Inch Cross Recess Pan Head SEMS Screw with Plain and Lock Washers

SEMS screw: plain washer and split lock washer held captive under the head. 2-56 UNC to 1/4-28 UNF, 316 stainless steel.

Section: SEMS screws
Part no.: SG-SEMS-PPPL
Material: Stainless steel
Units: Inch

Overview

A pan head SEMS screw with a cross recess (type Z) and a plain washer and split lock washer held captive under the head. The washer is fitted before the thread is rolled, so it cannot fall off: the screw and washer go in as one part, which saves time on the line and stops loose washers getting lost in equipment.

Made in 316 stainless steel (A4), passivated or chemi-black. Head dimensions to BS 1981 type Z recess, lock washer MS35338. Sizes 2-56 UNC to 1/4-28 UNF.

Specifications

Brand	S&G
Part no. series	SG-SEMS-PPPL
Head	Pan head, cross recess (type Z)
Washers	Plain washer and split lock washer, held captive
Standards	BS 1981 type Z recess, lock washer MS35338
Material	316 stainless steel (A4)
Finish	Passivated or chemi-black
Threads	2-56 UNC, 4-40 UNC, 6-32 UNC, 8-32 UNC, 10-32 UNF, 1/4-28 UNF
Units	Inch (class 2A threads)

Sizes & part numbers

All values in inches. A and B are maximum values; E is the washer stack in the compressed state. Values in inches. D is the plain washer outside diameter, max./min.

Part no.	Thread T	A head Ø (in)	B head ht (in)	C driver no.	D washer Ø (in)	E (in)	F (in)	Standard L1 (in)
SG-SEMS-PPPL-2-56	2-56 UNC	0.167	0.062	No.1	.185/.180	0.04	0.078	.250, .312, .375, .437, .500, .625, .750
SG-SEMS-PPPL-4-40	4-40 UNC	0.219	0.08	No.1	.244/.236	0.045	0.095	.250, .312, .375, .437, .500, .625, .750
SG-SEMS-PPPL-6-32	6-32 UNC	0.27	0.097	No.2	.295/.290	0.051	0.113	.312, .375, .437, .500, .625, .750, 1.000
SG-SEMS-PPPL-8-32	8-32 UNC	0.322	0.115	No.2	.341/.336	0.068	0.139	.312, .375, .437, .500, .625, .750, 1.000
SG-SEMS-PPPL-10-32	10-32 UNF	0.373	0.133	No.2	.391/.386	0.079	0.157	.375, .437, .500, .625, .750, 1.000
SG-SEMS-PPPL-1/4-28	1/4-28 UNF	0.492	0.175	No.3	.562/.557	0.098	0.195	.500, .625, .750, 1.000

How to order

Quote the part number with the underhead length L1, for example SG-SEMS-PPPL-4-40 × .437 in, and the finish: passivated or black. Other lengths are made to order.