HOW TO INSTALL (SAPL-R)

A.P. LOCK
(Keyless Bushing)

A.P. Lock (Keyless Bushing) is a power transmission component that
enables to clamp shaft and hubs (i.e. pulley, gear etc.) simultaneously
through its surface pressure. S.I.M provides diverse options in regards
to size, body material and surface treatment.

Design of Pressure Flange

In general, SAPL-R series is supposed to be used along with pressure flanges whose design varies according to user’s shaft/hub design. Please refer to the below design variables.

Location of screws (locking bolts) on the pressure flange (F)

Case1: Pressure flange mounted on Hub

F = D + 12 + d_b (screw size)

Case2: Pressure flange mounted on Shaft

F = D – 12 – d_b (screw size)

Thickness of pressure flange (P)

Case1: Fastened with Grade 8.8 class screw

P = 1.3 x d_b (screw size)

Case2: Fastened with Grade 12.9 class screw

P = 1.8 x d_b (screw size)

If more than 2pcs of SAPL-R are mounted simultaneously

Distance(W) between pressure flange and hub/shaft has to be adjusted. Please refer to “Dimensions / Performance” pages for (W) values.

Transmissible Torque Calculation (Formula)

TC = \frac{P_{total} - P_{pre - load}}{0.54} \times 0.12 \times \frac{d}{2000}

$TC = \frac{P_{total} - P_{pre - load}}{0.54} \times 0.12 \times \frac{d}{2000}$

Screw Size (d_b)	Pressure on each screw (P_b [N])
Screw Size (d_b)	Grade 8.8 class	Grade 10.9 class	Grade 12.9 class
M4	3,900	5,450	6,550
M5	6,350	8,950	10,700
M6	9,000	12,600	15,100
M8	16,500	23,200	27,900
M10	26,200	36,900	44,300
M12	38,300	54,000	64,500

If more than 2pcs of SAPL-R are mounted simultaneously, the clamping force on shaft (permissible torque) becomes higher.

SAPL-R/ 1pc mounted :

Tc (Max. Permissible Torque)
SAPL-R/ 2pcs mounted :

Tc (Max. Permissible Torque) x 1.55
SAPL-R/ 3pcs mounted :

Tc (Max. Permissible Torque) x 1.85
SAPL-R/ 4pcs mounted :

Tc (Max. Permissible Torque) x 2.02

A.P. LOCK (Keyless Bushing)