Zoro Select
Zoro Select M50302.400.0047 Copper Sealing Washer M40 10 Pack
Copper sealing washers for M40 bolts, 40 mm inner and 47 mm outer diameter, 2 mm thick, pack of 10
- TypeWashers
- Copper construction provides reliable sealing performance
- Annealed heat treatment ensures consistent material properties
- 40 mm inside diameter fits M40 bolt size precisely
- 2 mm thickness with tight tolerance maintains uniform seal
- Pack of 10 washers covers multiple installation needs
M40 Copper Sealing Washers — 10 Pack
These Zoro Select copper sealing washers fit M40 bolts with a 40 mm inside diameter and a 47 mm outside diameter. Each washer is 2 mm thick with a tolerance of +/- 0.2 mm and is annealed for consistent sealing performance. The plain grey copper finish provides corrosion resistance in fluid systems.
Replaces worn or deformed copper washers on M40
Swap them out when the original washer has flattened, cracked or leaked after repeated torque cycles. The jump is worth it when a joint sees frequent pressure changes or temperature swings that work-harden softer annealed copper over time. A fresh 10-pack keeps spares on hand for multi-bolt flanges or scheduled maintenance intervals.
Simple drop-in installation on clean M40 threads
Place the washer flat against the flange face, torque the bolt to the equipment specification and re-check after the first heat cycle. What usually goes wrong is re-using an old washer, over-torquing beyond the 2 mm thickness allowance or mating the copper to a damaged sealing surface that prevents a uniform crush.
Highlights
- Copper construction provides reliable sealing performance
- Annealed heat treatment ensures consistent material properties
- 40 mm inside diameter fits M40 bolt size precisely
- 2 mm thickness with tight tolerance maintains uniform seal
- Pack of 10 washers covers multiple installation needs
Specifications
| Brand | ZORO SELECT |
|---|---|
| Type | Washers |
Questions about this item
What bolt size and inner diameter does the M50302.400.0047 copper sealing washer fit?
The washer fits an M40 bolt and has a 40 mm inside diameter.
How are the annealed copper washers installed and what step is often missed?
Place the plain-finish washer under the bolt head or nut with the 2 mm thickness facing the joint; the step often missed is ensuring the mating surfaces are clean so the soft copper can seal properly.
When should the M40 copper sealing washers be replaced?
Replace them whenever the joint is broken or the 2 mm thick washer shows deformation, as the annealed copper work-hardens and will not reseal a second time.
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