John Guest Products Technical Specifications
Working Pressure and Temperature Range
Super Speedfit fittings are suitable for the following pressures and temperatures.
5/32" to 5/16"
(4mm to 8mm)
3/8" to 1/2"
(10mm to 22mm)
230 psi
(16 Bar)
150 psi
(10 Bar)
 230 psi
(16 Bar) 
150 psi
(10 Bar)
 230 psi
(16 Bar) 
150 psi
(10 Bar)
150 psi
(10 Bar)
100 psi
(7 Bar)
Also suitable for vacuum.

Depending on the tube used, under certain conditions fittings may be used at higher pressures and temperatures. Please refer to our Customer Services Department for guidance.

Note 1 Bar = 14.5 PSIG.
Tube Types
Plastic Tube — Polyethylene, nylon, and polyurethane conforming to the tolerances shown below. For soft tubing or thin wall tube we recommend the use of tube inserts.

Braided Tube — Use of Tube to Hose Stems is essential when using braided tube or hose. Use of clamps to retain braided tube on barbs is recommended.

Metal Tube (soft) — Brass, copper, or mild steel conforming to the tolerances below.

Metal Tube (hard) — We do not recommend Super Speedfit fittings for hard metal tubes or chrome plated tubes.

For stainless steel and other polished metal tubes we recommend the use of Superseal fittings.
Click here for more details.

It is essential that outside diameters be free from score marks and that the tube be deburred before inserting the fitting.
Tube Tolerances
Super Speedfit fittings are offered for tubes with outside diameters to the following tolerances.
5/32 to 3/16 1/4 to 1/2
+0.001 to
+0.001 to
4 to 5 6 to 22
+0.05 to
+0.05 to
Collet Covers
Are available as additional security against removal of the tube or to provide a simple means of color coding. The cover is offered in a range of six colors (black, red, yellow, gray, blue, green). Please refer to our Customer Services Department.
Food Quality
All fittings are produced in Food and Drug Administration (FDA) approved materials and are therefore recommended for food quality applications.

The wetted surfaces of John Guest PI, PM, SI, CI, and PP plastic fittings, PPSV and ASVPP valves, and LLDPE tubing are in compliance with FDA requirements for direct contact with food as detailed in 21CFR part 177.2470 for the body and 177.2600 for the O-ring.

NSF International Standard 51 and 61.
Installation and System Testing
Fittings and tube should be kept clean and undamaged before use.

All tube and fittings installations must be pressure tested after installation to ensure system integrity before handing over to the final user. Refer to “How to make a connection.”
For use with chemicals or other potentially aggressive liquids, please refer to our Customer Services Department.

Super Speedfit fittings are not recommended for use with explosive gases, petroleum spirits, and other fuels or for central heating systems.
Maximum Torque Values for Threaded Fittings
Do not overtighten plastic threaded fittings as this could cause undue stress and eventual failure. Maximum recommended torque figures are shown below.
1/8" to 1/4" 3/8" to 1/2" 3/4"
1.0 ft. lbs.
(1.5 Nm)
2.2 ft. lbs.
(3.0 Nm)
2.9 ft. lbs.
(4.0 Nm)
1. Manufacturer recommends that OEM customers consider replacing threaded ports with the more modern Cartridge Systems.
2. It is recommended that all installations are checked prior to use to determine that a seal has been made.
3. The maximum torque figures quoted for use with Speedfit fittings are dependent on the mating thread conforming to the relevant US, British, or International thread standard.
Maintenance and Replacement Intervals
Generally, little maintenance is required, but as a minimum we recommend routine visual inspection. Frequency of visual inspection will depend on severity of application and risk of failure. If after visual inspection products appear damaged, cracked, charred, discolored, heat distorted, or corroded, they should be replaced. Any product that is or appears to be leaking should be replaced.

Product life is affected by the severity of the application, the hostility of the working environment, and contact with aggressive chemicals or liquids. It is therefore important that specific replacement intervals be considered by specifiers/users/customers based on previous service life or when failure could result in unacceptable downtime, damage, or injury risk.
Cleaning and Sanitizing
Our advice to customers is to use cleaners and sanitizing agents that are above pH 4 and low in hypochlorite level.

Acetal fittings and parts that are cleaned and/or sanitized should be rinsed immediately with copious amounts of clean tap water to remove all traces of the cleaners. ECOLAB Oasis 133 is recommended as a suitable external cleaner for acetal products.

Polypropylene fittings offer greater resistance to aggressive chemicals than acetal fittings. Polypropylene does not have the same mechanical properties as acetal.

ECOLAB Oasis 133 is recommended as a suitable external cleaner for John Guest products.
Side Load
Fittings should not be subject to excessive side loads and they should not be used as support brackets. Tubing and fittings should be adequately supported to prevent excessive side loading.
While we give a warranty against defects in manufacture or materials, it is the responsibility of the specifier to ensure that fittings and related products are suitable for their application. The installation must be carried out correctly in accordance with our recommendations, complying with recognized codes of practice and relevant national standards, and be properly maintained. Please refer to our terms and conditions of sale.
Safe Water Technologies, Inc.
996 Bluff City Boulevard
Elgin, IL 60120 USA
Telephone: +1.847.888.6900
Facsimile: +1.847.888.6924

Last Updated: January 3, 2014