ASME B107.18-2003 pdf free download.PLIERS: WIRE TWISTER
Wire twister pliers shall incorporate a device, which,when actuated, will cause the pliers to rotate about itslongitudinal axis. The halves of the pliers shall be perma-nently joined with a through fastener that shali act asthe pivot or fulcrum point of the pliers. A locking device,when engaged, shali hold the handles in a closed posi-tion in such a manner as to cause the jaws to firmly andsecurely grip and hold strands of lock wire.
A wire clearance opening shall be provided betweenthe two jaws and located between the gripping andcutting areas of the jaws. This opening shall be of a sizeand design which will permit the user to swiftly andeasily deflect double strands of wire out of the sides ofthe jaws and away from the cutting edges when per-forming continuous (multiple)lock wiring operations.The nose design shali be as shown in Figs. 1 through 4and blend with the radius of the sides of the pliers inaccordance with good commercial practice. The maxi-mum permissible opening at the top of the jaws, whenclosed, shall be as shown in Figs.1 and 2.
5.2 Material
The materials used in the manufacture of the pliersshall be such as to produce pliers conforming to therequirements specified herein.
5.3 Finish
Surfaces shall have a rust preventive treatment andbe essentially free from pits, nodules,burrs, cracks,andother conditions that would adversely affect the per-formance or safety of the tool. When provided, coatingsshall be adherent, smooth,continuous,and free fromany conditions that would interfere with their protectivevalue, safety, and function.
5.4 Marking
Pliers shall be marked in a plain and permanent man-ner with the manufacturer’s name or with a trademarkof such known character that the source of manufactureand country of origin shall be readily determined. Mark-ing shall be as permanent as the normal life expectancyof the pliers to whichit is applied (providing the markedsurface has not been subjected to a fretting or abradingaction) and be capable of withstanding the cleaning pro-cedures normally experienced during its intended use.5.5 Handles
Handles shall have a hardness of 36 HRC to 50 HRC,shall be shaped to provide a comfortable handgrip, andshall be free from rough edges and sharp corners.
5.6 Jaws
5.6.1 Hardness. Jaws shall have a hardness of 36 HRCto 50 HRC. The gripping portion of the jaws and wirecutter shall be heat treated to a hardness of 56 HRC to64 HRC. Jaw surfaces and edges shall not damage thewire being twisted.
5.6.2 Cushion Grip Throat. Cushion grip throat, whenprovided,shall grip and retain cut wire end. The cushiongrip throat shall be nonmetallic and capable of with-standing normal use without deteriorating or rubbingoff and shall pass the solvent resistance test in para.6.4.Cushion grip throat shall remain permanently attachedunder normal use.
5.7 Joint Fastener
The fastener shall have a hardness of 25 HRC to 50HRC.
5.8 Spiral Mechanism
The spiral mechanism shall be capable of producinga close, uniform twist in safety wire without binding ofor damage to the mechanism. This mechanism shall bemounted between the handles of the pliers and shall bepermanently affixed to one handle in such a positionthat the longitudinal axis of the mechanism shall corre-spond to the longitudinal axis of the pliers. The mecha-nism, when actuated, shall cause pliers to rotate aboutits longitudinal axis in its intended direction(s). Eachfull actuation of the mechanism shall cause the pliersto make the following minimum number of completerotations:
) for 6 in.(152 mm) size, 21!4 rotations (with auto-matic retum, 2 rotations)
b)for 9 in. (229 mm) size, 3 rotations (with automaticreturn, 21/ rotations)
(c) for 12 in. (305 mm) size,4rotations (with automaticreturn, 31/ rotations) (Type III Reversible, 3 rotations)The design of the mechanism shall permit a comfort-able, adequate grip by the operator.
5.9 Locking Device
The locking device shall be so designed that whenthe pliers’ jaws are closed, the handles must be furthercompressed in order to engage the lock. Release of thelocking device shall be accomplished automaticallywhen the handles are compressed. The locking deviceshall not interfere with the user’s hands when per-forming lock wiring operations.ASME B107.18 pdf download.ASME B107.18-2003 pdf free download
