Torque Values

Based on Zero Leak Gold® Plug Testing at the Fluid Power Institute, located at the Milwaukee School of Engineering

EPCO commissioned an independent study to determine the estimated torque values for Zero-Leak Gold Plugs, which was conducted by the FPI. The FPI reported that the ZLG plug torque values were approximately 60% of their old style, O-ring only, SAE J514 ORB plug counterparts. The torque data tables provided below are intended to serve as a reference point for establishing torque values for specific applications.

See the Torque Values Tables

Torque Tips

Determining Torque Values for Specific Applications

The torque values for the Zero-Leak Gold Plugs in the FPI test were the result of the findings reported at the conclusion of the specific test performed. EPCO provides the torque data tables below as a reference point for establishing application specific torque values for ZLGP.

As it is known, torque values can vary widely depending on vibration, pressure spikes, cycling, temperature changes, etc. Therefore, EPCO suggests the installation torque values for specific applications be established by using the torque values in the FPI test as a base value.

For SAE plug sizes covered in the FPI test report:

The installation torque values in the test are approximately 60% of the torque value for like sizes of SAE J514 plugs. Start with the FPI torque values and cycle test the application. Should a failure occur, stop the test, clean all components, increase the torque value by 5% and repeat the test. This procedure can be repeated until an acceptable torque value is established.

For SAE plug sizes NOT covered in the FPI test report:

The installation torque values in the test are approximately 60% of the torque value for like sizes of SAE J514 plugs. Start with 60% of the SAE torque values for J514 plugs and cycle test the application. Should a failure occur, stop the test, clean all components, increase the torque value by 5% and repeat the test. This procedure can be repeated until an acceptable torque value is established.

For Metric Plug Sizes

EPCO does not have validated torque values for the metric style ZLGP. The torque values for the SAE style Zero-Leak Gold Plugs in the Fluid Power Institute were the result of the findings reported at the conclusion of the specific test performed. EPCO provides the torque data as a reference point for establishing application specific torque values for ZLGP. As you know, torque values can vary widely depending on vibration, pressure spikes, cycling, temperature changes, etc. Therefore, EPCO suggests the installation torque values for specific applications be established by using the torque values in the FPI test as a base value. The installation torque values in the test are approximately 60% of the torque value for like sizes of SAE J514 plugs. It may be possible to establish a metric torque value by identifying the SAE size plug which is closest to the metric size plug in question. Start with the FPI torque value or 60% of the torque values for that SAE plug and cycle test the application. See the Torque Values tables below. Should a failure occur, stop the test, clean all components, increase the torque value by 5% and repeat the test. This procedure can be repeated until an acceptable torque value is established.

Table 1: EPCO Zero-Leak Gold Plug Testing Torque Values

Report Torque
Values (ft-lbs) by Material
SAE & Zero-Leak Gold Plug Size Ductile Iron Aluminum SAE Torque Value Percentage of SAE stated Torque
-2 2 2 3 ± .4 58.8%
-3 3 3 5.6 ± .4 57.6%
-4 7 7 8.9 ± .8 72.0%
-5 9 9 12 ± 1.6 66.1%
-6 11 11 18.7 ± 2 58.8%
-8 28 28 35 ± 4 71.7%
-10 46 46 55 ± 4 77.9%
-12 51 51 75 ± 4

64.5%

Table 2:

EPCO Zero-Leak Gold Plugs Proof and Burst Pressure Testing

Block
Number		 Proof Test Burst Test
Pressure (psi) Fitting sizes
on Manifold		 TIME AT
PRESSURE		 Burst
Pressure (psi)		 Mode of
Failure
Aluminum Ductile Iron
SAE
1 6000 — 2,3,4 120 sec 21,769 No failure
2 6000 — 5,6,8 120 sec 23,111 No failure
3 6000 — 10,12 120 sec 23,339 Manifold thread failure (SAE #10 Port)
4 — 10,000 2,3,4 120 sec 21,699 No failure
5 — 10,000 5,6,8 120 sec 26,453 No failure
6 — 10,000 10,12 120 sec 22,567 No failure

Table 3: Removal Torque

Zero-Leak Gold Plug Size Aluminum Average Removal Torque
(ft-lbs)		 Ductile Iron Average Removal Torque
(ft-lbs)
Initial Torque
(ft-lbs)		 Removal Torque
(ft-lbs)		 Initial Torque
(ft-lbs)		 Removal Torque
(ft-lbs)
2
2
2		 2
2
2		 3.75
6.5
5.25		 —
5.2
—		 2
2
2		 3
2.75
6.25		 —
4.0
—
3
3
3		 3
3
3		 4
6.25
6.25		 —
5.5
—		 3
3
3		 4.25
4.25
4.5		 —
4.3
4
4
4		 7
7
7		 28.5
31.5
27		 —
29.0
—		 7
7
7		 7.25
6.75
11.75		 —
8.6
—
5
5
5		 9
9
9		 27.5
28
31		 —
28.8
—		 9
9
9		 11
11.5
10.75		 —
11.1
—
6
6
6		 11
11
11		 34.25
34
31		 —
33.1
—		 11
11
11		 22.5
12
14		 —
16.2
—
8
8
8		 28
28
28		 80
75
75		 —
76.7
—		 28
28
28		 40
31.5
29		 —
33.5
—
10
10
10		 45
45
45		 115
125
120		 —
120.0
—		 45
45
45		 135
95
125		 —
118.3
—
12
12
12		 51
51
51		 155
160
185		 —
166.7
—		 51
51
51		 60
85
85		 —
76.7
—