (in a vertical orientation) across the suspected path of the pipe, registering the precise location of the utility through either peak or null mode. All Bench Mark pipe locators are capable of providing a highly accurate depth reading, come with a soft case and warranty, and are backed by a 3 year manufacturer warranty.

Best Practices

When using a pipe locator, be careful to avoid the sweeping technique that would use with a magnetic locator (pin finder), when sweeping the pipe locator, ensure it remains perpendicular to the ground. Make sure you familiarize yourself with the pipe locator that you purchase, they are equipped with different frequencies and power outputs. These frequencies are optimized for use in specific situations, and use of the correct frequency will improve both your range and the accuracy of your readings. Also remain current with relevant safety procedures, different methods of use with a pipe locator carry an inherent risk, especially when locating buried power cables.

All Materials Locator

All Materials Locator (AML) is the most innovative underground material locator in production today. Recipient of the Contractors’ top 50 new products 2013  award, the AML uses high frequency radio waves to detect sub surface objects, which means you are no longer limited to detecting metal. Used as a Pipe Locator, the AML can detect PVC and PE pipe with ease, and using it’s ultra high frequency ground penetrating radio waves, is able to detect any material with an edge, allowing you to dig without worry.

Leak Detectors

In addition to the full range of Pipe Locators, Bench Mark offers the LD-8, LD-12, LD-15 and LD-18 leak detectors. Manufactured in Japan, these leak detectors represent the cutting edge of audio leak detection, offering intermittent noise reduction and visual readouts.


(2.1) LD-18 Leak Detector

Product Details
  • 900 V/G Sensitivity or Higher (at 400Hz)
  • Low Filters: Off 100Hz, 200Hz, 400 Hz
  • High Filters: 400Hz, 600Hz, 800Hz, 1200Hz, 2200Hz
  • Notch Filters Off, 50Hz, 60Hz
  • 24 Hour Battery Life
  • 50 to 2200 Hz frequency range
Package Includes:
  • Amplifier with LCD Display
  • Padded case for Amplifier
  • 40 inches Belt
  • Ground Microphone and Handswitch
  • Magnet base and nutdriver
  • Pelican Case
  • Stereo Headphones
  • PC Software and USB Cable

(2.2) LD-15 Leak Detector

Product Details
  • Amplification : 56 dB 
  • Filter Ranges : 1) High Range 30 Hz to 5000 Hz
  • 2) Low Range 30 Hz to 800 Hz
  • 3) Notch Filter 150 Hz, 180 Hz
  • Power : 4 C dry cell batteries
Package Includes:
  • Amplifier with Meter Display and Filter Controls
  • Padded Case and Standard Belt (40 inches)
  • High Sensitivity Sensor and Cable
  • Base Plate for Listening on Street Surfaces
  • Aviation-Grade Stereo Headphones
  • Heavy-Duty ABS Plastic Carrying Case

(2.3) LD-12 Leak Detector

Product Details
  • Input Impedance : 50k ohms
  • Output Impedance : 15 ohms
  • Amplification : 62 dB +/- 3dB
  • Frequency Range : 1) 100Hz to 1200Hz(13 dB) with Filter-Thru OFF
  •  15Hz to 30,000Hz (13 dB) with Filter-Thru ON
Package Includes:
  • Amplifier with Meter Display and Filter Controls
  • Ground Microphone and Handswitch
  • Aviation-Grade Stereo Headphones
  • Heavy-Duty ABS Plastic Carrying Case
  • Magnet Base
  • 3-Section Contact Rod
  • Nut Driver (to remove base)
  • Instruction Manual (not shown)