Tompkins Industries is in the process of updating all Code 61 and 62 Split Flange Kits from including the Spring Lock Washer (see on left side of Fig. 1) and switching to the SAE approved move to the Hardened Flat Washer (see on right side of Fig. 1)
(Fig. 1)
This change is recommended by the manufacturing specification SAE J518-1, -2,
and -3. The change is due to,
- The revised universal flange clamp design (hole and spotface) to accept both imperial (inch) and metric screws.
- The international acceptance in ISO standards of the metric flat washer with metric screws.
The SAE steering committee harmonized the previous revision to match the ISO standard.
The Split Flange (SF and SFX) and Captive Flange (SFW and SFXW) screw (e.g. bolt) and spotface dimensions have been changed as of 2017 (see Fig. 2).
(Fig. 2 Split Flange and Captive Flange)
SAE has universalized the split flange design to be used with either metric or imperial screws (Type 1 or 2). As a result, flat washers are now standardized as the recommendation for Split Flange (and Captive Flange) clamp assembly. A benefit of the flat washer is the uniform use between either metric or inch screws. The revised screw hole accepts either metric or imperial screws.
The new spotface continues to allow for the old lock washers to be used on the new flange clamp when using only imperial screws. The previous SAE J518 spotface design may not accept the flat washer and for that reason lock washers will remain available with other flange products. Flat washers are metric sized except when using the Code 61 -20 size or Code 62 -16 size. See Table 1 for a complete listing of sizes.
By default, all Split and Captive Flange clamp kits will be offered with imperial UNC screws. If you require metric screws, you must specify your order to ensure all components are metric compatible. As an alternative to the flat washer, lock washer can be supplied upon request at an additional cost and are subject to lead time at the time of order. Please consult customer service (800-255-1008) if you require Split Flange kits with lock washers.
This is a rolling change that started in 2018 with metric thread kits and now include all UNC thread kits. We expect to have all carbon steel split flange kits changed to flat washers within the next few months.