Series-PTGD

Supported Applications

The Dwyer Series PTGD Differential Pressure Piston-Type Gage is designed to measure pressure drop across filters, strainers, pump performance testing, and heat exchanger pressure drop monitoring. The instrument measures differential pressure in compatible gases and liquids.

Operating Conditions & Performance

The series features a piston-sensing element with full-scale accuracies of ±2% FS ascending. It is rated for an ambient temperature limit of 176°F (80°C). Over-range protection varies by construction material: the aluminum body supports pressure limits up to 3000 psi (206 bar), while the stainless steel body supports up to 6000 psi (400 bar) or 6000 psi (413 bar) depending on the source document. The gage can be mounted in any position.

Configuration Options

The Series PTGD is available with configurable wetted materials, sizes, and process connections to suit specific installation requirements.

• Housing & Wetted Materials: Gage body and piston are offered in Aluminum or 316 SS. The spring is constructed of 302 SS. Seals include Buna-N (standard), PTFE, or Ceramic options. The dial case utilizes Nylon 6 with 30% glass fill.
• Sizes: Available in 2.5" (63 mm) and 4.5" (115 mm) diameters.
• Process Connections: Standard connections are 1/4" female NPT end connections. Back or bottom connection styles with 1/4" female NPT are available. All styles can be configured with 1/4" BSP threads.
• Ranges & Scales: The series supports various differential pressure ranges including psid, bar, kg/cm², and kPa scales (e.g., 0-5 to 0-150 psid). A SQRT scale option is available for flow applications such as 0-600 gpm.
• Accessories: Options include a Universal pipe mounting kit (A-627) for 2" diameter pipe and NIST traceable pressure calibration certificates (NISTCAL-PG1).

Key Product Differences

The series distinguishes between aluminum and stainless steel constructions, which directly impacts the maximum over-range protection rating. The model number structure follows the format PTGD - [WETTED PARTS] - [SIZE] - [RANGE] - [VARIANT 2] - [OPTIONS]. For example, a specific configuration may be denoted as PTGD-A-A-02-A-PY.

Installation orientation recommendations vary by media: for liquid service, the instrument should be mounted below process connections to allow self-bleeding; for gas service, it should be mounted above to facilitate self-draining. If the process contains particulates, a 'pigtail' loop or drop leg is recommended to minimize migration into the instrument.