Thread & Hole Dimensions; Mechanical and Performance Requirements Machine Screws SEMS 80-82

Transcription

1 Machine Screws ead Style erence Chart Drive Style erence Chart ead & Drive Dimensions lat lat Undercut orx lat orx lat Undercut lat 5 Combination russ 5 Pan Combination Pan Combination Round 7 Combination ex Washer 7 Round Binding Slotted Binding Undercut 9 russ 9 Oval 7 Oval Undercut 7 ex, Slotted and Unslotted 7 ex Washer, Slotted and Unslotted 7 ex Washer w/ 7 ex Washer with Serrations, Slotted 7 illister 7 orx Pan 7 Pozidriv lat 75 Pozidriv Pan 75 Square lat 7 Square Pan 7 orx lat 77 Round Washer 77 hread & ole Dimensions; Mechanical and Performance Requirements Machine Screws 779 SEMS hread aging Notes orx is a registered trademark of the Camcar Corporation, division of extron Industries. Pozidriv is a registered trademark of the Screw Company. Kanebridge's fasteners with a drive are not manufactured by or connected with the producers of Pozidriv fasteners.

2 Machine Screws ead Styles Schematic ead Style Description pplications/ dvantages Pan Slotted pan heads have a flat or gently rounded top surface, cylindrical sides and a flat bearing surface. and orx pan heads have a rounded top, cylindrical sides and a flat bearing surface. as a general purpose bearing area. Can be substituted in most applications for round, truss or binding heads. Binding as a rounded top surface and slightly tapered sides. he bearing surface is flat with the slotted variety having an annular undercut adjacent to the shank. Preferred design for making a firm electrical connection. lat C countersunk head with a flat top surface and a coneshaped bearing surface with a head angle of approximately. Used in applications where protrusion of the fastener above the mating surface is unacceptable. Use a protrusion gage when measuring head height. \ / M I / I I I I' / lat Undercut Similar to an flat head except that the head is undercut to 7% of its normal side height. Standard for short lengths because it allows greater length of threads. lso avoids transition fillet and assembly interference. NL ^ II M * ^r lat countersunk head with a flat top surface and a coneshaped bearing surface with a head angle of approximately. Preferred over an flat head when fastening in soft materialsthe countersunk head distributes pressure over a larger surface area. illister as a rounded top surface, cylindrical sides, and a flat bearing surface. he greater side height is what distinguishes a fillister head from a pan head. Preferred style for use in counterbored holes. I Indented ex as an indented top surface, six flat sides, and a flat bearing surface. Preferred in high volume assembly where pneumatic equipment is used to drive the screw. Can transmit significantly higher tightening torque levels than other head styles. Indented ex Washer as an indented top surface, six flat sides and a flat washer which projects beyond the sides and provides a flat bearing surface. he washer and hex head are formed together as one piece. Offers greater protection to the mating surface than a standard indented hex head. Increased bearing area reduces likelihood of crushing mating surfaces. russ as a low rounded top surface with a flat bearing surface greater in area than a roundhead screw of the same nominal size. Weaker than pan or round heads but preferred in applications where minimal clearance exists above the head. russ profile provides a trim, finished assembly appearance. Oval countersunk head with a rounded top surface and a coneshaped bearing surface of approximately. Preferred over a flat head in conical applications, or when a more decorative finished look is desired. Countersunk surface nests into mating countersunk application sites. Oval Undercut Similar to an oval head except that the head is undercut to 7% of its normal side height. Standard for short lengths because it allows greater length of threads. Round as a semielliptical top surface and a flat bearing surface. Sometimes preferred over pan head for its smooth surface and appearance.

3 Drive ypes Machine Screws DRIVE YPES OR MCINE SCREWS Schematic Drive ype Uses Most recommended drive type. Provides good control in driving. lways use a driver bit in good condition. Slotted ccepts standard blade screwdrivers. Requires less downward pressure to drive slotted parts than it does those with crossrecessed openings. Use proper fitting blade to minimize slippage. Combination: /Slotted ccepts phillips and standard blade screwdrivers. Often used when fastener is expected to be driven and backedout several times. ex / Slottedex ccepts hex wrench. Slotted drive is added to make it easier to remove the fastener. orx Positiveengaging, fastlocating method of transmitting torque and optimizing worker efficiency. Pozidriv lternative (ype ) Design offers even greater control in driving than drive. Used in automotive and appliance manufacturing. Square Socket Increases productivity with excellent torque transmission and resists camout. Distinctive appearance which discourages tinkering. orx is a registered trademark of the Camcar Corporation, division of extron Industries. Pozidriv is a registered trademark of the Screw Company. Kanebridge's fasteners with a drive are not manufactured by or connected with the producers of Pozidriv fasteners.

4 Machine Screws ead Dimensions lat Edge of head may be rounded or fiat ~ N Slotted L EDS OR MCINE SCREWS SME B^ 5 / 5/ / / ead Dimensions eight Slot Dimensions M R N Dimensions Diam ^ Protrusion bove aging aging

5 iat Undercut ead Dimensions Machine Screws ' l\ V ~ ^ / \ / / * i Edge of head may be rounded or flat R r Slotted UNDERCU L EDS OR MCINE SCREWS ""jj^ L M R N hese Lengths or Shorter are Undercut ead Dimensions eight Slot Dimensions Dimensions Diam. Protrusion bove aging aging / / / / / / / / / / 7/ / / / 9/ / /

6 orx is a renistfireri trademark of the Camnar nmoration. division of extron Industries. Machine Screws ' ead Dimensions orx lat orx lat Undercut ORX DRIVE L EDS OR MCINE SCREWS camcar ead ead eight B auge Penetration allaway orx / / Edge of head may be rounded or flat Protrusion gage ORX DRIVE L UNDERCU EDS OR MCINE SCREWS camcar B R ead ead eight Protrusion bove auging Penetration auging orx /

7 lat Combo russ Machine Screws Slotted 99 Protrusion gage Edge of head may be rounded or flatt * R \ t i M * \~ * r v'» N L ED OR MCINE SCREWS SMEB" ead Dimensions eight Slot Dimensions M R N Dimensions Diam. Protrusion bove aging aging / 5/ t irj \ \ t MhrrN ^Xf/^N ted <sv N L COMBINION DRIVE RUSS EDS OR MCINE SCREWS." ead eight of ead of Slot of Slot M N Dimensions of Penetration aging /

8 Machine Screws ead Dimensions Pan Combo Pan i Slotted PN EDS OR MCINE SCREWS ND SEMS SME B 5 / 5/ / ead Win " eight of ead Slotted ed of Slot of Slot M N Dimensions of N COMBINION DRIVE PN EDS OR MCINE SCREWS./ Screw / 5/ ead Dimensions ead ead eight Slot Dimensions M N Dimensions Penetration

9 Combo Round & ex Washer ead Dimensions Machine Screws irj j N COMBINION ROUND EDS OR MCINE SCREWS SME B ead ead eiqht Slot Slot M N Penetration aging / / / agin^9 Ring " DI r ^<ss y Pt COMBINION EX WSER EDS OR MCINE SCREWS ^ U D P M N Norn cross lats ead eight Washer Washer hickness Slot Slot Protrusion Beyond aging Ring Penetrating aging /

10 Machine Screws ead Dimensions Round Binding Slotted ROUND EDS OR MCINE SCREWS "^ 5 / 5/ / / ead eight of ead of Slot of Slot M Dimensions N of t /"^ \ "P^S \Y/ \ \ PILLIPS BINDIN EDS OR MCINE SCREWS SME.. / ead O otal ead eight ead Oval eight M N

11 Slotted Binding russ * r ~f^^, l ^ UK ead Dimensions r * f t X Machine Screws *a SLOED BINDIN EDS UNDERCU OR MCINE SCREWS SME Bbo O U X ead eight of Oval eight of ead otal eight of Slot of Slot Dimensions of Undercut / Slotted t z: ^~~**. i* i i Mj h r N Z rrjmn RUSS EDS OR MCINE SCREWS SME l^ ead eight of ead of Slot of Slot M N Dimensions of / / / /

12 Machine Screws ead Dimensions Oval OVL EDS OR MCINE SCREWS SME B 5 / 5/ / 7/ / ead O eight of ead Side otal Slot Dimensions M R N Dimensions Diam Protrusion bove aging aging

13 Oval Undercut ead Dimensions Machine Screws Protrusion gage Slotted UNDERCU OVL EDS OR MCINE SCREWS SMEBM 5 / 5/ / 7/ / hese Lengths or Shorter are Undercut / / / / / / / / 5/ / 7/ / 9/ 5/ / O ead Dimensions Side eight otal eight Slot Dimensions M R N Dimensions Diam ' Protrusion bove aging aging Diam

14 Machine Screws ead Dimensions ex & ex Washer Slotted & Unslotted u W i irj^ COS Ud ^ Wf». ~ ~ L* "u f.«' ' " " <s w nr EX EDS ND EX WSER EDS OR MCINE SCREWS SMEB.^ W U cross lats cross Corners eight of ead of Washer hickness of Washer of Slot of Slot / / / /

15 ex Washer & Slotted w/serrations ead Dimensions Machine Screws cross lats PILLIPS EX WSER EDS OR MCINE SCREWS ead eight B Washer U Washer hickness M N Protrusion Beyond aging Ring Penetration aging / Br h«lt 7 L»,i * [^ \\ u k\\ /^I r aging U Ring rdi _^ss < t SLOED EX WSER EDS WI SERRIONS OR MCINE SCREWS cross lats W cross Corners ead eight Washer U Washer hickness Slot Slot P Protrusion Beyond aging Ring /

16 Machine Screws, If t t s~ ^s t ead Dimensions _ * S^" f \f vil * "I N illister & orx Pan Slotted ead \S ILLISER EDS OR MCINE SCREWS o eight of ead of Slot of Slot Side eight otal eight s M N Dimensions of SME B / / / , i ORX< DRIVE PN EDS Camcar D R ead Dimensions Screw ead ead eight / 5/ orx is a registered trademark of the Camcar Corporation, division of extron Industries. Dimensions auge Penetration (allaway) Penetration

17 lat Pozidriv5 Pan ead Dimensions Machine Screws Pozidriv5 W7 POZIDRIV (YPE ) L EDS OR MCINE SCREWS SME.. ead Dimensions eight M R N Dimensions Diam. Penetration aging Protrusion bove aging aging / / / r* / POZIDRIV (YPE ) PN EDS OR MCINE SCREWS SME.. ead eight of ead M N Dimensions of Penetration aging Pozidriv is a registered trademark of the Screw Company. Kanebridge's fasteners with a drive are not manufactured by or connected with the producers of Pozidriv fasteners

18 Machine Screws ead Dimensions I ' r^ pz.. *«M I t or Basic Screw / 5/ SQURE SOCKE L EDS ead ead eight M Square Penetration aging his type of recess has a square center opening, slightly tapered side walls and a conical bottom i&amm M SQURE SOCKE PN EDS SME B! or Basic Screw / 5/ ead ead eight M Square P Penetration aging his type of recess has a square center opening, slightly tapered side walls and a conical bottom

19 orx lat Round Washer ead Dimensions Machine Screws 99' t \ir^/ ~ ORX L ED OR MCINE SCREWS ext ead eight ead M Diam. auge Penetration allaway imum Penetration of Noo auge Sharp bs / / / / 5/ PILLIPS ROUND WSER EDS OR MCINE SCREWS SME.. R Crown Diam ead eight W Washer Washer hickness... D Diam P N Penetrating aging

20 Machine Screws hread Dimensions t Basic major diameter Basic pitch diameter or diameter.xis.of.screw tbnead. EXERNL REDS OR MCINE SCREWS ND SEMS SME B & hreads per Inch Series Designation llowance Major Pitch olerance Stress rea, in ensile Strength,' Ib., min. UN UN / /.5 UN / / / olerance on Length L Screw thru / thru / Up to / in., incl... Over / to in., incl... Screw Length Over to in., incl... Over in. 'ensile strength values are based on, psi. and apply to carbon steel screws and SEMS only. ex and ex Washer head machine screws of sufficient length may be wedge tensile tested. Other head styles may be axial tensile tested..9.9

21 Steel & Stainless Mechanical & Performance Requirements Machine Screws Description straight shank fastener with external threads designed to go through a hole or nut that is pretapped to form a mating thread for the screw. Machine screws form a fastening superior in strength to spaced thread screws. Steel Stainless luminum pplications/ dvantages Steel Zinc is the most common and most popular variety of steel machine screws Steel Zinc yellow screws are popular in electronics applications. Steel Zinc Black and Black Oxide screws are used to blend in with blackcolored components. Stainless steel machine screws are used in applications which require general atmospheric corrosion resistance, in food processing machinery and refrigeration equipment. Stainless is also superior to steel in withstanding some elevation in application operating temperature while maintaining its strength. In some applications, aluminum machine screws can be a less expensive alternative to stainless screws because of their resistance to corrosion and high rate of conductivity. luminum machine screws should be fastened with aluminum nuts to minimize the chance of galvanic corrosion. Material IS or equivalent steel. SE stainless steel alloy ardness Rockwell B7 B. Rockwell B5 B95 (approximate)* ensile Strength, psi. minimum., psi. minimum (, psi after cold working)*, psi. minimum Machine screws which have a nominal diameter smaller than # are not subject to tensile testing. No. and No. 5 machine screws which are shorter than /" are not subject to tensile testing. Machine screws of diameters No. to /" inclusive, which are shorter than either /" or D (where D is the nominal screw size in inches) are not subject to tensile testing. Such machine screws of a size to be tested shall meet the tensile load requirements given on page. Plating See ppendix for information on the plating of steel machine screws Stainless machine screws are usually supplied plain or with a black oxide finish. luminum machine screws are usually supplied without any additional finish. 'ardness and tensile strength standards are offered as guides only for stainless machine screws. here is currently no national standard for these performance requirements for stainless machine screws.

22 SquareCone is a registered trademark of Shakeproof division of Illinois ool Works. Machine Screws Mechanical & Performance Requirements SEMS MCINE SCREWS WI REESPINNIN LOCKWSERS Internal ooth External ooth SplitLock SquareCone Description pplications/ dvantages Ufttnrtnl Material ardness ensile Strength Plating machine screw and freespinning lockwasher manufactured as one assembly. Steel SEMS are available with the following types of washers: internal tooth, external tooth, splitlock and squarecone. Stainless SEMS are offered with external tooth lock washers. he washer/screw assembly makes this a locking screw with the washer providing the locking action. Machine preassembly provides cost savings to the end user. Internal ooth SEMS: Recommended when it it desirable to hide the teeth for appearance or to prevent snagging. External ooth SEMS: Preferred over the internal tooth style as the teeth provide greater torsional resistance being on the larger radius. SplitLock SEMS: Preferred over tooth lockwasher SEMS for use with hardened bearing surfaces. SquareCone SEMS: Provides a higher retained clamp load & improved compensation for thermal cycling and vibration. Can accept a high tension load and maintain spring action. he washer design makes for better control during installation, and improved tool bit life. Ideal for clamping fragile materials and for spanning large clearance holes. Steel Screws IS or equivalent steel. Steel Washers Solitlock: SE 555 carbon steel: oothlock: SE 55: SquareCone : SE 5. Stainless Screws SE stainless steel or martensitic stainless steel Stainless Washers Splitlock: SE 5 5: oothlock: SE stainless steel: SquareCone : stainless steel Steel Screws Rockwell 7 B. Steel Washers Splitlock: Rockwell C : oothlock: Rockwell C 5: SauareCone : Rockwell C. Stainless Washers Solitlock: Rockwell C5 : oothlock: Rockwell C 5: SauareCone : Rockwell B minimum. Steel:, psi. minimum. No. diameter SEMS screws are not subject to tensile testing. No. SEMS screws shorter than /" are not subject to tensile testing. SEMS screws of diameters No. to inclusive, which are shorter than /" or D (where D is the nominal screw size in inches) are not subject to tensile testing. Such SEMS screws of a size to be tested shall meet the tensile load requirements given on page 7. Stainless: No. : 99, psi. minimum; No. & No. : 9, psi. minimum. Note: No., No. and No. SEMS screws which are shorter than /" are not subject to tensile testing. Stainless: No., No. and No. SEMS screws which are shorter than /" are not subject to tensile testing. See ppendix for information on the plating of steel SEMS. OW SEMS SPECIICIONS VRY ROM MCINE SCREWS he maximum diameter of the unthreaded shank shall be less than the maximum major diameter of the thread by an amount sufficient to prevent disassembly of the washer from the screw. he unthreaded length on fully threaded screws is measured to the contacting face of the washer instead of to the bearing face of the screw. he minimum underhead fillet radius is equivalent to 5% of the basic screw diameter.

23 oothlock, Split & Conical SEMS Washer Specs for Pan ead screws Machine Screws O.D. hickness O.D. hickness OOLOCK WSERS OR PN ED SEMS?99 or Basic Screw / Washer hickness Internal ooth Mln Washer Outside Washer hickness External ooth Washer Outside O.D. hickness WSERS OR SPLILOCK & SQURECONE PN ED SEMS SplitLock SME $ S. Square Cone or Basic Screw Washer Inside Washer Section Washer Outside B Washer hickness Washer Outside W hickness +t / * Dimensions of SquareCone washers are to Shakeproof specifications. SquareCone s a registered trademark of Shakeproof division of Illinois ool Works.

24 Machine Screws SEMS Washer Specs for ex Washer ead screws ooth Lock O.D. hickness O.D. hickness OO LOCK WSERS OR EX ED SEMS SME BS or Basic Screw / 5/ / Washer hickness Internal ooth ln Washer Outside Washer hickness External ooth Washer Outside OO LOCK WSERS OR EX WSER ED SEMS SME ^ or Basic Screw / 5/ / Washer hickness Internal ooth Washer Outside Washer hickness External ooth Washer Outside