ASTM A320 L7 Combination Studs Combo Studs

ASTM A320/A320M L7 Combination Studs

Standard: According to drawing

Inch Size: 1/4”-2.1/2” with various lengths

Metric Size: M6-M64 with various lengths

Other Available Grade:

ASTM A193/A193M B7, B7M, B16 B8 Class 1 & 2, B8M Class 1 & 2,

ASTM A320/A320M L7, L7M, L43, B8 Class 1 & 2, B8M Class 1 & 2, and so on.

Finish: Plain, Black Oxide, Zinc Plated, Zinc Nickel Plated, Cadmium Plated, PTFE etc.

Packing: Bulk about 25 kgs each carton, 36 cartons each pallet

Advantage: High Quality and Strict Quality Control, Competitive Price,Timely Delivery; Technical Support, Supply Test Reports

Please feel free to contact us for more details.

ASTM A320

Scope Originally approved in 1948, the ASTM A320 specification covers alloy steel and stainless steel bolting materials for low temperature service. This standard covers rolled, forged, or strain hardened bars, bolts, screws, studs, and stud bolts used for pressure vessels, valves, flanges, and fittings. Like the ASTM A193 specification, unless otherwise specified, the 8UN thread series is specified on fastener larger than 1” in diameter. Below is a basic summary of a few of the common grades within the ASTM A320 specification. A number of other less common grades of ASTM A320 exist, but not covered in the description below.
Grades
L7 Alloy steel AISI 4140/4142 Quenched and tempered
L43 Alloy steel AISI 4340 Quenched and tempered
B8 Class 1 Stainless steel AISI 304, carbide solution treated
B8M Class 1 Stainless steel AISI 316, carbide solution treated
B8 Class 2 Stainless steel AISI 304, carbide solution treated, strain hardened
B8M Class 2 Stainless steel AISI 316, carbide solution treated, strain hardened
Mechanical Properties
Grade Size Tensile, ksi, min Yield, ksi, min Charpy Impact
20-ft-lbf @ temp
Elong, %, min RA, %, min
L7 Up to 21/2 125 105 -150° F 16 50
L43 Up to 4 125 105 -150° F 16 50
B8
Class 1
All 75 30 N/A 30 50
B8M
Class 1
All 75 30 N/A 30 50
B8
Class 2
Up to 3/4 125 100 N/A 12 35
7/8 - 1 115 80 N/A 15 35
11/8 - 11/4 105 65 N/A 20 35
13/8 - 11/2 100 50 N/A 28 45
B8M
Class 2
Up to 3/4 110 95 N/A 15 45
7/8 - 1 100 80 N/A 20 45
11/8 - 11/4 95 65 N/A 25 45
13/8 - 11/2 90 50 N/A 30 45
Recommended Nuts and Washers
Grade Nuts Washers
L7 A194 Grade 4 or 7 F436
L43 A194 Grade 4 or 7 F436
B8 Class 1 A194 Grade 8 SS304
B8M Class 1 A194 Grade 8M SS316
B8 Class 2 A194 Grade 8, strain hardened SS304
B8M Class 2 A194 Grade 8M, strain hardened SS316

Testing Lab

Workshop

Warehouse


  • ASTM A320 L7 Combination Studs Combo Studs Related Video:



    Hey y’all! After mulling a metric butt-ton of videos, sound clips and forums on this topic, I decided to go ahead and finish my upgrades on my Strat with a Brass Sustain Block and Graphtech saddles & do my own video showing my findings.

    Let your ears hear it for yourself. I wanted to hear NOTHING but the changes on the guitar, so I changed none of the recording settings, I put the same strings back on the guitar, before disassembly I noted the string heights and setup with a dial indicator, and set it back up within +/- .002″. I think this is as close as comparing apples to apples as one can get.

    I didn’t want any room reflections or anything else get in the way, so I plugged direct into an Eleven Rack running the 64 Vibro Clean sim stereo straight into Logic Pro X. Knowing the differences would be subtle, i opted to do a clean tone so not to bury the changes in gain. But to keep it ‘real world’, knowing most people run a bit of chorus, delay and or reverb, I did include those effects.

    Here is my line of thought on why I did this the way I did it.
    a) it seems most people talked about the changes affecting the notes ‘attack’ and ‘sustain’, therefore I chose to do a clean-tone with arpeggiated chords and a ringing chord to follow.
    b) It drove me crazy with the ‘before and after’ sounds being so far apart, so I cut and pasted this together so it was “bridge pickup-zink and stamped steel” followed by “bridge pickup – brass and Graphtech”, then I moved on to position 2, 3, 4 and lastly 5.
    c) Again, i wanted this to be a straight forward apple to apple comparison, so I touched NOTHING on the settings from the 2 takes.

    Here is what I found.
    a) The difference is very subtle. In many cases, because I had the tone controls kind of dialed in for the zink and stamped steel, you may think that combination sounds “better”, but hear me out before you make that decision.
    b) The attack of the notes are just a tad more compressed. I actually didn’t fully grasp that until i went back and looked at the wave forms when i was editing the audio. There is not as much spike overall on the initial attack. That is not to say that there are and will be inconsistencies due to the human factor applying the pick angle and attack.
    b) its not so much that the sustain is MORE … if you are familiar with audio editing, and applying fade outs, it changes the slope of the fade (decay) … it doesn’t drop as far as fast right off the bat. Again, this became more apparent after I started editing the audio and was LOOKING at the wave shapes.
    c) after spending a couple hours playing with it, i did notice ONE thing that was more apparent .. and it took me a while to catch this. I set my Strat up with the bridge sitting on the deck (which people STILL said you WOULD hear a difference in TONE .. yeah, not so much) … BUT .. when using the Trem, when you bring that bridge off the deck, it did not have the tonal difference AS much … thats a good thing! But, it took me a while to catch that. Again, it isn’t huge, but its there!
    d) the guitar is a little more resonant to play unplugged, it does feel a little more lively in hand and with the brass being a good 30% heavier than the zink, it gives the weight and balance a nice center point.
    e) The more i play it, I do hear that the individual notes do ring more balanced within a chord.

    So, with that being said … in conclusion after a couple hours playing and tweaking, are the differences worth it? I find that dialing in sweet spots a little easier. After tweaking settings, you can find better, sweeter tones within your amps dials. It gives you more useable range to play with. It has me wondering now, if all the upgrades i did previous to these last 2 maybe did not let me see as BIG as a difference as I thought i would. Time will tell … maybe I’ll go back to stock, and start doing videos one mod at a time …

    The guitar: 2008 Fender Stratocaster Std (Mexico) 48th St Special Edition in Graffiti Yellow.

    The Mods: Schaller Locking Tuners, Roller String Tree, Graphtech nut, Floyd Rose brass spring claw/screws, Floyd Rose high tension low noise springs, GFS Brass block, Graphtech saddles, full cavity shielding with copper tape, David Allen “Dover” pickups, ‘vintage style’ cloth push back wire, CTS pots, CTS 5way switch. I leveled and polished the top of the brass block and the bottom of the bridge to insure as close to 100% coupling as I could, for maximum resonance transfer. In the process of going with a ‘satin’ look on the hardware, I sanded about 50% of the chrome off the bridge (if you think that provides a tonal difference, Ive never heard it tho)

    The setup: Guitar plugged directly into Avid Eleven Rack, 64 Vibro Champ amp sim, chorus, delay and reverb added. Recorded a direct stereo line out of that into Logic Pro X on a 27″ iMac, 3.1Ghz Intel Core i5, 16G RAM.