SN - Limited Overhead Clearance Replacement Nut

SN Series Clamp Overview

The SN Series clamp was originally specified to overcome tight overhead restrictions. The SN Series ClampNut is used with a slim-line hydraulic cassette tool. The low profile SN Series and its equally low profile tools make them an ideal choice for applications where traditional fastening methods simply won’t fit.

The tool operates beside the clamp and needs just over one clamp height above the clamp or stud in order to be positioned. The through bolt design is also useful in situations where high stud extensions make standard nuts and tooling impractical. The SN Series does require sufficient radial clearance since the tool has a footprint larger than that of the clamp. The SN Series clamps are typically specified when overhead obstructions are present.

back to menu

SN Series Clamp Features & Benefits

BENEFITS

• Reaction free bolt tensioning
• Pure tensile loads
• 100% elimination of galling on flange and stud surfaces
• Highest bolt tension accuracy and reliability available

FEATURES

• The SN Series ClampNut is used with a slim-line hydraulic cassette tool.
• Lowest profile allows fit in very tight applications
• Pass through design and tooling allows for unlimited stud protrusion
• Low, Standard, Medium & High temperature ratings available
• All thread forms available

back to menu

s

SN Series Clamp Specifications

1. Identify Blank Size from table below. (Cross reference this number from the row with the proper Nominal Stud Size)
2. Verify that the Outside Diameter for this Blank Size will not interfere with adjacent nuts or other application constraints. (Such as a small counter bore)
3. Verify that the Max Load and Max Stroke are sufficient for the application.
4. Verify that the stud protrusion is not too tall. Standard TN Series clamps cannot handle studs that protrude more than the Nominal Stud Size. (This can be increased by 10% if an inverted drive is not necessary)
5. Verify that there is sufficient overhead clearance for access with tooling.
6. Fill out the part number information on the adjacent page.

BLANK SIZE This is the basic body size for the CN Series clamp. Any desired thread up to the Nominal Stud Size can be cut into each Blank Size. SIZE CODE Size Code is the JETYD code used to indicate the Nominal Stud Size. The first digit signifies the whole number of inches. The second two digits signify the number of 1/16 of an inch. (108 = 1” + 8/16 = 1½”) NOMINAL STUD SIZE This is the largest stud that will fit a particular Blank Size. All TN Series clamp blanks can be specified with threads smaller than the Nominal Stud Size. HEIGHT This is the overall height of the standard TN Series clamp for this Blank Size. Tooling will require additional overhead space. This is not the Height of the stud protrusion. Consult with a JETYD Applications Engineer when custom taller clamps are required. MAX STROKE TN Series clamps have maximum stroke lengths that are limited by the height of the splined washer. More stroke may be needed to accommodate gasket compression or an extraordinarily long joint length. Consult with a JETYD Applications Engineer for special extended stroke clamps. MAX LOAD This is the recommended maximum target load for each fastener on the application. This load is conservative as it allows margin for removal. It is based on 80% yield for ASTM A193 B7-B16 & 8TPI bolt material for the listed Nominal Stud Size. Consult with a JETYD Applications Engineer when higher loads are required.

BLANK SIZE	SIZE CODE	NOMINAL STUD SIZE		OUTSIDE DIAMETER (in)	HEIGHT (in)	MAX STROKE (in)	MAX LOAD (in)
		INCH	METRIC
01	14	7/8	M20	1.400	1.313	0.197	32,781
02	100	1	M24	1.600	1.500	0.225	44,475
03	102	1 1/8	M27	1.800	1.688	0.254	58,036
04	104	1 ¼	M30	2.000	1.875	0.281	73,390
05	106	1 3/8	M33	2.200	2.063	0.310	90,626
06	108	1 ½	M36/39	2.400	2.250	0.338	109,662
07	110	1 5/8	M42*	2.600	2.438	0.366	130,830
08	112	1 ¾	M45	3.800	2.625	0.394	152,880
09	114	1 7/8	M48	3.000	2.813	0.422	177,135
10	200	2	M52	3.200	3.000	0.450	203,595
11**	204	2 ¼	M56	3.600	3.375	0.506	261,660
12	208	2 ½	M64	4.000	3.750	0.563	326,340
13	212	2 ¾	M70	4.400	4.125	0.619	361,095
14	-	-	M72	4.535	4.253	0.638	395,675
15	300	3	M76	4.800	4.500	0.675	432,915
16	-	-	M80	5.040	4.725	0.709	447,346
17	304	3 ¼	-	5.200	4.875	0.731	511,385
18	308	3 ½	M90	5.600	5.250	0.788	595,840
19	312	3 ¾	M95	6.000	5.625	0.844	687,610
20	400	4	M100	6.400	6.000	0.900	785,365
21	404	4 ¼	M110	6.800	6.375	0.956	796,110
22	408	4 ½	M115	7.200	6.750	1.013	898,450
23	412	4 ¾	M120	7.600	7.125	1.069	999,600
24	500	5	M125	8.000	7.500	1.125	1,112,650
25	504	5 ¼	M130	8.400	7.875	1.181	1,231,650
26	508	5 ½	M140	8.800	8.250	11.238	1,350,650

back to menu

SN Series Clamp Facts & Information

Materials

TN Series material selection is based on the service temperature rating of the clamp. Please see the Clamp Service Temperature section of the JETYD catalog for a detailed specification on the materials used for each component of the clamp.

Application Tips

Measurement of the thread pitch is the most error prone portion of clamp specification. The easiest way to measure pitch is with a pitch gauge. Alternatively please provide JETYD with a sample of the stud.

Special coatings can cause dimensional variations on studs and nuts, i.e. Galvanized studs often have a coating build up that effectively changes the thread size. If the application studs have coatings, special care should be taken to determine the actual thread size. A standard UN nut will not fit a standard UN stud thread if a thick coating is applied. In these situations it will typically be best to supply JETYD with a sample stud.

Available Drives

Click here to see the Clamp Drive section.

Load Charts

All TN Series clamps are available with a Load Chart. Load Charts provide data points showing the tool’s hydraulic pressure vs. the bolt load that will be attained. A load chart can be created for any tool with any clamp.

Specials

When components fall outside of the boundaries of our standard parts’ numbering system, they become Specials. The following list exemplifies some of the variations that could make your clamp specification a Special:

• Modified or non standard thread sizes such as those for oversize studs
• Extended or shortened clamp length requirements
• Extended stroke requirements
• Special coating requirements such as galvanizing or Xylan
• Non-standard materials, testing or certification requirements

Specials will be assigned a special part number. Please contact a JETYD application engineer when specifying non-standard clamps.

back to menu

SN Series Clamp Applications

Common SN Series applications include:

• crosshead
• turbines casing
• compressors
• valves and pumps - spot space
• boiler feed pump
• boiler circulation pumps
• pocket bolts
• blade rings
• steam valve, stop valve, throttle valve
• couplings
• anchor bolts

Click on an image for a larger view

back to menu

SN Series Clamp Demonstration Video

back to menu