Swagelok P4T Series Quarter-Turn Plug Valve

Overview

The Swagelok P4T is a compact quarter-turn plug valve used for on-off isolation and forward-flow throttling in instrument tubing, sample lines, gas panels and utility connections. Swagelok describes its plug valves as offering low-torque operation in a simple design that provides positive shutoff of forward flow at pressures up to 3000 psig (206 bar). The Swagelok P4T has a one-piece body, a replaceable plug assembly, an O-ring seal to atmosphere and a straight-through flow path, and it is offered in 316 stainless steel and brass with end connections from 1/8 to 3/8 in. and 6 mm. The larger P6T series covers 3/8 and 1/2 in. and 8 to 12 mm sizes.

Seven Star LLC supplies Swagelok P4T plug valves and their handle, locking and panel-mount options to oil and gas, petrochemical, power, desalination and laboratory customers in Oman and the GCC. We help customers choose the body material, end connection and O-ring material, and we provide model selection support from Muscat.

Features of the Swagelok P4T

• Quarter-turn operation: 90 degrees of handle travel takes the valve from fully open to fully closed, with low operating torque.
• Straight-through flow path: minimizes pressure drop in the open position.
• Forward-flow throttling: the plug can be set at intermediate positions to regulate forward flow.
• Simple maintenance: one-piece body and replaceable plug assembly make the Swagelok P4T easy to clean and service.
• PTFE-coated O-rings: PTFE-coated fluorocarbon FKM O-rings are standard, with Kalrez, PTFE-coated Buna N, ethylene propylene and neoprene available.
• Polyetherimide handle: dark green is standard, with black, blue and red options.

Materials of Construction

In the stainless steel version the body is 316 SS to ASTM A479 and the plug is PTFE-coated 316 SS; in the brass version the body is brass to ASTM B16 with a PTFE-coated brass plug. Pins are 316 SS, the snap ring is PH 15-7 Mo stainless steel, and a silicone-based lubricant is used. Wetted materials are therefore the body, plug and O-rings, which should be checked for compatibility with the process fluid before a Swagelok P4T is specified.

Pressure-Temperature Ratings

Ratings are based on PTFE-coated FKM O-rings. A 316 stainless steel Swagelok P4T is rated 3000 psig (206 bar) from −10 to 200°F (−23 to 93°C), 2000 psig (137 bar) at 250°F (121°C) and 1000 psig (68.9 bar) from 300 to 400°F (148 to 204°C). A brass P4T is rated 3000 psig (206 bar) to 100°F (37°C), 2500 psig (172 bar) at 150°F (65°C), 2000 psig (137 bar) at 200°F (93°C), 1500 psig (103 bar) at 250°F (121°C), 1000 psig (68.9 bar) at 300 to 350°F, and 400 psig (27.5 bar) at 400°F (204°C). Swagelok notes that differential pressure is limited to 150 psig (10.3 bar) if reverse flow occurs, and that throttling in reverse flow may damage the O-ring, so the valve should be installed with the flow arrow in the normal flow direction.

Flow Data and Sizes

The Swagelok P4T has a 0.172 in. (4.4 mm) orifice in most sizes and 0.093 in. (2.3 mm) in the 1/8 in. tube fitting version. Swagelok lists a flow coefficient of 1.6 for the 1/4 in. and 6 mm tube fitting versions, 1.1 for the 3/8 in. tube fitting P4T, 0.10 for the 1/8 in. tube fitting version, and between 0.9 and 1.2 for the NPT and ISO threaded versions. At a 10 psi pressure drop to atmosphere, a 1/4 in. tube fitting valve passes about 18 std ft3/min of air or 5.1 U.S. gal/min of water, according to the catalog flow table. Every Swagelok plug valve is factory tested for shutoff at 600 psig (41.3 bar) and is cleaned and packaged to Swagelok SC-10.

Typical Swagelok P4T ordering numbers include SS-2P4T and SS-4P4T for 1/8 and 1/4 in. tube fittings, SS-6P4T for 3/8 in., SS-6P4T-MM for 6 mm, SS-4P4T4 for 1/4 in. female NPT, SS-4P4T2 for 1/4 in. male NPT, SS-4P4T1 for male NPT by tube fitting, SS-4P4T5 for male by female NPT, and SS-4P4T4-RT for 1/4 in. female ISO threads. Brass versions replace SS with B.

Options and Accessories

• Downstream vent: vented plug and body release downstream pressure to atmosphere when the valve is closed (150 psig maximum operating pressure); ordered by replacing T with V, for example SS-2P4V.
• Metal handles: stainless steel (-M1) or aluminum (-M2); removing the roll pin means the valve can only be operated with a wrench.
• Locking handles: the -LD option or field kit SS-5LDK-P4T-GR locks the valve open or closed and meets OSHA lockout/tagout standard 29 CFR 1910.147.
• Panel mounting: the valve can be panel mounted using the hardware listed in the catalog.

Applications

Common uses of the Swagelok P4T include analyzer sample panel isolation, purge and vent lines, instrument air and nitrogen headers, calibration gas manifolds, lubrication and hydraulic test points, and laboratory gas supply lines. On analyzer and sampling skids, it is often installed together with Swagelok SS-43GS4 40G series ball valves for higher-flow isolation, SS-1RS4 needle valves for fine metering, and QC series quick-connects for portable connections.

Selection Tips (General Guidance)

These are general engineering points rather than Swagelok data. Use stainless steel bodies for corrosive, sour or hygienic services and brass for clean air, water and inert gas where cost is a priority. Do not use a Swagelok P4T where reverse flow at high differential pressure can occur. Choose the O-ring elastomer to suit the fluid and temperature, for example ethylene propylene for some water and steam condensate duties, and FKM for most hydrocarbons. For lines that must be secured closed during maintenance, specify the locking handle option.

Technical Specifications

How to Order

To order the Swagelok P4T, send Seven Star LLC the fluid, pressure and temperature, body material, end connection and any handle, vent or locking option you need. Our Muscat team will confirm the ordering number against the Swagelok catalog and prepare a formal quotation. The Swagelok P4T catalog can be downloaded from this page, and we provide model selection support from Muscat across Oman and the GCC.